Surgeon General's Office ?j no./^r C ^ SYSTEM OF MATERIA MEDICA AND PHARMACY: BY J. MURRAY, LECTURER ON CHEMISTRY, AND ON MATERIA MEDICA AND PHARMACY, EDINBURGH. WITH NOTES BY N. CHAPMAN, M. D. PROFESSOB OF MATERIA MEDICA IN THE USIYERSITX OF PENNSTCVANI* IN TWO VOLUMES. VOL. I. PHILADELPHIA: PUBLISHED BY THOMAS DOBSON, AT THE STONE HOUSE, NO. 41, SOUTH SECOND STREET. William Fry, Printer. 1815. District of Pennsylvania, to wit #*»**##» BE IT REMEMBERED, that on the twenty-first * SFAI * ^*y °^ t)ct0°er, in the fortieth year of the independence * ocau. # of thp Un;ted stateg of America, A. D. 1815, Thomas ******** Dobson, of the said district, hath deposited in this office the title of a book the right whereof he claims as proprietor, in the words following, to wit: " A System of Materia Medica and Pharmacy: by J. Murray, lec- turer on Chemistry, and on Materia Medica and Pharmacy, Edinburgh. With Notes by N. Chapman, M. D. Professor of Materia Medica in the University of Pennsylvania. In two volumes." In conformity to the act of the Congress of the United States, in- tituled, " An act for the encouragement of learning, by securing the copies of maps, charts, and books, to the authors and proprietors of such copies, during the times therein mentioned." And also to the act, entitled " An act supplementary to an act, entitled ' An act for the encouragement of learning, by securing the copies of maps, charts, and books, to the authors and proprietors of such copies during the times therein mentioned,' and extending the benefits tliereof to the arts of designing, engraving, and etching historical and other prints." D. CALDWELL, Clerk of the District of Pennsylvania. TO J. MURRAY, M. D. §c. $c. Mv Dear Sir, I HAVE had printed the present edition of your Sys- tem of Materia Medica and Pharmacy, to serve as a Text Book to my Lectures. In making this selection, I am not sensible that I was, in any degree, influenced by the partiality of friendship. As an elementary treatise, the work has confessedly no ordinary pretensions, and it seemed to me to be peculiar- ly well suited to my purpose, as exhibiting within a nar- row compass, a very correct view of the existing state of the science. Nevertheless you will perceive in the notes which are added, that I do not always entirely agree with you. The differences of opinion, however, between us are trivial, and I am sure I need not apologize to you for the critical animadversions which I have occasionally in- dulged. It was originally my intention to have incorporated with the work, many articles, chiefly the indigenous productions of this country, which though imperfectly known to the practitioners of Europe, have fully vindi- cated their titles to a place in the Materia Medica. But, I found the undertaking could not, in this way, be so ad- vantageously executed, and I was also restrained from attempting it, by obvious considerations of delicacy and propriety. I have therefore determined to make these materials the subject of a distinct publication, which I hope will appear at no distant period. This province of science has not altogether been ne- glected. My distinguished predecessor in the chair which I now occupy, has done much towards its im- IV provement, and several of the graduates of our school, h;- :n then inaugural dissertations, signalized their taleii.i by very successfully investigating the properties of a considerable number of our native medicinal vege- tables. Not a little, however, still remains to be accom- plished. I shall, in the work which I contemplate, en- deavour to present a synopsis of all that has been written upon the subject, together with some new mat- ter, the result of my own observations and inquiries. Thus you see, that like yourself, I retain a desire of being useful. But how different is our fate. You already are celebrated throughout the world, as among the most triumphant cultivators of science. I, only known within a very limited sphere as the humblest of its votaries. In looking back on the scenes of my life, there are none to which I recur with greater satisfaction than those of the time which was passed in communion with you, and my other friends at Edinburgh. I have cherished, and shall never cease to cherish for you all the fondest recollections. I am, dear sir, Very truly and respectfully, Yours, &c. N. CHAPMAN. Philadelphia, Nov. 1, 1815. AUTHOR'S PREFACE. THE Elements of Materia Medica and Phar- macy, which I published several years ago, were prin- cipally designed to be subservient to the Course of Lectures I deliver on these branches of Medicine. Having changed the plan of these Lectures for one, which, though not perhaps preferable in itself, I con- sider better adapted to this mode of instruction, the republication of that elementary treatise appeared to me unnecessary, and my other engagements would not allow of my undertaking a work adapted to the new arrangements of my Course. The demand, however, for the former treatise, since the impression of it was exhausted, has been such, as to have convinced me that the plan on which it is exe- cuted is possessed of some advantages, independent of the object I had originally in view. I have been in- duced, therefore, to publish, not indeed a new edition of it, but a more enlarged work on the same plan. Con- sidering it no longer as subservient merely to my Lec- tures, I have endeavoured to render it more complete in itself, so as to form a concise System of Materia Medica and Pharmacy, which, without including the minute details, shall embrace the principles and the more important facts connected with these departments of medical study. Under the classes of the Materia Medica, I have placed those articles only which are employed in mo- dern practice, without taking any notice of the nume- VI PREFACE. rous inert substances which an undue regard to the authority of antiquity has too long retained in publica- tions of this kind. The Pharmacopoeia of the Edinburgh College I have taken as the basis of the pharmaceutical part of the work, having given a translation of its pro- cesses, while I have also introduced whatever prepara- tions of importance are peculiar to the London and Dublin Pharmacopoeias. And I have added those cor- rections in the principles and processes of Pharmacy, which the recent discoveries in Chemistry have ren- dered necessary. To the history of the articles of the Materia Medica, I have annexed, at the end of the first volume, a view of that arrangement in which they are classed, accord- ing to their natural affinities. This, besides affording a contrast with the classification of these substances according to their medicinal powers, will be of some advantage to those attending my Lectures, and enable them to derive more assistance from the present publi- cation as a text book, as it presents an Outline of the arrangement of the Course. CONTENTS Of VOLUME FIRST. Page Introduction, - - - - - - l PART I. General principles of pharmaceutic chemistry, - 3 Sect. I. Of the chemical analysis of the articles of the Materia Medica, - - - - - -3 II. Pharmaceutical Operations, - - 64 PART II. OF MATERIA MEDICA. Chap. I. Preliminary Observations, - - - -81 II. Of the operations and classification of Medicines, 89 III. Narcotics, - - - - - 103 IV. Antispasmodics, - - - - 150 V. Tonics, - - - - - - 160 VI. Astringents, - - - - - 212 VII. Emetics, ------ 236 VIII. Cathartics, ----- 257 IX. Emmenagogues, - - - - -282 X. Diuretics, ----- 288 XI. Diaphoretics, - 306 XII. Expectorants, - - - - - 319 XIII. Sialogogues, ----- 330 XIV. Errhines, ----- 334 XV. Epispastics and Rubefacients, - - - 338 XVI. Refrigerants, - - - 345 XVII. Antacids, ... - . 3^6 XVIII. Lithontriptics, - - - 360 XIX. Escharotics, - - - - 367 XX. Anthelmintics) - - 372 XXI. Demulcents, - - - - - 378 XXII. Diluents, - - 337 XXIII. Emollients, - - - - 388 INTRODUCTION. MEDICAL Science, considered as relating strictly to the treatment of disease, may be presented under two points of view. Under one, the symptoms of diseases are described, their causes are investigated, the indica- tions are delivered by which their cure is to be attempted, and the remedies are enumerated by which these indica- tions are to be fulfilled. When this method is followed, a previous knowledge is supposed of the natural history, properties, and medicinal powers of the substances employed as remedies; and they are no farther subjects of attention, than to point out their applications to particular cases, and sometimes the cautions which, from peculiarity of circumstances, require to be attended to in their administration. But the subject may also be presented under another light. The symptoms of diseases, their causes, and indi- cations of cure, may be supposed to be known, and the remedies themselves become principally the objects of study,—their natural characters, their sensible qualities, their effects on the living system, and their applications to the treatment of morbid affections, forming so many subjects of description or investigation. This constitutes the department of Materia Medica,—understood in the most extensive signification of the term. The medicinal powers of natural bodies are connected with their chemical constitution; they frequently reside not in the entire matter composing them, but in princi- Vol. I. A 2 INTRODUCTION. pies capable of being extracted and obtained in an insu- lated state, and which in this state can often be employed with peculiar advantages. When given in combination too, these substances are liable sometimes to act on each other, and from the changes arising from these mutual actions, to suffer a change in their properties. Hence arises the necessity of a .strict attention to their chemical composition; and a description of their constituent prin- ciples, and of their chemical relations, so far at least as these influence their actions as remedies, belongs to this department of Medicine. Besides this, we are often able by chemical combina- tions, to modify the powers of these substances, to give them more activity, and in many cases, even by the production of new compounds, to obtain remedies which nature does not afford. These are the leading objects of Pharmacy, the principal processes of which are chemical, and which is evidently subordinate to Materia Medica. Regarding all these objects of inquiry as belonging to one department of Medicine, this department naturally falls under three divisions. Under the first may be delivered those principles which are common to Materia Medica and Pharmacy, those which embrace the chemi- cal relations of bodies, and the changes to which they are liable, so far as is connected with their medicinal opera- tions,—forming what may be named Pharmaceutic Che- mistry. Under the second is placed the history of the substances employed as remedies, constituting what is regarded as Materia Medica in the more limited sense frequently attached to the term. And under the third may be considered the processes to which these sub- stances are subjected, with the view of preparing them for administration, forming what is more strictly deno- minated Pharmacy. On these divisions is founded the arrangement of this work. PART I. OF THE GENERAL PRINCIPLES OF PHARMACEUTIC CHEMISTRY. PHARMACEUTIC Chemistry is that branch of chemical science which investigates the composition of bodies, and considers their mutual chemical relations, so far as these are connected with their medicinal pro- perties and applications. It connects the doctrines of Materia Medica and Pharmacy, and forms a proper introduction to the study of each; an exposition of its principles being necessary in delivering the history of the articles of the Materia Medica, and being not less indispensable in explaining the operations of Pharmacy. It includes two subjects, first, the analysis of bodies, so far as relates to the enumeration of their constituent prin- ciples; and, secondly, the general operations to which they are subjected in their preparation as remedies. CHAPTER I. OF THE CHEMICAL ANALYSIS OF THE ARTICLES OF THE MATERIA MEDICA. The ultimate object of chemical investigations, is to discover the composition of bodies; and the result of these investigations is the reducing them into two classes, those which are Simple, and those which are I OF THE GENERAL PRINCIPLES Compound. The former are such as consist of parts perfectly alike; the most minute particles into which a simple body can be resolved, retaining all its essential properties, and being similar to each other. Compound substances can, on the contrary, be resolved into pai ts different in their qualities from each other, and from the compound which they had formed. It is from the union of simple substances that com- pounds are produced. When two simple bodies are placed in contact, under certain circumstances, an attrac- tion is often exerted by the particles of the one to those of the other: they unite and form a compound, having peculiar properties. These compounds are farther capa- ble of combining with other simple bodies, or with each other, which gives rise to a series of bodies still more extensive; and these again are capable of new combina- tions, or of such intimate mixtures with each other, as to form many peculiar substances. There are thus pro- duced, from a few simple substances, all the products of nature, and all those which are the results of the operations of art. It is the province of Chemistry to trace these com- binations; to determine whether bodies are simple or compound, and, if compound, to ascertain the number of their constituent principles, the proportions, and the modes in which they are combined. The general process by which these objects are attain- ed, is termed, in the language of chemistry, Analysis. It is merely the separation of a compound body into its constituent parts, and is effected either by the agency of heat, or by the exertion of a superior attraction. The analysis from the application of heat, differs according to the composition of the body analysed. If a compound, consisting of two simple substances, be ex- posed to heat, it in many cases happens that the mutual attraction by which its principles were united ceases, and a decomposition or separation of these principles takes place. This is an example of pure analysis; no change being produced, but merely the separation of the com- OF PHARMACEUTIC CHEMISTRY. 5 ponent parts of the compound, so that each is obtained in its original state. An analysis more complicated is that where several substances are combined together, in such a manner that their attractions are reciprocally balanced, and one com- pound is formed. When a compound of this kind is exposed to a high temperature, this balance is frequently subverted, and the compound is decomposed. But its constituent principles, instead of passing off pure, enter into«pew combinations with each other, and form other compounds, each of which may be collected, and in its turn analysed It is in this manner that vegetable and animal substances are acted on by heat: the products afforded by their analysis are not such as pre-existed in them, but are compounds formed during the decomposi- tion, from new combinations of their ultimate constituent principles. This is what is named False or Complicated Analysis. Chemical Analysis is also effected by the exertion of a superior attraction. If a compound be placed succes- sively with different substances in situations favourable to the operation of chemical action, one or other of these substances may exert a superior attraction to one or other of ^its component parts; a decomposition will be produced, and from the products the constituent prin- ciples of the compound as well as their proportions may be determined. As compound substances can combine together so as to form a new compound, it is obvious, that this compound may be resolved either into the immediate principles from the union of which it has been formed, or into those of which these consist. It is necessary, therefore, that these should be distinguished. The former are accordingly named the Proximate Principles of a compound; the latter the Ultimate Principles. The proximate principles are of course compounds; the ultimate principles are the elements of these compounds; and the results of analysis are extremely different, according as one or other of these is obtained. 6 OF THE GENERAL PRINCIPLES When by analysis the constituent principles of a body have been obtained, they may often be combined again, so as to reproduce the substance analysed. This opera- tion is named Chemical Synthesis; and when it can be effected, is the surest proof of the accuracy of the analysis. In analysing the various products of nature, we arrive ultimately at substances which we are unable to decom- pose, and which are therefore regarded as simple. The absolute simplicity of these is not indeed established^ for our inability to decompose them may not arise from this, but from the imperfections of our modes of analysis; and it is even probable, that all the substances which are yet known to us may be compounds, and that a more refined chemistry may discover their composition. Until this be accomplished, however, they are regarded as simple, and they are so with regard at least to our knowledge of them. As the ultimate principles, therefore, of all analysis, they are first to be considered in proceeding to the general analysis of the articles of the Materia Medica. Of these bodies, Oxygen is the most important. There is no simple substance which exerts an attraction to so many others, or which gives rise to such important compounds. With a £e\v exceptions, indeed* all the productions of nature are either capable of combining, or are already combined with this principle, and the development of its agencies constitutes the most exten- sive and important part of chemical science. .- Oxygen always exists in the gaseous state: when it enters indeed into combination with other substances, it often becomes concrete; but its properties are at the same time changed, and its descriptive characters are therefore taken from it as it exists in the aerial form. Like other gases it is invisible and elastic; its specific gravity is rather greater than that of atmospheric air; it is absorbed by water, but in a very small proportion. The distinguishing properties of oxygen gas are those of supporting respiration and combustion. An animal lives much longer in this air than it does in any other; OF PHARMACEUTIC CHEMISTRY. 7 and combustion in it is more vivid and durable. It is the only air indeed, which, strictly speaking, can support either of these processes; other aeriform fluids doing so only from the oxygen they contain. Its capacity of supporting combustion is more particu- larly to be assumed as its characteristic chemical pro- perty; combustion being nothing but the combination of oxygen with combustible bodies, accompanied with the emission of heat and light. It also frequently, however, enters into combination without the phenomena of com- bustion being apparent, more especially when the ab- sorption of it takes place slowly, or when it is transferred from a compound in which it exists to another substance. The combination of a body with oxygen is termed Oxygenation, or Oxidation. The products of this com- bination have either certain common properties, belong-'" ing to a class of chemical agents long distinguished by the appellation of Acids; or they are destitute of these properties, and they are then denominated Oxides. Oxygen forms one fourth part of atmospheric air; and it is principally on its agency that the many chemical changes produced in bodies by that air depend. Com- bined with another elastic fluid, hydrogen, in the propor- tion of 85 parts to 15, it forms water, the substance which has the most extensive operation in promoting chemical action by the fluidity it communicates, and which more directly produces many important chemical changes, by affording oxygen to bodies. This element exists as a constituent principle of all acids, and com- municates to them their energy of action. It has more lately been established, that it is also an ingredient in the composition of the alkalis and earths, and that it is there- fore the principle of alkalinity as well as of acidity. With all the metals it combines in different proportions, com- municating to them a greater susceptibility of chemical action, and greater activity in their relation to the living system; and it exists as a constituent part of nearly all the vegetable and animal products. Hence no principle is 8 OF THE GENERAL PRINCIPLES more extensively diffused, and none has a more marked influence in the combinations into which it enters. The elastic fluid which, along with oxygen gas, com- poses atmospheric air, is named Azote or Nitrogen. Its chemical agency is less powerful, nor does it possess any very remarkable property by which it can be charac- terized; hence it is distinguished rather by negative qua- lities. It is lighter than oxygen gas, is incapable of sup- porting combustion or respiration, is scarcely sensibly absorbed by water, and is not combustible in the strict sense of the term; for although it combines with oxy- gen, the combination is not rapid; it does not, after it has commenced, proceed of itself, and it is not attended with any sensible emission of heat or light. Nitrogen gas forms three fourths of atmospheric air, the remaining fourth part being oxygen gas. In more intimate combination with oxygen, and in that propor- tion in which they are mutually saturated, it forms a very powerful acid, the nitric acid; and in lower degrees of oxygenation it forms compound gases which have no acid powers. With hydrogen, and probably a portion of oxygen, it forms ammonia, one of the alkalis; it exists in some vegetable substances, and is a constituent prin- ciple of nearly all the varieties of animal matter. This substance had been usually regarded as simple. The recent researches which have arisen from the applica- tion of galvanic electricity to chemistry, have established some singular facts with regard to it; whence the con- jecture has been formed that it is a compound, and, in particular, that it is connected in chemical constitution with hydrogen: but the subject is still involved in such obscurity as to preclude any certain conclusion. Atmospheric Air, of which oxygen and nitrogen are the essential constituent parts, has merely the aggre- gate properties of these two gases, their combination being so slight that no new powers are acquired from it; and, as the oxygen is the more energetic ingredient, the chemical agencies of this air depend chiefly on the opera- tion of this principle. It yields oxygen to a number of OF PHARMACEUTIC CHEMISTRY. 15 substances, with more or less rapidity, and thus changes their chemical constitution. It sometimes acts too by communicating humidity; and in a few cases, by afford- ing an elastic fluid, carbonic acid gas, which is diffused through it in small proportion. Its nitrogen exerts no active power, but apparently serves merely to dilute, and thus to moderate the action of the oxygen gas. Hydrogen is another elastic fluid, which in the sys- tem of modern chemistry has been regarded as ele- mentary, and the importance of which, as a principle opposed to oxygen in its chemical powers, recent disco- veries appear to establish. In its aerial form, in which form only it can be obtained uncombined, it is the lightest of all the elastic fluids, and the lightest sub- stance therefore whose gravity we can ascertain. It is distinguished farther by its high inflammability; it burns whenever an ignited body is approached to it in contact with atmospheric air, and explodes if previously mixed with the air. The product of its combustion is water, which is therefore considered as a compound of it with oxygen. Combined with nitrogen, it forms ammonia: with the primary inflammables, sulphur, carbon and phosphorus, it forms compound gases: it dissolves even some of the metals, and it is an abundant ingredient in vegetable and animal substances. Water, of which hydrogen is the base, is a sub- stance extremely peculiar in its chemical relations. Its power of combination is extensive, there being few substances on which it does not act, or with which it does not combine; yet in these combinations no ener- getic action is displayed; it in general scarcely produces any alteration of properties; and hence its most import- ant operation is the communicating that state of fluidity to bodies which is in general necessary to their mutual chemical actions. It is more peculiarly the solvent of all saline substances, and of the greater number of the earths; and it dissolves many of the vegetable and animal products. When it communicates oxygen, it produces more important changes. Several of the metals are slowly Vol. I. B 10 OF THE GENERAL PRINCIPLES oxidated by it; and when they are dissolved by acids, it often acts by affording to them that oxygen which is necessary to the solution. Vegetable and animal sub- stances often suffer chemical changes from the oxygen which water imparts, as well as from the fluidity it communicates favouring the re-action of their constitu- ent parts; and in their decomposition at elevated tem- peratures, the elements of the water they contain enter into the composition of the products which these decom- positions afford. There are three substances formerly supposed to be simple, distinguished by the property of inflammability, and hence named Simple Inflammables, which exist as constituent principles of a number of natural products. These are carbon, sulphur, and phosphorus. Recent discoveries appear to favour the conclusion, that the inflammable matter of each of them has not yet been obtained perfectly pure; but that in the state in which they are presented to us, it is combined with a small portion of oxygen, and perhaps of hydrogen; and some analogies even lead to the conjecture, that the ultimate bases are metallic. In this compound state, however, they are destitute of the metallic splendour, opacity, and specific gravity, and are connected chiefly by the com- mon property of inflammability. When united with oxygen, they form acids. Carbon. The ultimate base to which the name of carbon ought to be appropriated is probably still un- known to us; but there are several substances of which it constitutes the greater part, and of course in which it exists in a state more or less pure. Wood charcoal in burning is almost entirely consumed, forming with the oxygen with which it combines a peculiar elastic fluid, carbonic acid, and leaving only a small residuum of earthy, saline, and metallic substances. As a discrimi- nating appellation of the pure inflammable matter which thus combines with oxygen, the term Carbon was intro- duced, and it denoted therefore simply this matter free from the other substances mixed with it in charcoal, OF PHARMACEUTIC CHEMISTRY. 11. and apparently not essential to its constitution. It was afterwards discovered, that the Diamond, which was known to be a combustible body, affords in burning precisely the same product as charcoal, and hence therefore consists of the same inflammable matter. Dif- ferent opinions were advanced with regard to the differ- ence between charcoal and diamond; but from galvanic experiments it appears, that in charcoal the inflammable base is combined with a little hydrogen, in diamond with a very minute proportion of oxygen. In the substance named Plumbago, it is united with a small quantity of iron; it has not therefore been entirely insulated; but it is to this inflammable base common to all these substances, and composing nearly the whole of their weight, that the term carbon is understood to be appro- priated. Carbon, besides existing as an element in the compo- sition of many mineral substances, is an abundant ingre- dient in the products of the vegetable and animal sys- tems. Not being volatile, it forms the principal part of the residual mass when these are decomposed by heat; and it is by this decomposition of vegetable matter, especially of the wood of plants, that it is obtained in the form of charcoal. With oxygen, combined in differ- ent proportions, it forms two elastic fluids, carbonic oxide, and carbonic acid. With hydrogen and oxygen, in different proportions, it forms various inflammable gases. Alkohol, or pure ardent spirit, which is the pro- duct from saccharine matter by fermentation, is a simi- lar compound; and ether, which is formed from alkohol by the action of acids upon it, is of the same composi- tion with a larger proportion of hydrogen. Lastly, this ternary combination of carbon, hydrogen, and oxygen, in various proportions and modes of combination, ap- pears to constitute the principal varieties of vegetable matter. Sulphur is found in nature principally as a consti- tuent part of mineral bodies. It exists combined with many of the metals; and combined with oxygen, form- 12 OF THE GENERAL PRINCIPLES ing sulphuric acid, it enters into the composition of a number of saline and earthy compounds. It is highly inflammable; in burning it combines with oxygen, prin- cipally in that proportion which forms an elastic fluid, highly pungent and suffocating, sulphurous acid. With a large proportion of oxygen, it forms a dense inodorous liquid acid, sulphuric acid. With hydrogen, it forms an inflammable gas, sulphuretted hydrogen, which exists in nature impregnating water in the sulphurous mineral waters; and this compound, either alone, or with an additional proportion of hydrogen, forming what is named super-sulphuretted hydrogen, enters into combi- nation with alkalis, earths and metallic oxides, forming several important pharmaceutic preparations. Lastly, sulphur exists as a constituent part of animal substances: hence sulphuretted hydrogen is generally evolved in the decomposition of these by heat or putrefaction: it has also been detected in the composition of a few vege- tables. This inflammable substance appears, from gal- vanic experiments, to consist of a peculiar base, not yet obtained insulated, combined with small proportions of hydrogen and oxygen; and it is probably this base which enters into the preceding combinations. Phosphorus, like sulphur, is found chiefly as an in- gredient of animal matter. Combined with oxygen, in the state of an acid, it also exists in several of the natural compounds of the mineral kingdom. It is of a soft con- sistence like wax, semi-transparent, and of a white *br yellowish colour; it is so highly inflammable that it burns spontaneously when exposed to the air. It com- bines with two proportions of oxygen, forming two acids, the phosphorous and the phosphoric. With hy- drogen it forms a gas highly inflammable; and it unites with sulphur and with the metals. It too contains minute quantities of oxygen and hydrogen, and its sim- ple base is therefore unknown. The c,lass of Metals is an extensive one, the sub- stances to which this name is appropriated being nume- rous, and the number being still farther augmented, if OF PHARMACEUTIC CHEMISTRY. IS the lately discovered bases of the alkalis and earths are to be regarded as metallic. The physical properties, characteristic of the metals, are opacity, great lustre, density, and tenacity under the two modifications of ductility and malleability. These are possessed in dif- ferent degrees by the different metals, and if the bases of the alkalis and earths are to be admitted as metals, the property of density cannot be considered as distinctive, as some of these are even lighter than water. With regard to chemical properties, the metals are fusible, in general not volatile except at very intense heats; they are capable of combining with oxygen, with hydrogen, sulphur, carbon, and phosphorus, with each other, and when oxidated are capable of uniting with acids, alkalis, and earths. Of these combinations, that with oxygen is the most important; and in relation to the object of this outline, the only one requiring any farther observations. This combination is effected in various modes. When heated in contact with the air, they attract its oxygen: if the temperature be very highly elevated, as in that produced in the galvanic circuit, they display during this oxidation the phenomena of combustion; even if the temperature is less elevated, several of them burn more or less rapidly; but the greater number are oxidated more slowly, and without any sensible extrication of light. Several metals are slowly oxidated by water, or by the joint action of air and water at natural temperatures. And all of them can be oxidated by acids, the acid either directly imparting oxygen to the metal, or enabling it to attract this principle from the water which is present. The compounds of metals with oxygen belong iii general to the order of oxides. They are destitute of the physical properties of the metals, and have an earthy like appearance. Two or three metals acquire, in their highest state of oxygenation, acid powers. In combining with oxygen, different metals unite with very different quantities of it. Eath of them com- bines too with different proportions of oxygen, giving rise to the production, from the same metal, of oxides 14 OF THE GENERAL PRINCIPLES having very different properties. These proportions have been supposed to be determinate, but there is every reason to believe that they are not so, except from the operation of external circumstances connected with the oxidation; that the natural tendency of the law regulating these combinations, is to unite the metal with the oxy- gen, in quantities indefinite, from the minimum to the maximum, and that uniform and determinate propor- tions are established in particular cases, only by causes foreign to the reciprocal attraction whence the combina- tion results,—a circumstance of much importance, as is to be afterwards pointed out, with regard to the pharmaceutical processes on the metals. When the metals are combined with oxygen, they become capable of combining with the acids, and they then acquire greater activity and power of chemical action. This previous oxidation of a metal is always necessary to its combination with an acid, and hence, when acids act on metals, they first impart to them oxygen, or enable them to attract oxygen from the water, or sometimes from the air, and then combine with the oxide that is formed. As the same metal is capable of existing in different states of oxidation, so by combining in these states with the same acid it forms very different compounds; and these compounds are farther diversified by the different proportions of acid combined in them. Metals are rendered active on the living system, prin- cipally by being thus combined with oxygen, or farther combined with acids. In their metallic state, they seldom produce any sensible effect; and any effect they do pro- duce appears to arise from their being chemically acted on by the gastric fluids. When oxidated, they become much more active; and still more so when the oxide is combined with an acid. And even the degree of oxy- genation considerably influences their powers; so that from the same metal preparations of very different de- grees of medicinal activity may be obtained, though all agreeing in the kind of action they exert. OF PHARMACEUTIC CHEMISTRY. 15 It would be foreign to the object of this sketch to give the description of the individual metals: it is sufficient to have stated with regard to them these general facts. Few of them exist as common ingredients in the compo- sition of natural substances, with the exception of iron. A class of substances, possessing certain common properties, the ultimate principles of the various com- pounds, not metallic or inflammable, which occur in the mineral kingdom, had been distinguished by the appel- lation of Earths. An analogy had often been observed to exist between these substances and metallic oxides; and the conjecture had even been advanced, that they are of similar constitution, or consist of metallic bases combined with oxygen. By a train of investigation, originating in very different analogies, the composition of the earths has been established, and their bases disco- vered to be substances previously unknown, and pos- sessing general properties, so nearly allied to those of metals, as to be sufficient perhaps to justify the placing them in that class; yet still so far different as to afford some reason for regarding them at least as a peculiar order. The Primary or Simple Earths, as they are named, to distinguish them from the various earthy aggregates which exist in nature, have been described as substances insipid, insoluble in water, fixed, and nearly infusible by heat, uninflammable, and capable of combining with acids, so as to neutralize the acid properties. All these characters are not equally appropriate; for there are several of the earths which have a pungent taste, and are soluble in water to a considerable extent, and all of them may be fused by very intense heats. The principal earths are Silex, Argil, Magnesia, Lime, Barytes, and Strontites; Zircon, Glucine and Ittria, having more doubtful claims to be ranked in this class, or existing in such minute quantities as to be comparatively unimportant. Silex is an abundant ingredient, not only in mineral substances, but is frequently contained in vegetable pro- 16 OF THE GENERAL PRINCIPLES ducts, and forms part of the earthy residuum of their decomposition. It is tasteless, nearly infusible and inso- luble in water, and is peculiarly distinguished by its inertness, and comparatively limited range of combina- tion; among the acids it combines only with the fluoric, and even scarcely neutralizes its properties. It unites with the fixed alkalis, and by fusion with the other earths and the metallic oxides. Argil is insipid, soft to the touch, infusible, insolu- ble in water, and particularly distinguished by forming with that fluid a ductile plastic mass, which hardens and contracts considerably when heated. With the acids it forms compounds, which have generally a sweetish styptic taste, and which possess, to a certain extent, the property of astringency. Magnesia exists in the form of a very light white powder, smooth and impalpable; infusible, insoluble in water, and not forming with it a coherent paste; it has a slightly bitter taste, changes the more delicate vegetable blue colours to a green, and combines with acids, form- ing compounds, in general very soluble, and having a bitter taste. In its pure form it is medicinally employed as an antacid, and its saline compounds have in general a cathartic power. Lime, or Calcareous Earth, displays still greater energy of action. It is so far soluble in water, as to com- municate to the solution a very harsh styptic taste, and the power of changing the vegetable colours to a green. Being usually obtained by the decomposition of lime- stone, chalk, or marble, by heat, it is in the form of a hard mass; but when it imbibes water, either directly or from exposure to the atmosphere, it splits, and falls down into a white powder perfectly dry. It is infusible. Combined with the acids, it neutralizes their properties. Its action is considerable on the animal system. Directly applied to animal matter, it acts chemically, producing decomposition, and thus operating as an escharotic. Given in solution, it exerts an astringent and tonic power, which power is also displayed in several of its OF PHARMACEUTIC CHEMISTRY. 17 saline combinations; and by its chemical agency it acts as an antacid, and, as has been supposed, likewise as a lithontriptic. Its base has been obtained, though not perhaps perfectly insulated; it has the metallic lustre, and appears to be highly inflammable. Barytes surpasses lime in energy of chemical action. Like it, when in a solid mass, it absorbs water rapidly, and falls into a dry white powder; its taste is harsh and caustic: when water is combined with it, it fuses by a heat comparatively moderate; but when this is dissipated, the heat requires to be raised to a much higher point. It is more soluble in water than any of the earths, cold wa- ter dissolving a twenty-fifth of its weight, and boiling water even more than half its weight; this latter solu- tion depositing as it cools, transparent prismatic crystals. Its solution changes the vegetable colours to a green. This earth combines with the acids, and appears to exert to them very powerful attractions, as it decomposes their compounds with the other earths and the alkalis,—a cir- cumstance probably owing, however, rather to the inso- lubility of the compounds it forms, than to any superior force of attraction. It exerts affinities to the other earths, and combines also with sulphur and phosphorus. Of all the earths, it is the one which acts most powerfully on the living system. Even in small quantities, it occasions unpleasant symptoms, and its preparations prove poison- ous to animals. From this quality, and from another, the great specific gravity of several of its saline combi- nations, particularly the native sulphate and carbonate, barytes was often more peculiarly supposed to be of a metallic nature. Its decomposition has been effected by the application of galvanism, and a base obtained from it, of a metallic appearance, having the colour of silver, con- siderably heavier than water, fusible at a heat below red- ness, not volatile, inflammable, and reproducing barytes when combined with oxygen. Strontites, the last of these earths, bears a close re- semblance to barytes in many of its properties. Like it, it has a pungent acrid taste, is soluble in water, crystal- Vol.I. C 18 OF THE GENERAL PRINCIPLES lizable from its saturated solution by cooling, changes the vegetable colours to a green, combines with the acids, and decomposes a number of the compounds which they form with the other alkalis and earths. Its native compounds too have a considerable specific gra- vity. It is, however, much less soluble in water than barytes; it requires nearly 200 parts of cold water to dissolve it, though boiling water dissolves it in much larger quantity. Barytes decomposes its salts. It is not poisonous, nor does it appear to exert any marked ac- tion on the living system. A characteristic property of it is that of its salts causing inflammable bodies to burn with a blood red flame. Following the series from the metallic oxides through the earths, we arrive at the Alk a l is. These possess the chemical property common to the whole, and most cha- racteristic, that of combining with acids, neutralizing the acid properties, and forming compounds, analogous in general properties to those formed by the earths and me- tallic oxides with the acids. But they display still more energy in their chemical actions than the earths, and are more remote in their qualities, from the oxides of the common metals. Their taste is extremely harsh and acrid; they are highly caustic; abundantly soluble in water; exerting indeed such an attraction to it as to im- bibe it from the atmosphere, or attract it from other bodies: they are fusible by a moderate heat, and by a stronger heat are volatilized; they change the vegetable blue and purple colours to a green, the yellow to a brown, and they combine with oils, rendering them dif- fusible or soluble in water. These properties belong to two of the alkalis which are naturally concrete, potash and soda. A third, ammonia, exists when uncombined as a permanent gas, but it is instantly condensed by wa- ter, and absorbed by it in large quantity, and the general properties of it not connected with its peculiar form are the same. One of the most splendid discoveries of Modern Che- mistry is that of the composition of the Alkalis. Am- OF PHARMACEUTIC CHEMISTRY. 19 monia had been known to be formed from the combina- tion of hydrogen with nitrogen, and analogy suggested to chemists the conclusion, that the two fixed alkalis are of similar constitution, containing either of these ele- ments as a common principle; and thus led them aside from the analogy suggested by their connection with the metallic oxides in neutralizing the acid properties, from which it might have been inferred, that they and the earths are compounds of metals with oxygen. Mr. Davy, availing himself of the powerful instrument of chemical analysis which galvanism affords, submitted potash and soda to its action, and succeeded in effecting their decomposition. Their bases are substances ex- tremely peculiar; they have the metallic lustre, opacity and tenacity, but not the property formerly considered as characteristic of metals, that of great specific gravity, as they are even lighter than water; they are very fusible and volatile, and pass through these changes of form, as well as different states of cohesion, in a very limited range of temperature; they are also highly inflammable; combined with oxygen, they form these alkalis; and if these bases are to be admitted as metallic, the analogy in chemical constitution is established between the al- kalis, earths, and metallic oxides. Potash, or as it ought to be named, (in conformity to the rule of giving a similar termination to the names of substances belonging to the same order,) Pot ass a, is obtained from the incineration of vegetables, especi- ally from the wood; the saline matter remaining after the wood has been burnt, consists principally of this alkali, in combination with carbonic acid, being freed from the impurities by lixiviation; this acid is abstracted by the action of lime, the alkali is obtained in solution, and, by evaporation, can be obtained in a solid state. It is of a white colour, crystallizable, fusible, and vola- tile at a higher heat; abundantly soluble in water, soluble also in alkohol, powerfully caustic, and possessed of all the alkaline properties in a high degree. There is some uncertainty, whether it exist in fie vegetable matter 20 OF THE GENERAL PRINCIPLES from which it is procured in the state in which it is pbtained, or whether its base is a constituent principle of that matter, and is oxygenated during the combustion: one reason for admitting the latter opinion, at least in part, is, that the alkali cannot be extracted in so large a quantity by any other process as by burning. Potassium, as the base of potash has been named, is at the temperature of j2° a solid substance, hard and brittle, of a white colour, opake, and with the lustre of polished silver; at 50° it becomes soft and malleable; at 60° it is in the form of small globules, somewhat con- sistent; at 70° it becomes more mobile and liquid; and at 100, it is completely so. It requires a temperature near to a red heat to volatilize it. It is lighter than water, or even than alkohol or ether. It is highly inflammable, when heated to its vaporific point, burning with intense heat and vivid light; at lower temperatures it combines more slowly with oxygen; it passes through various stages of oxidation to the maximum, when it forms the alkali, being then combined with oxygen in the pro- portion of 85 to 15. Such is the strength of its affinity to this principle, that it takes it rapidly from water, and from all the acids. It combines with the primary in- flammables, and with the metals. boDA, or Mineral Alkali as it has been denominated, in contradistinction to the other alkali, which has been distinguished by the epithet of vegetable, exists as a constituent principle of several saline mineral substan- ces, but it is usually extracted from the combustion of marine plants. It is afforded by the combustion, com- bined with carbonic acid, and associated with various other saline substances, and is obtained pure by the same general process as that applied to potash. Whether it pre-exist in sea plants, or whether these, in common with land vegetables, afford potash in burning, which decomposes the muriate of soda with which they are impregnated from their situation, so as to afford soda, has not been well determined. In its physical proper- ties this alkali bears a considerable resemblance to the OF PHARMACEUTIC CHEMISTRY. 21 other. It is solid and white, crystallizable, though with difficulty, from its watery solution; extremely acrid and caustic, fusible and volatile from heat, having a strong attraction to water, changing the vegetable colours to a green, and possessing all the alkaline pro- perties. From potash it is principally distinguished by the very different compounds it forms. Sodium, the base of soda, is white and opake, and has the lustre and appearance of silver; is soft and mal- leable; is somewhat lighter than water; it is less fusible than potassium, not losing its cohesion at a lower tem- perature than 120°, and requiring for its perfect fusion a heat of 180; it is also less volatile. When heated to ignition, it burns vividly; at lower temperatures it ab- sorbs oxygen without undergoing combustion; it ab- stracts oxygen from water, and from the acids, frequently with inflammation. It appears to be susceptible of va- rious degrees of oxidation; at the maximum when the proportion of oxygen is about 21 to 79, it forms soda. It acts on the inflammables and the metals nearly as potassium does. Ammonia. This alkali has usually been denominated volatile, from its volatility compared with the others, even when it is combined with water, being considera- ble. In its insulated state it exists as a permanently elastic fluid; its odour is extremely pungent; water ab- sorbs it in very large quantity, and this solution forms what is named Liquid Ammonia. Its volatility, or ten- dency to assume the elastic form, and its comparative dilution, lessen the energy of its action; and hence, though possessed of the general alkaline properties, it appears weaker than the others in the affinities it exerts. Its composition was supposed to have been established, nitrogen and hydrogen appearing, both from analytic and synthetic experiments, to be its constituent princi- ples. When the composition of the fixed alkalis was discovered, and they were proved to be oxides, analogy evidently suggested the conjecture, that oxygen would probably also exist in ammonia; and Mr. Davy, from 22 OF THE GENERAL PRINCIPLES some experiments, concluded, that this is the case, though these have not been fully confirmed by subse- quent experiments. The analogy in the chemical con- stitution of ammonia to that of the fixed alkalis, has however been established by the important discovery, that it affords metallic matter; Berzelius and Pontin, Swedish chemists, having found, that when the alkali is placed at the negative wire in the galvanic circuit in contact with quicksilver, the quicksilver increases in bulk, becomes thick, and at length a soft solid,— changes perfectly similar to what are produced in it by the addition of metallic matter, and which can scarcely be conceived to arise from any other cause. The matter producing these effects in the experiment, must have been derived from decomposition of the ammonia; and it is accordingly found, that when this substance re- ceives oxygen, either from the air or from water, am- monia is reproduced. Either hydrogen or nitrogen must therefore be of a metallic nature, combined pro- bably with a portion of oxygen; and it is not improbable that both these gases may be modifications of the same base. The analogy in constitution has thus been ren- dered complete, with regard to the three alkalis, and they, as well as the earths, are connected by a series with the oxides of what are more strictly denominated metals,—one of the most perfect examples of generali- zation which the science of chemistry affords. The last important class of chemical agents is that of Acids. The characteristic acid properties are a sour taste, the power of changing the blue, purple, and green colours of vegetables to a red, and that of combining with the alkalis, earths, and metallic oxides, forming compounds, in which, when the combination is esta- blished in the due proportion, the properties of the acid, and of the base with which it is united, are equally neutralized. The more powerful acids have a conside- rable degree of causticity; they have a strong attraction to water, and they act with energy on inflammable and metallic substances. OF PHARMACEUTIC CHEMISTRY. 23 All the acids are compounds of oxygen, and this ele- ment is therefore regarded as the principle of acidity. This truth was established by Lavoisier, with regard to a number of the acids, and extended by analogy to a few which had not been decomposed. It has been con- firmed, with regard to these, by more recent investiga- tions. The bases of the acids are either inflammable or metallic. The production of acidity is usually the result of their full oxygenation, and in some cases the base combines with two proportions of oxygen, forming two acids, different in their properties from each other. On these facts, with regard to the chemical constitu- tion of the acids, their nomenclature is founded. The base being specific with regard to each acid, while the oxygen is common to them, it is from the name of the former that the name of the acid is derived; and, by a variation in the termination of this name, the different acids which may be formed from the base, by a differ- ence in the degree of oxygenation, are distinguished; the name terminating in the syllable ic, when the acid is that which contains the larger proportion of oxygen, and in the syllable ous when it contains the smaller pro- portion. Thus sulphur forms two acids, by combining with two proportions of oxygen; the term sulphur is the radical whence the names of these are derived, and ac- cording to the above principle, the one is denominated the sulphuric, the other the sulphurous acid. Where a large quantity of oxygen can be farther combined with an acid without increasing, but rather diminishing its acid powers, the name is expressed by prefixing the epithet oxy, as oxymuriatic acid. Acids have an extensive power of combination. From the numerous affinities they exert, and from the facility with which they afford oxygen, they are the most active of any of the compound chemical agents, and are hence employed in many pharmaceutic operations. Those of most importance under this view are the sulphuric, nitric, a»d muriatic. The Sulphuric Acid, formed from the full oxy- 24 OF THE GENERAL PRINCIPLES genation of sulphur, exists combined with a small quantity of water in the form of a liquid of great den- sity, and from this state of concentration acts power- fully; exerting strong attractions to other bodies, and though, from the strength of affinity between its princi- ples, it does not directly afford oxygen with facility to many substances, it enables them to attract oxygen from water, and thus subjects them to chemical change. The Sulphurous Acid, which is formed from the same base in a lower degree of oxygenation, existing naturally in the elastic form, which is an obstacle to its entering into combination, and not being very largely absorbed by water, so as to form a concentrated solu- tion, is much weaker. Nitric Acid is the result of the full oxygenation of nitrogen; and the oxygen, not being retained in the combination by a strong attraction, the acid yields it readily, and hence acts with more facility and energy on inflammable and metallic substance than any other acid,—oxidating the former, and first oxidating, then combining with the latter; hence in pharmacy it is used as the most general solvent of the metals. What is named Nitrous Acid, is the nitric, with an impreg- nation of nitric oxide gas; it is of a yellow colour, and emits similar coloured dense fumes, while the other is colourless; the chemical agencies of both are nearly the same. Muriatic Acid exists when uncombined in the aerial form, but it is absorbed in large quantity by water, and forms a liquid acid of considerable strength. Its analysis had not been effected, and even yet, by the action of potassium on it, there have been established only some singular facts, with regard to water combined with it, and the effect of this water on its acidity; the quantity of water in combination with the acid even in its elastic state, is supposed to amount to at least one- third of its weight; and though the acid itself cannot be obtained free from this water, yet when combinations of it with other acids are procured in this state, the acid OF PHARMACEUTIC CHEMISTRY. 25 powers are completely suspended, and are restored on the addition of a little water. This acid, not directly affording oxygen to bodies, oxidates them only by ena- bling them to attract oxygen from the water it contains; it thus dissolves metals; and it farther combines with other substances, as the alkalis or earths. It is capable of uniting with an additional proportion of oxygen, forming what is named Oxymuriatic Acid, which, al- though its acid powers are weaker, imparts oxygen more readily to bodies. And, with a still larger proportion of oxygen, it forms a third acid, Hyper-oxymuriatic Acid, which gives to the saline compounds in which it exists, the power of acting with much energy on inflammable bodies, in consequence of the very large quantity of oxygen condensed in the combination, and not retained by any great force. Other acids, less important as pharmaceutic agents, are the Carbonic, Phosphoric, Boracic, and Fluoric. Carbonic Acid, the product of the complete oxy- genation of carbon, existing in the elastic form, and being absorbed by water only in sparing quantity, has no very active chemical power, but is of importance from existing in many natural combinations, particu- larly of saline and earthy substances belonging to the Materia Medica. The characters eminently distinguish- ing it are its only weakening, not entirely neutralizing the properties of the alkalis, when in combination with them, and its being disengaged rapidly with efferve- scence by other acids from these compounds, and from those it forms with the earths. Phosphoric Acid has phosphorus for its base; and the affinity between this base and the oxygen, with which it is combined, being strong, it scarcely acts on bodies by oxygenating them, but simply by entering into combination with them; nor are these combina- tions comparatively of much importance. Phosphorous Acid, in which the proportion of oxygen is smaller, is still less important. Vol. I. D 26 OF THE GENERAL PRINCIPLES Boracic Acid exists in the concrete form, and its chemical action is comparatively weak. So powerful is the affinity between its base ancl oxygen, that it has only been decomposed by galvanism, or by potassium; and its decomposition, there is reason to conclude, is even not complete: a dark olive coloured substance is obtain- ed, inflammable, and which, by combining with oxygen, reproduces boracic acid; this substance being probably the real base in a lower degree of oxygenation. Fluoric Acid is elastic, and is not very largely ab- sorbed by water; its chemical action is from these cir- cumstances, therefore, not powerful. It unites, however, easily with the alkalis and earths, and, what peculiarly distinguishes it, is capable of dissolving siliceous earth. It suffers partial decomposition from the action of potas- sium, oxygen being abstracted from it, and a chocolate coloured substance deposited which burns in oxygen, and reproduces the acid. There is a series of acids with compound bases, de- rived from the vegetable and animal system; but those of them entitled to notice will be best considered with the classes of substances with which they are more strictly connected. The acids combine with the alkalis, the earths, and the metallic oxides; and when the combination is esta- blished in the due proportion, the chemical properties of the acid, and of the base with which it is united, are mutually neutralized. Hence these compounds are named Neutral Salts, and, as an order of chemical agents, they are distinguished by certain common pro- perties. They can always be obtained in the solid state: they are generally, though not universally soluble in water; those of them which are soluble, are capable of assuming a crystalline form, the form being very diffe- rent in different salts. Those which crystallize from their aqueous solution, always retain a quantity of water greater or less in combination, essential to the crystal, and therefore named their water of crystallization. When heated, the increase of temperature is often sufficient to OF PHARMACEUTIC CHEMISTRY. 27 enable this water to dissolve the real saline matter: this is named the watery fusion of salts; as it evaporates, the salt becomes concrete, and, by a farther increase of heat, is either fused or decomposed. The term Neutral Salt is sometimes restricted to those of which the al- kalis are the bases: those formed from the earths are named Earthy Salts; and those from the metallic oxides, Metallic Salts. The nomenclature of the whole series is in the modern chemical language simple, and, at the same time, systematic and precise. They are formed into genera and species, according to the acids, and the bases of which they are composed; the name of the genus is derived from that of the acid, the name of the species from that of the base with which the acid is united. Thus all the salts formed from sulphuric acid are con- sidered as constituting one genus, and are named Sul- phates; and the name of each species is expressed, by adding the name of the base, as Sulphate of Soda, Sul- phate of Lime, Sulphate of Iron, &c. The acid which sulphur forms in a different degree of oxygenation, the Sulphurous, forms a different order of salts; these are named Sulphites; and in like manner we have Nitrates and Nitrites; Phosphates and Phosphites, &c. Those formed from oxymuriatic acid are named Oxy-muriates. Salts are sometimes formed with an excess of acid, or with an excess of base: the acid being considered as the principle forming the genus, these are distinguished by prefixing to the usual name the epithet super, when the acid is predominant, and the epithet sub when it is defi- cient, or when the base is in excess, as Super-sulphate of Potash, Sub-carbonate of Soda, &c. When an acid is combined in one compound with two bases, as some- times happens, the names of both bases enter into the name of the Salt, as Tartrate of Potash and Soda. Thus, by this simple system, a facility of nomenclature is afforded; the whole is uniform and systematic, and the memory is aided, by the name pointing out the nature of the salt; and the adoption of this nomenclature in Pharmacy is an important improvement. 28 OF THE GENERAL PRINCIPLES So far the chemical analysis of unorganized sub- stances connected with the Materia Medica has been the subject of consideration. It remains to take notice of the analysis of those belonging to the vegetable and ani- mal kingdoms,—a subject of much importance, par- ticularly as it relates to the vegetable part of the Materia Medica, and which from this importance, as well as from the nature of the substances themselves, requires to be considered with more minute details^ < These two classes of bodies are distinguished by very obvious chemical characters. In unorganized sub- stances, the principles are few, and are combined gene- rally in very simple states of union; their analysis can be executed with accuracy; even the proportions of their principles can be determined with precision, and they can be again combined so as to form the decom- posed substance, thus confirming the analysis by syn- thesis. But, with regard to the products of organization, while the composition so far as it relates to the ultimate elements, is more uniform, it is with regard to the modes in which they are united much more complicated. They consist of a few common principles; but these, presented to each other in the vessels of the organic being, have been placed under circumstances indefinitely varied, and which art can very imperfectly imitate. Combina- tions of the same elements are formed, therefore, greatly diversified, and properties are derived from differences of proportions, or modes of union extremely minute. Hence their accurate analysis is executed with diffi- culty,—a difficulty increased by the circumstance, that these elements having strong mutual affinities, cannot in general be obtained insulated, but when the com- pound has been decomposed enter into new combi- nations liable to be modified by slight variations of cir- cumstances; the proportions therefore can seldom be determined with accuracy, the modes of union in gene- ral remain unknown, and the confirmation by synthesis is entirely precluded. OF PHARMACEUTIC CHEMISTRY. 29 Another character distinguishes these two classes. The composition of unorganized bodies being more simple, is not so liable to be subverted; their consti- tuent principles being few, their affinities operate with more force, and the combination is more permanent. That of organized bodies being more complicated, has characters precisely the reverse. Composed always of several elements, the affinities are more nicely adjusted, and are therefore more easily modified; and their prin- ciples having tendencies to enter into numerous forms of combination, slight variations of circumstances sub- vert the equilibrium. Hence the susceptibility of de- composition by which they are distinguished: they are liable even to spontaneous changes from the reaction of their elements, and when this is favoured by humidity, elevation of temperature, or the action of the air, new combinations are established, whence the original com- pounds are decomposed* From the peculiar constitution of the products of or- ganization, there are two kinds of analysis to which they are subject. The object of the one is to discover their ultimate composition; that of the other is less refined, being confined to the investigation of the proximate principles of which they are composed. It is seldom that a vegetable substance is homoge- neous. The seed, for example, the bark, or the leaves of a plant, is not of one uniform composition, but con- sists of various proximate principles in a state of mix- ture, or of slight combination, and capable of being easily separated from each other. Now these are often connected with their medicinal virtues; the virtue resid- ing perhaps not in die entire substance of the leaf, bark, or seed, but in a principle capable of being separated, and which may frequently be employed in its insulated state. Hence the importance of the analysis of the vege- table substances belonging to the Materia Medica, so far as relates to their proximate principles; the knowledge it conveys enabling us to employ them with more dis- crimination, and to submit them to the proper phar- 30 OF THE GENERAL PRINCIPLES inaceutic treatment. An enumeration of their proxi- mate principles, and more particularly of those on which their medicinal powers depend, accordingly always enters into their description as articles of the Materia Medica. This analysis is executed in various modes, adapted to particular cases, according to the principles which form the vegetable substance. An important principle is sometimes separated merely by heat. The temperature cannot indeed be elevated very high, as then the proximate principles of the vege- table would be themselves decomposed, and their ele- ments brought into new combinations. But at a heat comparatively moderate, as that of boiling water, this does not happen; and at this temperature several of the principles of plants, such as their essential oil, cam- phors, and some others not very well defined, are volati- lized without decomposition and of course can be ob- tained pure. The action of different solvents is of more extensive use in conducting the vegetable analysis. Water dis- solves several of their component principles, such as gum and extractive matter, tannin, saline substances, and some others. These are dissolved in greater or less quantity, and in more or less purity, according to the temperature of the water employed. In general, by raising the water to its boiling point, it is able to dis- solve them more completely; but some of them are apt to be volatilized, and others altered in their composition, especially if the atmospheric air is not excluded. Of the substances which the water holds dissolved, part are separated as it cools; the gum can be precipitated by alkohol; the saline substances may be crystallized, or can be discovered by evaporating the solution to dryness, and exposing the mass to such a heat as will destroy the inflammable parts; and tannin is detected by its chemical tests. Alkohol is another agent of much importance in executing the vegetable analysis. It dissolves the resin, OF PHARMACEUTIC CHEMISTRY. 31 balsam, camphor, and essential oil: these solutions are decomposed by water, each substance being separated, and discernible by its peculiar qualities. Equal parts of alkohol and water, or proof spirit as it is named, is also often employed as a solvent in the analysis of vege- tables. Ether dissolves nearly the same principles as alkohol. And the acids, alkalis, and soluble earths, are sometimes of utility as re-agents, in pointing out the existence of peculiar principles. Lastly, in the analysis of vegetables, we are often able to procure several of their proximate principles, by me- chanical means, particularly by expression. Sometimes, too, they exude spontaneously from the growing vege- table, or are obtained by it from incisions made in the branches or trunk. After we have discovered the proximate principles of vegetables, the next step is to ascertain their composi- tion. This is an investigation attended, however, with much difficulty as being liable to all the deceptions aris- ing from a complicated analysis, and incapable of being confirmed by the surer test which synthesis affords. The composition of these substances with respect to their ultimate principles is nearly uniform. All of them contain carbon and hydrogen, generally if not invariably united with oxygen: some farther contain nitrogen and phosphorus; and in others several of the metals, particu- larly iron and manganese, exists. Lime, too, and the two fixed alkalis, either pure or more commonly in combi- nation with some of the acids, are not unfrequently con- stituents of vegetable matter. These latter substances, however, are seldom in any considerable proportion; nor in general do they appear to modify much the pro- perties of the substances in which they exist. Nitrogen, and perhaps lime when present, appear to have the most important influence, and with the exception of the few compounds of which they form a principal part, it may be said, that the vegetable proximate principles consist of carbon, hydrogen and oxygen; the differences in their properties being produced by differences in the 32 OF THE GENERAL PRINCIPLES proportions of these principles, and of the modes in which they are combined. That a difference in the proportions of these ele- ments may give rise to the differences in the properties of the compounds which they form, cannot be doubted; since in many other cases of chemical combinations, where there is no difficulty in the analysis, differences equally important and well marked are produced by this cause. In vegetable substances we accordingly can often trace this as the cause without being able to point out any other. Thus fixed and volatile oils have proper- ties in many respects dissimilar: by analysis both are found to consist of carbon and hydrogen, united only in different proportions, the volatile oils having more hydro- gen in proportion to the carbon than the fixed have: this is a cause sufficient to account for the difference in their properties; and it accords sufficiently with that difference, for hydrogen being a substance extremely rare and volatile, those compounds in which it pre- dominates, as ether, alkohol and others, are in general light and volatile. The greater volatility, therefore, of the essential, compared with the fixed oils, may be ascribed to its predominance. In other cases, it is probable that the mode in which the constituent principles of these substances are united, is the cause of the difference in their qualities. This is indeed a cause which can be but imperfectly inves- tigated, either by analysis or synthesis; but it is con- ceivable a priori, and sufficiently confirmed by che- mical facts, that a difference in the mode of union may give rise to very important diversities of properties. If a compound, for example, consist of three elements, these may be united in two modes. Their attractions may be reciprocally balanced, and they may form what is named, in strict propriety, a ternary combination; or, from a variation in the circumstances under which the union has been effected, two of them may be combined, and the compound thus formed may exert an attraction to the third principle, unite with it, and form a new sub- OF PHARMACEUTIC CHEMISTRY. 33 stance. The compounds resulting from these different modes of combination, though composed of the same principles, united perhaps even in the same proportions, would still have properties different from each other. Still greater diversities will be produced where the ele- ments are more numerous, and the possible modes of union of course more diversified. And when we con- sider these causes from difference of proportions, and modes of combination, we shall scarcely be surprised at the number of different substances, immense as it is, which nature forms from a few elementary principles. The proximate principles of vegetables are some- times analysed by exposure to heat: their elements enter into new combinations, and from the nature of the pro- ducts, we discover what the principles were. Thus, if the substance exposed to heat yields a large quantity of acid, we conclude that it contains a considerable quantity of oxygen as a constituent part. If it afford much em- pyreumatic oil, we infer that it contains a large propor- tion of hydrogen, this principle being necessary to the constitution of that product. When ammonia or prussic acid is afforded by this kind of analysis, we conclude, for the same reason, that nitrogen has been a constituent principle. And by the same mode are discovered the earths and metals which had been present in it; these remaining after the volatile parts had been expelled. Lastly, by the quantity of charcoal which remains as a residuum, we can form some conclusion as to the quan- tity of carbon which the vegetable substance contained. Their analysis is also effected by exposing them to heat with the access of atmospheric air, and collecting the products of the combustion that takes place. From the nature of these products, we can ascertain the pro- portions in which they were united. Oil, for example, when subjected to this analysis, yields nothing but car- bonic acid and water. We conclude therefore that it is composed of carbon and hydrogen, since these princi- ples, united with oxygen, form these products, and since, if any other simple substance had existed in the Vol. I. E 34 OF THE GENERAL PRINCIPLES oil, it would have appeared either pure or in combina- tion with oxygen. We can even determine in this man- ner the proportion in which the carbon and hydrogen existed in the combination. From knowing what quan- tity of carbon exists in a given quantity of carbonic acid, and what quantity of hydrogen exists in a given quantity of water, we thus also discover whether any oxygen had existed in the composition of the oil. They are sometimes analysed by subjecting them to spontaneous decomposition. It is thus that sugar is brought into the state of fermentation; and from the products of the fermentation the principles of the sac- charine matter are determined. Lastly, their analysis is sometimes executed by the agency of the nitric acid, which communicates to them oxygen, and by the product ascertains the nature of their acidifiable base. Such are the methods by which these principles of vegetable matter are analysed. It is to be remarked, that the analysis is so difficult, as to afford, even when executed with the greatest care, only approximations, and as applied to the articles of the Materia Medica is seldom of utility, since we can scarcely ever discover any relation between the ultimate composition and the medicinal powers of the substance analysed. These, in common with all its properties, no doubt depend on that composition; but our modes of analysis are still too limited and imperfect to admit of our tracing the con- nection between them. The application of chemistry, therefore, to the vegetable substances belonging to the Materia Medica, is, as has already been remarked, in a great measure confined to the discrimination of their proximate principles. The proximate principles of vegetables are numerous, and of very different kinds. They are not all to be met with in every vegetable, or in every period of vegeta- tion: some exist only in certain plants, and that only in their state of vigour and maturity: at other times they are to be found only before they have arrived at that OF PHARMACEUTIC CHEMISTRY. 35 period; some are deposited in particular organs, others are diffused through the whole substance of the vegeta- ble, and mixed in a manner more or less intimate with all its parts: and some are nearly peculiar to certain ve- getables, while others are common to almost every plant. Those only require to be pointed out in this sketch, which are particularly connected with medicinal properties. These principles are the products of vegetation from a common juice or sap, which circulates freely through every part of the vegetable system, being supplied by absorption from the soil, and perhaps from the atmo- sphere. It varies in its qualities, particularly according to the season, and the progress of the plant to maturity; frequently too it has an intermixture of the proper juices: it always contains the usual elements of vegeta- ble matter, with generally saline substances, having prin- cipally lime for their base. By the chemical changes it suffers from the action of the vessels of the plant, aided by the action of the air and of light, its elements pass into various states of combinations, whence the peculiar products of vegetation are formed. The first transition of the sap appears to be into Mu- cilage, or Gum, one of the proximate principles con- tained in greatest abundance in vegetables. It is found in all young plants, in greater or less quantity; and is often so abundant in the plant, as to be discharged by spontaneous exudation. It abounds also in their roots, stalks, and leaves, and especially in their seeds. It is an inodorous, insipid, and glutinous substance, soluble in water, in every proportion, and forming with it a thick viscid solution, which by evaporation affords a tena- cious mass, that when dried is brittle and again soluble. It is insoluble in alkohol, "ether, or oil, and is precipi- tated from its solution in water by the addition of alko- hol. It does not absorb oxygen from the atmosphere; though its solution becomes sensibly acid by keeping, owing to partial spontaneous decomposition, and the combination of part of the principles of the gum, so as 36 OF THE GENERAL PRINCIPLES to form acetic acid. Exposed to heat it is neither fusi- ble nor volatile. At a temperature superior to 212, but inferior to that of ignition, it is decomposed; its princi- ples entering into new combinations: the products are an acid liquor consisting principally of acetic acid, car- bonic acid and carburetted hydrogen gases, with a little ammonia, and a residuum of charcoal containing lime, one ounce of gum affording 6 grains of lime. This lime is also detected by adding sulphuric acid to a solution of gum. From these products of the analysis, it is evi- dent that the ultimate principles of gum are, oxygen, h)drogen, and carbon, with smaller proportions of ni- trogen and lime. Gum is not capable of passing into the vinous fermentation, which appears to be owing to the portion of lime existing in it, as lime has the effect of preventing even sugar from suffering this change. Gum is not inflammable; for although, when heated, in contact with atmospheric air, it combines with oxy- gen, it emits no flame. The principal products of this combination are carbonic acid and water. By the action of nitric acid it is converted into oxalic, malic, and sac- cholactic acids. Oxymuriatic acid converts it into citric acid. Gum is usually obtained either by spontaneous exu- dation, or by incisions made in the trunks and branches of trees. It is more or less pure as it is obtained from different plants. Its existence in vegetables is detected by boiling gently the vegetable substance with water: the water dissolves the gum, and if much of that prin- ciple be present, the solution is glutinous. It may be allowed to remain till the impurities have subsided; then be evaporated to the consistence of thin syrup; and the addition of 3 parts of alkohol will separate the whole of the gum in flakes. Pure gum is not an active substance, considered with respect to its effects on the living system. In medicine it is only used for its lubricating quality; and so little activity does it exert, that it has often been taken for a considerable time as an article of food. From its che- OF PHARMACEUTIC CHEMISTRY. 37 mical properties it is of rather more importance. As a component part of vegetable matter, it renders the other parts more soluble in watery liquors, and may thus favour their action on the stomach. In Pharmacy it is used as a medium to combine balsams, resins and oils with water. If a small quantity of any of these sub-, stances be triturated with a little gum or mucilage, on the addition of water they remain suspended in it, form- ing a white milky like mixture, retaining all the pro- perties of the balsam or oil. Though pure gum is thus inactive, yet the virtues of many vegetables depend on a gummy matter. Fecula is a principle approaching in several of its characters to gum. Like it, it is soluble in hot water, and forms a viscid glutinous solution; but it is at once distinguished by being perfectly insoluble in cold water. It exists principally in the tuberose roots and grami- neous seeds. It is extracted by beating the dried root or seed with a large quantity of water; the liquid soon becomes milky, from the diffusion of a white powder through it. On being poured from the remaining vege- table matter, and allowed to remain at rest, this powder is deposited, and when washed and dried is the fecula of the plant. It is generally mild and insipid, of a white colour, with a peculiar kind of brilliancy, soft to the touch; but portions of the other principles of the plant sometimes adhere to it, from which it receives colour, smell, and taste. Starch is the fecula of wheat, and is the most abundant part of that grain. Fecula is insoluble in alkohol. The action of the acids on it is somewhat analogous to that they exert on gum, dissolving it when they are weak or diluted, but decomposing it when they are more concentrated. The alkalis also dissolve it. Exposed to heat, it is charred, and suffers decomposition, affording products which in- dicate carbon, hydrogen and oxygen to be its consti- tuent principles. A property eminently characteristic of it, and probably depending on its composition, is that of being convertible into saccharine matter, and thence 38 OF THE GENERAL PRINCIPLES ultimately passing into the vinous fermentation,—a property not belonging to gum or any other principle. This conversion takes place in germination, and is accompanied with an absorption of oxygen, and forma- tion of carbonic acid. Fecula is a substance highly nutritive, and is usually contained in those plants which serve as food. It is sometimes employed in its pure state in medicine, on account of its nutritive quality, and from its being easy of digestion: sago and salop are substances of this kind. Gluten. This principle is usually associated with fecula, and is obtained in the process in which the fecula is separated. It then appears as a viscous, elastic, and fibrous like substance, which from its close resem- blance to the animal product named Gluten, has been denominated Vegetable Gluten. It is obtained from the flour of wheat in greatest abundance: the flour is made into a paste with water, which being compressed by the hand, while a stream of water falls upon it, the fecula is carried off in the state of powder: the mucila- ginous and saccharine parts of the grain are dissolved by the water; and there remains a tenacious ductile mass, forming the gluten: it has scarcely any taste, is of a grayish colour, and when dried is semi-transparent, resembling glue in its appearance: it is insoluble in water, and is dissolved in very small quantity by alko- hol: by the action of nitrous acid, it is converted into oxalic acid, giving out, at the same time, nitrogen gas: decomposed by heat, it affords a large quantity of am- monia, and it is subject like animal matter to putre- faction. It contains a larger proportion of nitrogen than any other vegetable product does, and it is supposed to render those vegetables in which it is present highly nutritive. Another principle occasionally found in vegetables, but belonging more exclusively to animal substances, is that which has been named Albumen, from its resem- blance to the animal principle of that name. It is solu- ble in cold water, its solution being coagulated by heat: OF PHARMACEUTIC CHEMISTRY. 39 it is coagulated also by alkohol, but it is dissolved by the alkalis: like gluten it is liable to putrefaction, and furnishes a large quantity of ammonia by distillation. This principle is found in hemlock, scurvy grass, cresses, and several other plants, and is obtained from the fresh expressed juice of the leaves when they are heated nearly to the boiling point; the albuminous mat- ter coagulating, and separating in the form of flakes. A similar separation takes place on the addition of spirit of wine. It is contained also in the seeds of other plants, particularly in the different nutritive grains; in the farina of wheat, for instance, it is found dissolved in the water which is employed in separating the fecula from the gluten. This principle, it may be added, has been re- garded, and perhaps justly, as a variety of gluten; it differs little from it in chemical properties; and the pe- culiar physical qualities supposed to be distinctive of gluten are obviously derived from the process by which it is obtained. Saccharine Matter. This exists in many vege- table substances, especially in their fruits and roots, but often intimately united with their mucilaginous and extractive matter. When freed from these, its taste is sweet, without any peculiar flavour; it is soluble in water and in alkohol; is capable of crystallizing; its watery solution enters first into the vinous, and then into the acetous fermentation. By the action of nitric acid, it is converted into oxalic acid; by decomposition by heat, it affords a large quantity of empyreumatic acetic acid, a small quantity of empyreumatic oil, carbonic acid and carburetted hydrogen gases, the residuum being char- goal. It consists, therefore, of carbon, hydrogen and oxygen; and from the large quantity of acid which its analysis yields, it appears to contain more oxygen than any other vegetable substance that is not acid. Sugar appears to be formed from the fecula of the vegetable in which it exists. It contains nearly the same principles as it does, and the operation of malting throws considerable-light on its formation; in this process, the 40 OF THE GENERAL PRINCIPLES fecula of grain is converted into saccharine matter, oxy- gen is absorbed, and carbonic acid formed; and this abstraction of carbon, if it constitutes the whole change, of course proves that the sugar, which is the product of the operation, has an increased proportion of hydrogen and oxygen. Saccharine matter has little activity, though there are some varieties of it, in which some weak medicinal powers reside. Oil is a common proximate principle of vegetable matter; it is of two kinds, expressed or fat oil, and dis- tilled, volatile, or essential oil. These have the common qualities of unctuosity and inflammability; but they also possess peculiar properties, by which they are distin- guished as distinct species. The expressed, fat, or fixed oils, are thick and unctu- ous, insipid and inodorous; they congeal on exposure to cold, are lighter than water, and insoluble in that liquid; they are likewise insoluble, except in very minute quan- tity, in alkohol, and they combine with the alkalis, form- ing soap. They are not volatilized at the temperature of 212: some require to be raised to 600 to make them boil, and the condensed oil is changed in its properties. At a temperature somewhat higher, they are decomposed in close vessels, and burn when the atmospheric air is not excluded. They also slowly absorb oxygen at a low temperature; a small quantity of an acid is formed, which renders them rancid; by longer exposure to the air, they are inspissated, and evtn become at length concrete. Those oils in particular which have been expressed with the aid of heat, and which are named drying oils, suffer this last change, and are ultimately converted into a resinous matter. Expressed oils consist chiefly of carbon and hydrogen, as is established by the products of their decomposition by heat, which are chiefly carburetted hydrogen and carbonic acid. The products of their combustion are water and carbonic acid. These oils are generally contained in the seeds and fruit of vegetables, and only at the period of their matu- OF PHARMACEUTIC CHEMISTRY. 41 rity. They are extracted by expression, or by decoction with water; they are frequently impregnated with part of the extractive, mucilaginous or resinous particles, which the seed or fruit contains; from which they de- rive colour, and in many cases peculiar taste and odour, and even perhaps certain medicinal powers. In general, however, they have little activity as medicines. They are mild and emollient, and are used principally for these virtues. They are rendered miscible with water by the medium of gum or sugar, or by the addition of a small quantity of any of the alkalis. Volatile or essential oils have characteristic properties different from those of the expressed oils. They are vola- tile at a low temperature, and are entirely and quickly converted into vapour at the heat of boiling water, with- out being decomposed; they are soluble in a small proportion in water, and hence the impregnation which water receives from many vegetables by distillation. In alkohol, they are completely soluble; but they do not combine with the alkalis with facility; they are in gene- ral odoriferous, pungent, and even acrid; they are more highly inflammable than the fixed oils, and by exposure to the atmosphere they slowly absorb oxygen, are thick- ened and coloured more deeply, lose much of their smell and pungency, and are at length converted into sub- stances of a resinous nature. This change is partly owing to the escape of part of the oil, but principally to the oxygen absorbed combining with part of their hydrogen. These oils, from their analysis by heat, or by com- bination, appear to consist principally of carbon and hydrogen. They differ from the fixed oils in containing a larger proportion of hydrogen; hence they are more volatile, and more inflammable, and during their com- bustion they afford a larger quantity of aqueous vapour. Volatile oils are less abundant in the products of vege- tation than some other principles; they do not exist indeed in any considerable quantity but in the aromatic plants: in some plants, the oil is confined to the flowers, fruit, leaves, or bark; sometimes it is contained in several Vol.1. F 42 OF THE GENERAL PRINCIPLES of these parts, and in a few instances it is found diffused through every part of the plant. The quantity varies not only according to the age, but also according to the vigour of the plant; hence it is much influenced by cli- mate, soil, and season. It is remarkable, that some of the most odoriferous flowers, as the rose or jessamine, yield scarcely any essential oil, though they lose their flavour by a gentle heat. Some of these oils, being contained in distinct vesi- cles, may be obtained by simple pressure. In this manner, essential oils can be obtained from orange or lemon rind. More usually, they are procured by distilla- tion; the vegetable is boiled in water; the essential oil is volatilized with the aqueous vapour; both are condensed in close vessels; the water has the taste and flavour of the plant, from having dissolved a small part of the oil: $ the greater part of it, however, is collected pure, either swimming on the surface of the water, when the oil is lighter, as is generally the case, or, in a few cases, when it is heavier, having fallen to the bottom. The essential oils of vegetables may be considered as medicines of some activity. They have always the odour, and generally the taste of the vegetable from which they are obtained, accompanied with more or less pungency. Some of them, however, are less pun- gent and less acrid than the vegetable matter from which they are procured, these qualities residing in the resin, or some of the other proximate principles. A proximate principle, found in some vegetables, similar in many of its properties to essential oil, is Camphor. It is a solid substance of a white colour, semi-transparent, having a strong peculiar smell, and a penetrating taste; tenacious, and slightly unctuous to the touch. It is very sparingly soluble in water, but is completely soluble in alkohol, ether, and oils; from these solutions, it is precipitated by the addition of water. It evaporates entirely, though slowly, at the common temperature of the atmosphere; at a higher temperature, in close vessels, it is sublimed without OF PHARMACEUTIC CHEMISTRY. 43 alteration; it is also highly inflammable, the product of the combustion being carbonic acid, and a quantity of what is named camphoric acid. It is acted on by the more powerful acids, sulphuric acid charring it and forming a portion of tannin; nitric acid dissolving it, and decomposing a portion of it, converting it into an acid; muriatic, fluoric, acetic and carbonic acid dissolving it, without materially changing its composition, as the greater part can be precipitated by water. Nitric acid, repeatedly distilled from it, converts it into a concrete acid, named camphoric acid, which appears to be dif- ferent from any known acid. By particular management, camphor may be decom- posed by heat. If it is intimately mixed, with six parts of clay, and made into small balls, by the addition of water, its volatilization is prevented, and, by the heat which may be applied to it, its decomposition is effected. A volatile oil, fragrant and pungent, of a golden yellow colour, amounting to one third of the weight of the cam- phor, distils over; a quantity of charcoal, about one fourth of the weight of the camphor, remains; the re- maining products of the decomposition are, carburetted hydrogen, carbonic acid gas, and camphoric acid. From the result of this analysis, camphor appears to differ from the essential oils, principally in containing a much larger proportion of carbon, since, by its decomposition by heat, it is resolved principally into charcoal, or com- pounds of carbon, and into an oil, which has all the properties of an essential oil, being odorous and pun- gent, volatile and inflammable, soluble in alkohol, and precipitated from it by the addition of water. Camphor is found in distinct vesicles, in the wood and bark of certain vegetables. It is also contained in many essential oils, as those of lavender, sage and others, from which it is deposited on long keeping. The curious fact has been established, that it may be artificially formed, this formation of it taking place in the action of muriatic acid on oil of turpentine. The same relation which camphor bears to the vola- 44 OF THE GENERAL PRINCIPLES tile, wax seems to have to the fixed oils. This substance, though formed perhaps by the bee, is also a product of vegetation; it is yielded by the leaves and fruit, and it is sometimes intimately mixed with the resin, gum, or extractive matter of plants. It is insoluble in water, and is soluble in very small quantity with the aid of heat in alkohol. It combines with the fixed alkalis, though with some difficulty. It unites easily with the expressed oils. It melts at a moderate heat. By distillation in close vessels it affords an acid, and a considerable quantity of thick oil, a small quantity of charcoal being the resi- duum. Resin. This principle is in some measure connected with essential oil, and in plants is often united with it, as well as with other principles. Some vegetables, however, exude juices which concrete into a matter entirely resi- nous, and it is from these that the characters of the sub- stances belonging to this genus are taken. The distin- guishing properties of a resin are its existing in a solid state, being insoluble in water, but soluble in alkohol, ether, and oils; the solution in ether or alkohol is de- composed by water: resins are in general odorous and sapid, though neither of these qualities is essential to a pure resin; they are inflammable, and burn with much smoke; at a temperature nearly that of boiling water they melt; but they cannot be volatilized without being decomposed. In close vessels the products of their de- composition by heat are water, empyreumatic acetic acid, an empyreumatic oil, and a residuum of charcoal, indicating carbon, hydrogen, and oxygen, to be their ultimate principles. At the common temperature of the atmosphere, they do not combine with oxygen; neither are they acted on by water; the solutions of them in alkohol are therefore employed under the form of var- nishes, to preserve other bodies from alteration by exposure to the air. They are dissolved by the fixed alkalis, likewise by some of the acids, especially the acetic: the stronger acids decompose them. The existence of resin in a vegetable is discovered by OF PHARMACEUTIC CHEMISTRY. infusing it in alkohol; this dissolves the resin if any is present, and it can then be precipitated from the solution by the addition of water. The method of estimating the quantity of resin in any vegetable, is by ascertaining the increase of weight which alkohol acquires from it by digestion, or the alkohol may be evaporated by a mode- rate heat, and the resin obtained pure. Resins are in general more active than gums, with respect to their medicinal powers. The purest resins are indeed nearly inert, but there are many vegetable substances which act powerfully on the system, that appear to consist principally of resinous matter, and it is in this resinous part that their powers reside. The proper solvent or menstruum of resin is alkohol; by this it can be extracted from some of the other constituent parts of vegetables, though there are others which are soluble in the same fluid, and therefore it is difficult to obtain the resin pure. Though resin is insoluble by itself in water, yet part of it can be taken up, and kept suspended by the medium of gum. These two prin- ciples are often naturally mixed in vegetables, forming what are named Gum-resins, and some of the most active articles of the Materia Medica are natural compo- sitions of this kind. Their properties are derived from the two principles of which they consist: thus, they are only partially soluble either in water or in alkohol; they are soluble in alkaline liquors; they are not fusible by' heat, they only soften, and if the heat is raised higher are decomposed, affording a little ammonia with the usual products, probably derived from the gum they contain. The proportions of gum and resin, thus mixed, are in different substances of this family very various; but they are generally such, that a mixture of equal parts of water and alkohol dissolves the gum-resin. This is their proper solvent; it also dissolves some other vegetable principles, particularly extract, and hence it is the menstruum most generally used in Pharmacy to extract the active matter of vegetables. 46 OF THE GENERAL PRINCIPLES Balsams are resinous juices, with an intermixture generally of essential oil, and containing always a por- tion of the acid named Benzoic Acid. They are usually thick and tenacious, becoming by age concrete. They are odorous and pungent, principally from the essential oil they contain. A principle of considerable importance in its pharma- ceutic relations, is what has been named by the French Chemists, by whom its characters were first established, Extr ac t, or Extractive Matter, and which is supposed to constitute the active matter of many vegetables. Its leading character is that it is soluble equally in pure water and in alkohol; and hence a solution of it in the one fluid is not precipitated by the addition of another. By this property it is distinguished both from gum and resin, the one being insoluble in water, the other in alkohol. The compound of the two, or gum-resin, is indeed partly soluble in either of these fluids, but it never is completely so, since if it contain as much gum as renders it soluble in water, it is only partially dis- solved by alkohol; and if it consist principally of resin, so as to be completely dissolved by alkohol, it is imper- fectly dissolved by water. If a gum-resin be digested with alkohol, the tincture it affords is decomposed by water, and, vice versa, its watery solution is decomposed by alkohol. There is another character by which extractive matter is distinguished, that of suffering decomposition when exposed in a humid state to the atmospheric air; this takes place even at natural temperatures, and with still more rapidity when the temperature is raised, as when the extractive matter is boiled in water: it then becomes insoluble and comparatively inert. This change, Four- croy ascribed to the fixation of oxygen. According to T. Saussure, oxygen is indeed absorbed, but carbonic acid is at the same time formed; he supposes, too, that part of the oxygen and hydrogen of the extractive mat- ter combine and form water, and that the inert insoluble precipitate has therefore an increased proportion of OF PHARMACEUTIC CHEMISTRY. 47 carbon. It is from this cause apparently that the medi- cinal powers of many vegetables are injured by decoc- tion in water with the admission of air, and not, as was at one time believed, from the dissipation of any volatile active principles; many plants indeed which sustain in- jury from this operation, containing no such principles. By oxymuriatic acid, extract is converted into a con- crete substance of a yellow colour, insoluble in water, probably from a similar change. It exerts affinities to argil and to metallic oxides. By heat it is decomposed, affording empyreumatic oil and acid, with a portion of ammonia; and in this, as well as in its spontaneous de- composition, when the re-action of its elements is fa- voured by humidity, it leaves as a residuum carbonates of potash and lime. This principle is supposed to be the base of what are named the Extracts of Plants;—preparations formed by boiling vegetables in water, and evaporating the clear liquor to a thick consistence. As procured in this way, it must generally have an intermixture, greater or less, of those principles, which are soluble in water; and from being so liable to decomposition, it must be injured du- ring the evaporation. It is the basis, too, though in a similar state of intermixture and partial decomposition, of what are named the inspissated juices of plants. It exists also in the seeds, leaves, bark and wood. Though the characters of this principle appear to be distinctive, there is still some ambiguity with regard to it, particularly from the circumstance, that these cha- racters are not uniform; a principle existing in some vegetables which has some of these distinctive proper- ties without the others; as, for example, in Peruvian bark, the active matter of which is rendered inert and insoluble by decoction in water, and so far has one of the peculiar properties of extract; while it has not the other, that of equal solubility in alkohol and water, but is more soluble in the former than in the latter. Nor is there any certainty that this extractive matter has been obtained pure and insulated; and it is therefore pos- 48 OF THE GENERAL PRINCIPLES sible that it may consist of some of the other principles in a state of mixture, their properties being modified by their reciprocal action. Tannin. The important medicinal property of as- tringency, appeared from some chemical facts to be dependent in vegetable substances on a peculiar prin- ciple, as it is discoverable in them by a chemical test, that of striking a deep purple colour with the salts of iron. This effect is exhibited by all the powerful vege- table astringents, and in a degree nearly proportional to their astringency. A peculiar acid having been dis- covered to exist in these astringents, afterwards named Gallic Acid, it was supposed'to be the principle on which this property depends. But subsequent experi- ments have proved, that it resides in a principle of a different nature, which being the agent chiefly concerned in the operation of tanning, has received the name of Tan or Tannin. This principle exists in all the powerful vegetable astringents; it is extracted by maceration with water, and is detected in the infusion by a peculiar test, that of the animal principle denominated Gelatin. If a solu- tion of gelatin is added to the infusion, it becomes turbid, and a precipitate is thrown down composed of the tannin and gelatin in combination. We have no very perfect process for obtaining tannin in an insu- lated state; but the most simple is precipitating it from the infusion of a vegetable astringent by lime water, and afterwards submitting the compound of lime and tannin, which is formed, to the action of dilute muriatic acid, which abstracts the lime, and leaves the tannin. Tannin evaporated from its solution is loose and fria- ble, having a resinous fracture, of a brown colour, a peculiar odour, and a taste rough and bitter. It is solu- ble in water, either cold or warm, and in alkohol not very highly rectified. It appears to suffer decomposition from exposure to the air in a humid state. By the acids, it is precipitated from its watery solution, and by some of them is decomposed. It unites with the alkalis, form- OF PHARMACEUTIC CHEMISTRY- 49 ing soluble compounds; with, the earths it forms com* pounds of sparing solubility; it exerts affinities to the metallic oxides, and it is principally from its action that infusions of vegetable astringents produce dark coloured precipitates with metallic salts. Exposed to heat, it affords an acid liquid, an oil, and a considerable quantity of carbonic acid, leaving a spongy charcoal. Its action on animal gelatin is its most important pro- perty in relation to the object of the present outline, as on this probably depends its astringent power; it com- bines with it, forming an insoluble precipitate, whence it corrugates and renders more dense the animal fibre of which gelatin constitutes a principal part. It exists in all the powerful vegetable astringents, mixed with ex- tractive matter, mucilage, gallic acid, and other princi- ples. It has also been established, that it is capable of being artificially formed, principally by the action of sulphuric and nitric acids on vegetable products which abound in carbonaceous matter. Yegetable Acids. The acid found in the juices and' other parts of plants, is not always the same. Not less than seven acids, different from each other, are of vegetable origin,—the Gallic, Oxalic, Malic, Citric, Tartaric, Benzoic and Acetic. To these may be added the Prussic, though this is more peculiarly formed from animal matter. Gallic Acid. The existence of this acid in some of the more powerful astringents, particularly in the gall nut, can be discovered by their watery infusion red- dening the infusion of litmus. If the concentrated infu- sion be left exposed to the air for some months, this acid is deposited in the state of a crystalline deposite, mixed with mucous flakes, from which it may be puri- fied. It may also be obtained by sublimation from the gall nut, or even by distillation with water, though it is doubtful whether, as procured, by these or other pro- cesses, it is altogether free from tannin; that by subli- mation appears to be more so. By crystallization it is ©btained in slender prisms of a white colour; its taste is Vol. I. G 50 OF THE GENERAL PRINCIPLES sour, and it reddens the vegetable colours; it is soluble in 24 parts of cold, and in less than 2 parts of boiling water; it is also soluble in alkohol. It suffers decomposition from heat, and the process indicates a large quantity of carbon in its composition. It combines with the alkalis and earths, and also with the metallic oxides, forming with the latter in general coloured precipitates; it is doubtful, however, whether these colours are not in a great mea- sure derived from the tannin adhering to it. Gallic acid was at one time supposed to be the prin- ciple of astringency, from being contained in the vege- table astringents, and giving a dark colour with the salts of iron, the chemical test by which astringency appears to be indicated. It is doubtful, however, as has just been remarked, whether this latter property does not arise from the presence of tannin: the colour it does produce is less deep too, than that which the infusion itself strikes; and the acid in its insulated state has no astringency. Tannin is much rather to be considered as the astringent principle, and it exists accordingly in some of the more powerful vegetable astringents, as in catechu or kino, with scarcely any trace of gallic acid. Malic Acid is contained in the juice of unripe ap- ples and other fruits; it is uncrystallizable, forming when evaporated merely a thick liquor, which, if the heat be continued, becomes charred. By this and by the properties of the salts which it forms, it is principally distinguished from the other vegetable acids. By nitric acid it is converted into oxalic acid. Citric Acid often accompanies the malic acid in the juices of unripe fruits, and it exists in a purer form in the juice of the lemon and lime from which it is ex- tracted; the mucilaginous matter of the juice being separated by alkohol. It crystallizes in rhomboidal prisms; which, when it is pure, are colourless; its taste is extremely sour; it is abundantly soluble in water; its solution undergoes spontaneous decomposition, but the crystallized salt can be preserved without injury. The more powerful acids decompose it, converting it prin- cipally into acetic acid. OF PHARMACEUTIC CHEMISTRY. Oxalic Acid exists in the juice of the sorrel (oxalis acetosella) and some other plants, combined with a por- tion of potash, not sufficient to neutralize it. It can also be artificially formed by subjecting fecula, gum, or sugar to the action of nitric acid. It crystallizes in slender prisms of a white colour; its taste is extremely sour; it is soluble in twice its weight of cold water, and an equal weight of boiling water; it is also soluble in alkohol. It is decomposed by the more powerful acids: in its de- composition by heat, it affords little empyreumatic oil; hence it appears to contain a small proportion of hydro- gen; and as some of the other vegetable acids are con- verted into it by the action of nitric acid, there is pro- bably a large proportion of oxygen in its composition. The test by which it is peculiarly distinguished, is the insoluble precipitate it forms with lime, which it attracts from all the other acids. Tartaric Acid. This acid, as it exists in vegeta- bles, is usually combined with potash, in such a propor- tion, however, as to leave an excess of acid in the combination. This forms the super-tartrate of potash which is contained in a number of vegetable fruits. It is deposited from the juice of the grape in its conversion • into wine, or in the slow fermentation which the wine suffers when kept. The acid procured from this salt is in tabular crystals, transparent; they are very soluble in water, the solution when concentrated being of an oily consistence. It is decomposed by heat, affording a large quantity of liquid acid little changed, with much' car- bonic acid gas. By nitric acid repeatedly distilled from it, it is converted into oxalic acid. This acid is an important one in pharmacy, from the numerous combi- nations of it applied to medicinal use. Benzoic Acid is obtained from the vegetable bal- sams, generally by the process of sublimation. It con- denses in slender crystals, white and brilliant. It is volatile, as this mode of preparation shows; its vapour is also inflammable; it is very sparingly soluble in cold water, but abundantly in hot water; the solution on cool- 5£ OF THE GENERAL PRINCIPLES ing depositing nearly the whole of the acid in prismatic crystals: it is also soluble in alkohol, from which it is precipitated by cold water; it is pungent, but not very acid to the taste; in its usual state its smell is fragrant, especially when it is heated: but this odour has been supposed to arise from a minute portion of the oil of the balsam adhering to it; as by repeated combinations with an alkaline base, and precipitation by an acid, it is ob- tained at length inodorous. It is not easily decomposed by the action of the more powerful acids. Decomposed by heat, it affords a larger quantity of empyreumatic oil than any other vegetable acid, whence hydrogen is sup- posed to predominate in its composition. Acetic Acid. This acid has been considered as more exclusively the product of fermentation; it exists like- wise, however, ready formed in the sap of the vine, and* combined with alkalis and earths, very generally indeed in the sap of plants. In its pure and concentrated state, in which state it can be procured only by artificial pro- cesses, it is a very powerful acid, highly pungent and fragrant, volatile and inflammable, and is distinguished by the peculiar action it exerts on some of the other proximate principles of plants,—essential oil, resin, gum-resin, camphor, gluten, and caoutchouc, which it dissolves without decomposing. Hence, even in its di- luted state, under the form of distilled vinegar, it is sometimes used as a solvent in pharmaceutic processes; though it is seldom that it can be employed to advantage, as it is liable to modify the powers of the substances it dissolves. Prussic Acid. The substance to which this name is given, is formed from some varieties of animal mat- ter by artificial processes. It had often been remarked, that its odour is similar to that of the peach blossom, and that the same odour is perceptible in the distilled water of the cherry laurel, and of the bitter almond* This led to experiments on these; whence the fact, rather singular, has been discovered, that all of them contain this acid. The fact, not less important, has been OF PHARMACEUTIC CHEMISTRY. 53 established, that the narcotic property possessed by these distilled waters depends on the prussic acid. In its insulated state, this substance is volatile, so that it escapes even from its watery solution under expo- sure to the air. It has no sensible sourness, and does not redden even the more delicate vegetable colours. The character of acidity is therefore given to it, rather from its powers in the combinations it forms, especially those with the metallic oxides, than from its properties in its insulated state. Several of the vegetable acids, particularly the citric, malic, and tartaric, exist together in the same vegetable, and in proportions varying according to the stage of vegetation, whence it is probable that they are mutually convertible. They seldom exist pure, but generally in combination with saccharine, mucilaginous, and extrac- tive matter. Combined with alkaline and earthy bases, they form what have been named the essential salts of plants. The last of the proper proximate principles of vege- tables is Lignin, or wood; the substance which, com- posing the vessels of the plant, is the basis through which the other principles are diffused, or to which they are attached, and which is the basis therefore of all the parts of vegetables, with the exception of their secreted juices. It is, when freed from the principles diffused through it, insipid, inert, and insoluble, liable in a humid state to slow spontaneous decomposition, inflammable, and decomposed by heat, leaving a large residuum of charcoal, which indicates carbon to be its predominant ingredient, whence probably arises its solidity and com- parative chemical inactivity. Being insoluble in water, or in alkohol, it forms the greater part of the residuum, when the active matter of vegetable substances has been abstracted by maceration in these solvents. Besides the principles which can thus be obtained in a distinct form from vegetables by analysis, there are others of a more subtle nature, which have been sup- posed to exist in vegetable matter, though scarcely 54 OF THE GENERAL PRINCIPLES capable of being exhibited in an insulated state; such are the Aroma or Spiritus Rector of plants, the Acrid Principle, the Bitter Principle, and the Narcotic Prin- ciple. The Aroma is the principle in which the odour of plants has been supposed to reside. This quality is generally found in the essential oil; but there are some vegetables, having a strong odour, which yield little or no essential oil, such as the jessamine, the violet, or the rose; or, if this oil be procured from them in small quantity, it has not that strength of odour which, con- sidering their fragrance, and the smallness of its quan- tity, might be expected from them. They exhale this odour, however, when exposed to the air; it is at length dissipated, or it is communicated to water by distillation at a very gentle heat. Hence it has been concluded, that a principle more subtle than the essential oil exists in which the odour resides, and that it is even this principle which communicates odour to the oil. These facts, however, are altogether inconclusive. The property of odour may belong to any of the proxi- mate principles of vegetables, and does belong to prin- ciples of very different kinds; it exists in other bodies in which we cannot suppose the existence of any common principle; nor is there any reason to assume the existence of such a principle in plants: and all the facts, which have been considered as favourable to the opinion, are accounted for on the supposition that essential oil is the more common principle of odour, and is capable of being volatilized in small quantity at a low temperature, and of thus being diffused through the atmosphere, or commu- nicated to water. The existence of an Acrid Principle has been inferred from an acrimony residing in some plants, which they lose on drying, while their other active powers remain; and from this acrimony being in some cases transferred to water or alkohol by distillation. It is not very cer- tain, however, if this quality is not in such cases con- nected with some of the known proximate principles; OF PHARMACEUTIC CHEMISTRY. 55 nor has this acrid principle, if it do exist, been obtained so as to submit it to chemical examination. A principle has been supposed to exist in some of the vegetable bitters in which their bitterness resides. It is obvious, however, that the quality of bitterness may be- long to any of the known proximate principles; and the qualities which have been assigned to this principle as it exists in some vegetables, particularly in gentian or quassia, such as equal solubility in water and in alkohol, and being precipitated by certain re-agents, rather prove it in these cases at least to be a variety of extractive matter. A Narcotic Principle has been supposed to exist, from the narcotic power of some vegetables being im- paired by age, without any apparent loss of matter, and from its being rendered inert by decoction, though no volatile matter is collected possessed of the quality. But such facts are rather favourable to the conclusion, that the loss of power is owing to chemical changes in one or other of the known principles, probably the extract, in which the narcotic quality may be supposed to reside. In submitting opium to analysis, it has been affirmed] that a crystalline matter is obtained, which proves narco- tic, and has been supposed to be the principle on which that quality possessed by the opium depends. But it does not, admitting its existence, appear to be possessed of the narcotic property in that high degree we should expect, were it the principle on which that property is dependent, nor is there any proof that it exists in any other narcotic. The existence of all these principles, therefore, is extremely problematical; and the qualities assigned to them may, with much more probability, be referred to modifications of composition in the known principles, which are probably too subtle to be ever determined by chemical analysis. 56 OF THE GENERAL PRINCIPLES Alkohol, and the Ethers formed from it by the action of acids, cannot be regarded as vegetable pro- ducts; yet they have a relation to these, as their chemical constitution is similar, and they cannot be formed but by changes produced in vegetable matter. As important medicinal, and pharmaceutic agents, they are entitled to notice. Alkohol is formed by the process of fermentation from saccharine matter, or from fecula, the latter being previously subjected, partially at least, to the operation of malting, by which it is in fact converted into the former. The fermented liquor being distilled, affords the alkohol formed during the process, diluted with water, and with some impregnation of odour from the fermented sub- stance. From this pure alkohol is procured by repeated distillation, the abstraction of the water from it being aided by the action of potash, or rather sub-carbonate of potash. Alkohol is a colourless transparent fluid, having a specific gravity, according to its state of concentration, from 0.835 to 0.800; it is fragrant and pungent, and in its action on the living system possesses a high degree of stimulant and narcotic power; it is volatile, and in- flammable, affording, during its combustion, no products but water and carbonic acid, the quantity of water ex- ceeding even the weight of the alkohol. It contains, therefore, much hydrogen in its composition, with which carbon is combined, and perhaps also a portion of oxy- gen. It combines with water in every proportion, and, in consequence of the affinity between these fluids, they mutually precipitate substances which either has dis- solved, that are insoluble in the other. It is decomposed by the acids, affording, as the principal product, the dif- ferent ethers. As a pharmaceutic agent, it is of much importance from the solvent power it exerts on a number of the vegetable proximate principles,—essential oil, camphor, extract, and others, and by its property too of counteracting the spontaneous changes to which vege- table matter is liable. OF PHARMACEUTIC CHEMISTRY. 57 Ether. The name Ether is given to a peculiar pro- duct obtained by the action of the more powerful acids on alkohol, the product differing in its properties ac- cording to the acid employed in its formation, but in general being extremely light, volatile, and inflammable. Sulphuric ether, formed by the action of sulphuric acid on alkohol, has a specific gravity not greater, when it is pure, than 0.716; it is so volatile as to evaporate rapidly at the common temperature of the atmosphere; in burning it affords water and carbonic acid: its odour is fragrant and penetrating; its taste pungent; it is solu- ble in water only in limited proportion, about one part in ten. It exerts on the vegetable principles the same solvent action nearly as alkohol, except on extract which it has been said to precipitate,—an effect, however, I have not been able to obtain from it. Nitric ether is equally light and even more volatile; it is inflammable; it is soluble in water in limited quantity, but combines with alkohol in every proportion: its odour is strong and penetrating. Muriatic ether is more volatile than either, existing in the state of gas, under the atmospheric pres- sure, at 60°; at 50 it becomes liquid, and its specific gravity is not less than 0.874; it is transparent, colour- less, odorous, and pungent. Acetic ether is moderately light, volatile, and inflammable, soluble in water in limited quantity, and has an odour ethereal, but ap- proaching also to that of vinegar. All these ethers appear to differ from alkohol, principally in having a larger proportion of hydrogen in their composition, to which probably their greater levity and volatility are to be ascribed; and they generally contain a portion of the acid by the action of which they have been formed, which, in some of them at least, appears essential to their chemical constitution. Having pointed out the distinguishing properties, and the general pharmaceutic relations of the Proximate Vol. I. H 58 OF THE GENERAL PRINCIPLES Principles of Vegetables, it may be proposed as a ques- tion important in relation to the object of the present outline, Do these principles usually exist in the vege- table in a state of chemical combination, whence some modification of their powers might result, or are they more generally mechanically mixed? The latter appears to be generally the case. These principles can often be observed existing apart from each other, and even placed in separate vesicles; they can in many cases be separated by mechanical means; and even where they are more intimately mixed, that change of properties does not take place, which we must have ex- pected were they chemically united, the virtues of each principle being discernible in the entire mixture, weak- ened, but not changed. It seems to follow, therefore, that the virtues of vegetable substances do not depend on chemical combinations of their proximate principles, but rather on the peculiar ultimate composition of one or other of these principles. Hence also it is evident, that in separating the proximate principles of any vegetable, we cannot expect to alter or improve its virtues, farther than in concentrating them by a separation from what is inert, or in separating principles which are possessed of different or even opposite powers. The attainment even of these ends, however, is, in innumerable cases, of im- portance in their exhibition as medicines. From this enumeration ofthe Proximate Principles of Vegetables, we may perceive the reasons for those phar- maceutic processes to which plants are usually subjected. Vegetable matter being liable to decomposition when in a humid state, from the re-action of its elements and their entering into new combinations, exsiccation is an operation to which they are generally subjected, to pre- serve them without injury. It is performed either by the action of a current of air, or by exposure to heat, care being taken that the heat shall not be such as to dissi- pate any of their volatile principles, or cause any chemi- cal change. By Infusion in water, the fluid is impregnated with OF PHARMACEUTIC CHEMISTRY. 59 the gum, sugar, extract, tannin, saline substances, part of the essential oil, and part also of the resinous princi- ple. The aroma of the plant is generally first taken up: by longer infusion the water is loaded with the colour- ing, astringent, and gummy parts: these are also most abundantly dissolved when the temperature is high. Hence an infusion differs according as the water has stood longer or shorter on the materials, and according as it has been promoted or not by heat. An infusion made in the cold is in general more grateful, while one made with heat, or by keeping the fluid long upon the materials, is more strongly impregnated with active matter. By Decoction or boiling, the solvent power of the water is still farther increased; and hence the liquor always appears darker .coloured, and is, in fact, more loaded with the principles of the vegetable which it can hold dissolved. The volatile parts, however, particu- larly the essential oil, are entirely dissipated; and there- fore it is an improper process for those vegetables whose virtues depend, wholly or partially, on these parts. Even the fixed principles of vegetables, at least some of them, are injured by long decoction. The extractive matter, for instance, gradually absorbs oxygen from the atmos- phere, and is converted into a substance nearly insipid and inert. Opium, Peruvian bark, and many other ve- getables, are injured in this manner by decoction, espe- cially if the atmospheric air is freely admitted; and these two circumstances, the dissipation of the volatile mat- ter, and the oxygenation of the extractive, considerably limit the application of this process. It is still used, however, with advantage, to extract the mucilaginous parts of vegetables, their bitterness, and several others of their peculiar qualities. Alkohol may be applied to vegetables to extract those principles which are not soluble in water. It dissolves entirely their essential oil, camphor, and resin; and as these are often the parts on which the virtues of vege- 60 OF THE GENERAL PRINCIPLES tables depend, these solutions, or Tinctures as they are termed, are often active preparations. Equal parts of alkohol and water, in general, extract still more completely the active matter of plants, as we thus obtain a solution of all those substances which are separately soluble in either of these fluids. When by the action of one or both of these fluids, we obtain a solution of the active principles of a vegeta- ble, the solution may be evaporated to the consistence of a thick tenacious mass. This forms what is termed an Extract: it is named an Aqueous Extract when ob- tained from the aqueous infusion or decoction of a plant, and Spiritous when alkohol has been the solvent. The design of this preparation is to obtain the active matter of the vegetable in a small bulk, and in such a state that it may preserved a long time without suffering any al- teration. It is evident, that it is a process which can be properly applied to such plants only as have their vir- tues dependent on some of their fixed principles, and even these are often injured by the heat applied, and the free access of the atmospheric air. Distillation is another process applied to vegetable substances, by which we obtain some of their active principles, particularly their essential oil. If the vegeta- ble matter be heated with a large portion of water, the oil is volatilized with the aqueous vapour: it separates from the water on being allowed to remain at rest; a part of it, however, is also dissolved, and communicates to the water a considerable degree of flavour, and often also of pungency. This forms what are named Distilled Waters. If alkohol be used instead of water, the essen- tial oil is completely dissolved in it, and we thus obtain what are termed Distilled Spirits. By such processes we extract the active matter of ve- getables from the inert matter with which it is more or less mixed, and are enabled to administer many reme- dies under a variety of forms, suited to particular cir- cumstances. A single example will show the utility of investigations of this kind, respecting the component OF PHARMACEUTIC CHEMISTRY. 61 principles of vegetable products, and their relations to the more important chemical agents. Peruvian bark is one of the most important remedies in the Materia Me- dica. Practitioners have not always found it practicable to exhibit it in substance with advantage, as where the stomach is uncommonly irritable, or where from the nature of the disease, it is necessary to give it in large doses, frequently repeated, it is apt to occasion sickness and other uneasy sensations, and even to be rejected by vomiting. Such inconveniencies are attempted to be ob- viated, by giving it in the different forms of infusion, decoction, tincture or extract, as any of these may be best suited to the case. Our knowledge of its consti- tuent parts can only lead us to the proper application of these processes. From an accurate analysis of this bark, it has been proved that seven parts out of eight consist of woody fibre, or of a matter inert and insolu- ble, which cannot act on the system, and which affects the stomach only by its weight and insolubility. The remaining eighth part is that in which the activity of the medicine resides: it is therefore evident that if this be extracted, without injuring its activity, the medicine could be exhibited with much more advantage. This is in part accomplished by the preparations of it that have been mentioned; but even these do not convey it in all its force. If one ounce of the bark be infused or boiled in a certain quantity of water, the infusion or de- coction is not nearly equal in efficacy to the whole quantity of bark operated on. It is therefore evident, that during either of these operations, the active matter of the bark has not been entirely extracted, or has suf- fered some change. And here Chemistry lends her assistance, and still farther elucidates the peculiar na- ture of this substance, and the changes produced in it by these processes. It has been proved by experiment, that the matter on which the power of the bark de- pends, has a strong attraction for oxygen at a tem- perature moderately increased; that during the infusion, and particularly during the decoction of that drug, this active matter absorbs oxygen from the atmosphere, and 62 OF THE GENERAL PRINCIPLES is converted into a substance insipid and inert. This leads to the improvement of the preparations of this medicine; and experiments instituted for the pur- pose have accordingly proved, that, while byT long boil- ing the virtues of the bark are nearly totally destroyed, they are fully extracted by a few minutes' decoction in covered vessels. The same investigations have pointed out the nature of the action of some other substances on bark, formerly not well understood. Thus, it has been found by experience, that the alkalis, and more parti- cularly magnesia, enable water to extract the virtues of bark, more completely by infusion,—a circumstance elucidated by the fact since discovered, that the ex- tractive matter of the bark, to which its activity is owing, combines with facility with these substances and forms soluble compounds. Similar examples might be given from several other important vegetable remedies, which would sufficiently prove the utility to be derived from the analysis of the substances belonging to the vegetable kingdom, and that indeed researches of this kind are absolutely necessary for their proper preparation as medicines. The account of the analysis of animal substances, and of their proximate principles, would, to the same extent at least, be foreign to the objects of this sketch, as so few of these substances are employed in medicine; and of those which are used, the composition and con- sequently the pharmaceutic treatment, are in a great measure peculiar to each. Their general chemical characters are similar to those of vegetable principles.—Composed of a few ultimate elements, the differences in their properties arise in a great measure from the different proportions, or the dif- ferent modes in which these are combined. And these elements having powerful reciprocal attractions, and being disposed to enter into combinations almost in- definitely diversified with regard to these circumstances, these substances are extremely susceptible of decompo- sition, from the re-action of their elements, favoured by OF PHARMACEUTIC CHEMISTRY. 63 humidity, by the action of the air, or by elevation of temperature. They are even more liable to this than vegetable substances; for their elements existing in simultaneous combination are more numerous, their affinities are therefore more nicely adjusted, and of course the equilibrium is more easily subverted. Along with carbon, hydrogen, and oxygen, which are the chief constituent principles of vegetable matter, nitrogen, and frequently sulphur and phosphorus, enter into the composition of animal substances. Hence, when decomposed by heat, they afford products composed of these, of which ammonia is always the principal; and the re-action of these principles, and the evolution of the products arising from this, seem principally to form the series of changes which constitute putrefaction, the spe- cies of spontaneous decomposition to which animal matter is more peculiarly subject. Like vegetable substances, the animal products con- sist of various proximate principles, and some analogy may be traced between several of the vegetable and animal proximate principles. Animal fat has a strict connection in properties and composition with fixed oil; animal mucus resembles vegetable mucilage; fecula has a similar relation to gelatin; vegetable and animal gluten are nearly if not entirely the same; a substance similar to saccharine matter exists in milk, and in some of the other animal secretions: in the bile is found a principle strictly analogous to resin; and benzoic, oxalic, and acetic acids are common to both. Hence, generally speaking, the few animal substances belonging to the Materia Medica are acted on by the usual solvents in nearly the same manner as vegetable substances, and are submitted to similar pharmaceutic processes. The result of these are similar officinal preparations. Thus by the action of alkohol, the active matter of musk, castor, and cantha- rides is extracted, and tinctures of these are employed. In other cases water is the proper solvent, particularly of those which consist of gelatin; but such solutions being very liable to decomposition, must always be of extem- poraneous preparation. 64 OF THE GENERAL PRINCIPLES CHAPTER II. OF THE PHARMACEUTICAL OPERATIONS TO WHICH THE ARTI- CLES OP THE MATERIA MEDICA ARE SUBJECTED. Natural substances, it has been remarked, are not always obtained in that state in which they are best adapted to exhibition as remedies. They are subjected, therefore, to various processes, with the view of pre- serving them, or of preparing them for use; and to complete this statement of the Principles of Pharma- ceutic Chemistry, the nature of these is to be pointed out. These processes, or at least the greater number, and the most important of them, are chemical, and are de- pendent therefore on the agencies of those general forces whence chemical changes arise; they are indeed little more than applications of these, under peculiar regula- tions adapted to different substances. The general facts, therefore, connected with the operation of these forces, are first to be stated, in so far as they have any relation to the present subject. The force principally productive of chemical action, is that species of attraction exerted between the parti- cles of bodies, which brings them into intimate union. If two substances of different kinds be placed in contact, and with that degree of fluidity which admits of the par- ticles of the one moving to those of the other, it often happens that they unite together, and form a substance in which neither can be any longer recognised, and which is homogeneous, and in general possessed of new properties. This constitutes what, in the language of chemistry, is named combination, and is conceived to arise from an attraction exerted between the particles of the one body to those of the other. It is this which is denominated Chemical Attraction or Affinity, and OF PHARMACEUTIC CHEMISTRY. 65 which is distinguished from the other species of attrac- tion by the phenomena to which it gives rise, or by the laws it obeys,—from the attraction of gravitation, by not being exerted at sensible distances, or on masses of matter, but only at insensible distances, and on the mi- nute particles of bodies,—from the attraction of aggre- gation, by being exerted between particles of different kinds, and forming a substance with new properties, while that force operates on particles of a similar nature, and of course unites them into an aggregate in which the same essential properties exist. It is possible that these forces, though thus distinguished, may be the re- sult of the same power modified by the circumstances under which it acts. The substance formed by chemical combination is named a compound. The substances united are the constituent or component parts or principles of the compound. When these are separated, the process is named decomposition. The most minute parts into which a body can be resolyed without decomposition, are named its integrant parts; and it is between these that the force of aggregation is conceived to be exerted. Chemical attraction is exerted between the constituent parts. The most important phenomenon attending chemical combination is a change of properties. In general, the form, density, colour, taste, and other sensible qualities, as well as the fusibility, volatility, tendency to combi- nation, and other chemical properties in the compound, are more or less different from what they are in either of its constituent parts, and frequently indeed they are wholly dissimilar. There are cases, too, however, where the change is less considerable, as is exemplified in se- veral of the operations of Pharmacy,—the solution of the vegetable proximate principles in water or in alkohol, or the solution of baits in water, in which the body acquires mereh the liquid form, with perhaps a slight change of density, but in which no important property is changed, nor any new one acquired. Vol. I. I 66 OF THE GENERAL PRINCIPLES Chemical attraction is not an invariable force exerted by every body to every other, and always with the same degree of strength. Between many substances* it does not sensibly operate, though this perhaps may be owing to the predominance of external circumstances, by which its operation is influenced, rather than to the absence of all mutual attraction. It is exerted too by each body to- wards others, with different degrees of strength. It is not limited in its action to two bodies, but is frequently exerted at the same time between three, four, or a greater number, so as to unite them in one combi- nation. Such compounds are named Ternary, &c. ac- cording to the number of their constituent principles; they are abundant among the productions of nature, and can be formed also by the arrangements of art. This force is exerted too, so as to combine bodies in more than one proportion; and, from the union of two substances in different proportions, compounds are form- ed frequently as dissimilar in their properties as if they were composed of principles totally different. In some cases, the combination is unlimited with regard to pro- portions; in others, it is fixed to two or three relative quantities, and there are examples where it can be esta- blished in only one proportion. The opinion has been maintained, and is probably just, that the tendency of chemical attraction is to unite bodies indefinitely with regard to proportion, and that determinate proportions are established only by the operation of external forces. The compounds formed by the exertion of chemical attraction have apparently the same relation to this power as simple bodies have: they have a similar tendency to combination, unite in different proportions, and with different degrees of force; and all these combinations are accompanied by the same phenomena, and appear to observe the same laws. It has been supposed, how- ever, that when compound substances combine toge- ther, the combination is the result, not of the mutual attraction between the integrant particles of these com- OF PHARMACEUTIC CHEMISTRY. 67 pounds, but of the affinities of their ultimate elements modified by the condition in which they exist. In all cases, attraction is much modified, and its results determined by circumstances foreign to the at- tractive force itself. The operation of these circum- stances has been established with more precision by the labours of Berthollet, and been proved to be more im- portant than was formerly believed. They require, therefore, more distinct enumeration, especially as some of them give rise to important results in the processes of Pharmacy. 1st. Quantity of matter influences affinity, an increase in the relative quantity of one body with regard to ano- ther enabling it to act with more force; or, as the law has been stated, " every substance having a tendency to " enter into combination, acts in the ratio of its affinity "and its quantity." Hence an effect can be produced from the mutual action of two bodies, when one is in a certain relative proportion to the other, which will not be obtained when the proportion is changed,—a cir- cumstance of much importance in Pharmacy, requiring, in particular, attention towards insuring the uniform strength of active preparations; and of much influence too on the results of chemical decomposition, rendering it frequently partial, where it was supposed to be com- plete. 2d. Cohesion, or the state of a body with regard to the aggregation of its integrant particles, must obviously modify the chemical action of another body upon it, by opposing a resistance which must be overcome before the union of their particles can be effected; hence the cause, that two solid bodies seldom act chemically on each other, and that fluidity promotes chemical action. But besides this obvious effect, cohesion, even when it has been overcome, still modifies the exertion of che- mical attraction, by resuming its force whenever the force of that attraction is diminished, and thus some- times giving rise to new combinations; and sometimes too, when suddenly established in consequence of the 68 OF THE GENERAL PRINCIPLES affinities becoming effective, it determines the propor- tions in which bodies combine, by insulating the com- pound at a certain stage of the combination. It is thus the most powerful cause in placing limits to the exertion of chemical attraction. Insolubility is merely the result of the force of cohesion, in relation to the liquid which is the medium of chemical action, and its action is of course similar; and great Density, or specific gravity, so far as it influences attraction, operates in nearly the same manner, counteracting it, by withdraw. ing the substances between which it is to be exerted from the sphere of mutual action. 3d. Elasticity, or that property of bodies arising from repulsion between their particles, and present to any extent only in those existing in the aeriform state, opposes the exertion of chemical attraction, by enlarging the distances at which these particles are placed. Hence aerial fluids combine in general with difficulty; and hence too, a compound which contains an ingredient which, when insulated, assumes the aerial state, is more easy of decomposition, and the decomposition is more complete, than a compound, the ingredients of which are fixed; for the tendency to elasticity in the volatile ingredient counteracts the mutual affinity; and when, by the appli- cation of heat, or the operation of a superior attraction, any portion of it is displaced, by assuming the elastic form it is withdrawn from the sphere of action, and ceases to oppose any obstacle by its affinity or quantity to the progress of the decomposition. Elasticity too, by counteracting attraction, places limits to the proportions in which bodies combine. 4th. The last circumstance influencing attraction is Temperature, or the state of a body with regard to heat or cold, which sometimes favours, and in other cases subverts combination. The cause of temperature is a peculiar subtle power or principle, (in modern che- mical language denominated Caloric), capable of being communicated to bodies, and of being in part at least withdrawn from them. Its immediate tendency is to OF PHARMACEUTIC CHEMISTRY. 69 establish a repulsion between their particles; hence it gives rise to expansion or enlargement of volume, greater in each body according to the quantity of caloric introduced. This progressive augmentation of distance, at which the particles are placed by its action, is accom- panied with a proportional diminution in the force of cohesion; if carried, therefore, to a certain extent, that force is so far modified, that the particles become capa- ble of moving easily with regard to each other,—a state which constitutes fluidity; and, if the communication of caloric be continued, the expansion still continuing, the particles are at length placed at such distances, that the attraction is entirely overcome, and they repel each other,—a state which constitutes the aerial or gaseous form. The operation of ealoric in influencing chemical attraction, appears to depend on the changes it occa- sions in the cohesion and elasticity of bodies,—favour- ing combination by diminishing cohesion, counteracting or subverting it by communicating or increasing elas- ticity; these effects too being often produced together, and modifying each other. From the differences of the forces of affinity among bodies, or still more perhaps from the operation of those circumstances by which affinity is modified, its power is often suspended or overcome, and substances which have been combined are separated. This forms what in Che- mistry is named Decomposition, and it presents results equally important with those from combination. The decomposition may be simple, that is, a com- pound may be resolved into its constituent parts, each of which is insulated. This is in general effected by the agency of heat. Within a certain range of temperature, the affinity which has combined two bodies continues to operate; but when the temperature is raised, and when the bodies differ in their volatility, or the tendency they have to assume the elastic form, the elasticity of the more volatile one is so far favoured by the elevated tern* perature, that the mutual affinity is overcome, and it is disengaged. It is generally obtained pure; but the fixed 70 OF THE GENERAL PRINCIPLES substance, from the influence of quantity on chemical attraction, frequently retains a portion of the other com- bined with it. Decomposition is more complicated when it is pro- duced by the introduction of a third substance, which exerts an attraction to one of the ingredients of a com- pound. When this is effective, the body added com- bines with this ingredient, forming a new compound, and it is only the other ingredient of the original compound that is obtained insulated. A case still more complicated is, where two compound substances are brought to act on each other, and the principles of the one exert affini- ties to those of the other; so that an interchange lakes place, the two compounds are decomposed, and two new ones are formed. Both these kinds of decomposition are likewise materially modified by the state with regard to temperature. The former case used to be named by chemists single elective attraction; the latter double elec- tive attraction; and both were considered as the results of the relative forces of attraction among the bodies con- cerned. But there is reason to believe, that they arise from the operation of cohesion, elasticity, and the other forces that influence attraction; and that but for the ope- ration of these forces, three or more bodies presented to each other would enter into simultaneous union, instead of passing into binary combinations. Galvanism, as well as caloric, influences chemical affi- nity, and, by the attractive as well as by the repulsive force it exerts, is even more powerful in producing decomposition. It scarcely admits, however, of being applied to any pharmaceutic process. The operations of Pharmacy are generally depend- ent on these chemical powers; they consist of arrange- ments of circumstances, with the view either of pro- moting their exertion, or of obtaining the products of chemical action. Some preliminary operations are frequently had re- course to of a mechanical nature, to diminish the cohe- sion of bodies, or enlarge their surface. Such are Pul- OF PHARMACEUTIC CHEMISTRY. 71 verization, Trituration, Levigation, Granulation, &c. Pulverization is the term employed where solid bo- dies are reduced to powder by beating: Trituration that where the same effect is produced by continued rubbing. Levigation denotes the operation where the powder is rubbed to a still greater fineness, the rubbing being facilitated by the interposition of a fluid, in which the solid is not soluble. As by any of these operations, the powder must consist of particles of unequal size, the finer are separated from the coarser by sifting or wash- ing. Sifting is passing the powder over a sieve, the in- terstices of which are so minute as to allow only the finer particles to pass. Washing or Elutriation, is an operation performed only on substances which are not soluble in water. The powder is diffused through a quantity of that fluid, and the mixture is allowed to re- main at rest. The coarser particles quickly subside, and the finer remain suspended. It is then decanted off, the powder is allowed to subside, and is afterwards dried. These methods of reducing bodies to powder, can be ap- plied to very few of the metals, their force of cohesion being too strong. They are mechanically divided by rasping, or by being beat into leaves, or they are granu- lated,—an operation performed by melting the metal, and when it is cooled down as far as it can be, without becoming solid, pouring it into water: it passes to the solid state, assuming the granular form. In Pharmacy, these operations are sometimes of im- portance, besides merely promoting chemical combina- tion, as there are some medicines which act with more certainty, and even with more efficacy, when finely levi- gated, than when given in a coarse powder. As means of promoting chemical combination, it is evident, that they can act only indirectly; the bodies being far from being reduced to their minute particles, between which only chemical attraction is exerted. They are therefore employed, merely as preliminary to those operations in which such a division is obtained by che- mical means. 72 OF THE GENERAL PRINCIPLES Of these, the first is Solution. By this is understood that operation in which a solid body combines with a fluid in such a manner that the compound retains the fiuid form, and is transparent. Transparency is the test of perfect solution. When the specific gravity of a solid body differs not greatly from that of a fluid, it may be diffused through it, but the mixture is more or less opaque; and on being kept for some time at rest, the heavier body subsides; while in solution the particles of the solid are permanently suspended by the state of combination in which they exist, and are so minute as not to impair the transparency of the liquid. The liquid has, in this case, been regarded as the body exerting the active power, and has been named the Sol- vent or Menstruum; the solid is considered as the body dissolved. The attraction, however, whence the solution proceeds, is reciprocal, and the form generally proceeds from the larger quantity of the liquid employed, and from the absence of cohesion being more favourable to the combination proceeding to a greater extent. In general, the solution of a solid in a liquid can be effected only in a certain quantity. This limitation of solution is named Saturation; and when the point is reached, the liquid is said to be saturated with the solid. As the fluid approaches to saturation, the solution pro- ceeds more slowly. When a fluid is saturated with one body, this does not prevent its dissolving a portion of another; and in this way three, four or five bodies may be retained in solution at the same time by one fluid. In these cases, the fluid does not dissolve so large a propor- tion of any of these substances, as if it had been per- fectly pure, though sometimes the whole proportion of solid matter dissolved is increased from the mutual affi- nities the bodies exert. Neither is the solvent power always thus limited, there being many cases where a solid may be dissolved in a fluid to any extent. Gum or sugar, for example, will dissolve in water, and form a perfect solution in every proportion. An increase of temperature, in general, favours solu- OF PHARMACEUTIC CHEMISTRY. tion, the solution proceeding more rapidly at a high than at a low temperature; and in those cases in which a certain quantity only of the solid can be combined with the fluid, a larger quantity is taken up when the tempera- ture is increased. The quantity dissolved is not in every case promoted alike by an increase of temperature; wa- ter, for example, having its solvent power, with regard to nitre, greatly increased by augmentation of tempera- ture, while sea salt is dissolved in nearly as great a quan- tity by water at a low as at a high temperature. This difference in these salts, and in many others, depends on the difference in the degree of their fusibility by heat; those which are mosteasily fused having their solubility in water most largely increased by increase of tempera- ture. All these facts, indeed, with regard to solution, are explained, by considering this operation as depending on chemical affinity overcoming cohesion in the body dissolved. Agitation favours solution, by bringing successively the different parts of the liquid into contact with the solid, and thus preventing the diminished effect which arises from the approach to saturation in the portion immediately covering the solid. The mechanical division of a solid too, is favourable to its solution, principally by enlarging the surface which is acted on. Solution is an operation frequently had recourse to in pharmaceutical chemistry, the active principles of many bodies being dissolved by their proper solvents. Salts are dissolved in water, as are also gum, extract, and other vegetable products. Products of a different kind, as resin, camphor, and essential oils, are dissolved in alkohol and wine; and metals are rendered soluble and active by the different acids. Solutions in water, alkohol, or wine, possess the sensible qualities and medical virtues of the substance dissolved. Acid and alkaline liquors change the properties of the bodies which they dissolve. In Pharmacy, the operation receives different appellations, according to the nature of the solvent, of the substance dissolved, and of the manner in which it is performed. Vol. I. K U- OF THE GENERAL PRINCIPLES When a fluid is poured on any vegetable matter, so as to dissolve only some of its principles, the operation is named Extraction, and the part dissolved is said to be extracted. If it is performed without heat, it is termed Maceration; if with a moderate heat, Digestion; if the fluid is poured boiling hot on the substance, and they are kept in a covered vessel till cold, this is denominated Infusion. Decoction is the term given to the opera- tion when the substances are boiled together. It is evi- dent, that these are all instances of solution, varied only by particular circumstances; and I have already stated, under the analysis of the vegetable part of the Materia Medica, the advantages belonging to each. Lixivia- tion is the term applied to solution performed on saline substances where the soluble matter is separated, by the action of the solvent, from other substances that are in- soluble; and the solution obtained in this case is named a Ley. The other principal method by which that fluidity necessary to chemical action is communicated, is Fu- sion. It requires, merely with regard to each sub- stance, the necessary degree of heat; and where this is high, it is performed usually in crucibles of earthen ware, or sometimes of black lead, or on a large scale in iron pots. Chemical combination is frequently promoted by an elevation of temperature, though the heat may not be so high as to produce fusion, but only to diminish co- hesion to a certain extent. Calcination, as it used to be named, or metallic oxidation, is an example of this; a metal being heated to a high temperature, so as to enable it to combine with the oxygen of the air. Deflagration is a similar operation, an inflammable or metallic substance being exposed to a red heat in mixture with nitre: the acid of the nitre yields its oxygen; which being thus afforded in large quantity and nearly pure, the oxidation takes place with rapi- dity, and generally to its maximum. When chemical action has been exerted, other opera- OF PHARMACEUTIC CHEMISTRY. 75 tions are sometimes required to obtain the product, or sometimes this product is formed and collected in the operation itself. By Evaporation, or dissipating a liquid by the application of heat, a solid substance which has been dissolved in it is recovered, and this operation is one frequently performed in Pharmacy. When performed on a small scale, vessels of glass, or of earthen ware, are generally employed, and the heat is applied either by the medium of sand, or if it is required to be more moderate, the vessel is placed over water which is kept boiling, forming what is named the Water Bath, or Balneum Maria. When performed on a larger scale, shal- low iron pots or leaden troughs are used, to which the fire is directly applied; and experiments have shown that the operation is conducted more economically when the liquor is kept boiling strongly, than when it is evaporated more slowly by a more gentle heat. There is, on the other hand, however, some loss, from part of the dissolved substance being carried off when the heat is high, by its affinity to the liquid evaporating; and in many cases in Pharmacy, particularly in the evaporation of vegetable infusions or tinctures, the flavour, and even the more active qualities of the dissolved substance, are liable to be injured, especially towards the end of the operation, by a strong heat. When the object is to obtain the volatile matter by evaporation, the process is of course conducted in close vessels adapted to condense the vapour and collect the liquid. This forms the operation of Distillation, which, with regard to different substances, requires to be conducted in various modes. When a volatile principle is to be obtained from ve- getable substances by this process, the difficulty is to apply the heat sufficiently without raising it too high. The mode generally employed is to heat the vegetable matter with water, and the distillation is then usually performed in the common still. At the heat of boiling water, the essential oil of plants, which is the chief vo- 76 OF THE GENERAL PRINCIPLES latile principle they contain, is volatilized; it rises with the watery vapour; is condensed; if little water has been employed, the greater part of the oil is obtained apart; if much has been used, it retains it dissolved, acquiring taste and flavour, and thus forming the dis- tilled water of plants. If alkohol, pure or diluted, has been the medium of distillation, it always retains the oil in solution, and forms what are named Distilled Spirits. The still in which the operation is performed with these views is of copper or iron; it consists of a body and head, the former designed to contain the materials, and to which the fire is applied, the latter to receive the vapour; there issues from it a tube, which is connected with a spiral tube, placed in a vessel, named the refrigeratory, filled with cold water. The vapour, in its progress through the tube, is condensed, and the liquid drops from the extremity of it. When metallic matter would be acted on, by the ma- terials or the product of distillation, vessels of glass or earthen ware are employed; the retort, which is gener- ally used being connected with a single receiver, or with a range of receivers, according as the vapour is more or less easily condensed; or, if the product is a perma- nently elastic fluid, which cannot be condensed but by passing it through water, a series of bottles connected by tubes, on the principle of Woolfe's apparatus, is used. When the product obtained by distillation is not per- fectly pure, it can be frequently purified by a second distillation; the process is then named Rectification: when it is freed from any superflous water combined with it, the operation is named Dephlegmation or Con- centration. When the product of volatilization is condensed, not in the liquid, but the solid form, the process is named Sublimation, and the product a Sublimate. As the condensation takes place with much more facility, a more simple apparatus is employed, consisting usually of a conical bottle or flask with a round bottom thin and equal, named a Cucurbit, in which the materials are OF PHARMACEUTIC CHEMISTRY. 77 contained, heat being applied by the medium of a sand bath. The vapour condenses in the upper part of the flask, forming a cake, which adheres to it, the orifice being lightly closed to prevent any part from being lost; or a globular head, with a groove at its under edge, and a tube to convey off any liquid that may be condensed, (a Capital as it is named,) being applied. When a solid substance is thrown down from a liquid by chemical action, it forms the operation of Precipi- tation, and the matter thrown down is named a Preci- pitate. Frequently the substance precipitated is one which had been dissolved in the liquid, and which is separated by a substance added, combining with the liquid, and weakening its attraction to the one which it held in solution. Or sometimes it arises from a com- pound being formed by the union of one body with another, which is insoluble in the liquid that is the me- dium of action. The precipitate is allowed to subside, is usually washed with water, and is dried. From the law of chemical attraction, that quantity influences the force of affinity, it often happens that the precipitate either retains in combination a portion of the substance by which it had been dissolved, or attracts a portion of the substance by which it is thrown down, and this sometimes proves a source of impurity, or of peculiar powers in medicinal preparations. When a substance, in passing to the solid state, as- sumes a regular geometric form, the process is named Crystallization, and these figured masses are de- nominated Crystals. Their forms are various, though nearly constant with regard to each substance; they are usually transparent, hard, and have a regular internal structure. The crystallization may happen in two ways, from a state of solution. If a saturated solution has been prepared with the aid of heat, the increased quantity of the solid, which the heat has enabled the liquid to dis- solve, separates as the temperature falls; and the attrac- tion of cohesion being thus slowly exerted between the particles, unites them so as to form crystals. Or, if a 78 OF THE GENERAL PRINCIPLES portion of the solvent be withdrawn by evaporation, and especially by slow evaporation, the particles of the solid unite slowly, and with a similar result. In both these kinds of crystallization from a watery solution, the crystallized substance always retains a quantity of water, and frequently even a considerable proportion, in its composition. It is essential to the con- stitution of the crystal, its transparency, structure and form, and is hence named the Water of Crystallization. Some crystals lose it from mere exposure to the air, when they are said to effloresce; others attract water, and become humid, or deliquesce. Crystallization is promoted by the mechanical action of the air; likewise by affording a nucleus, whence it may commence, and especially a crystal of the substance dissolved; and with regard to a few substances, their affinity to the solvent requires to be diminished by the addition of another substance to enable them to crys- tallize. In Pharmacy, crystallization is of importance, by enabling us to obtain substances, especially those be- longing to the class of salts, in a pure form; different salts, even when present in the same solution, being thus separated by their different tendencies to crystallization, according as they are more or less soluble in the solvent, or have their solubility more or less promoted by heat, and each salt, when it does crystallize, being in general pure. These are the principal operations of Pharmacy. Con- nected with this subject, there remain to be noticed the weights and measures which are usually employed. The division according to what is named Troy weight, is that ordered in the Pharmacopoeias. Its parts, with the symbols by which they are denoted, and their rela- tive proportions, are represented in the following table: 12 ounces. 8 drachms. 3 scruples. 20 grains (grann) gr. A pound (libra), ffe An ounce (uncia), ? A drachm (drachma), 5 A scruple (scrupulus),9 OF PHARMACEUTIC CHEMISTRY. 79 Measures have been subdivided in a similar manner, being made to correspond to the specific gravity of water. As the specific gravities of liquids vary, how- ever, considerably, a source of error is introduced in applying the standard measure to different liquids, unless the due allowance be made for the difference in specific gravity. This it is to be presumed will often be ne- glected, and hence the Edinburgh College have rejected the use of measures, and given the proportions of every liquid by weight. The use of measures, however, in apportioning liquids, being more easy and convenient, will probably always be retained; and the London Col- lege have therefore, in the late edition of their Pharma- copoeia, sanctioned their use. They adopt measures subdivided from the wine gallon, as represented with their symbols in the following table: A gallon (congius), "\ g r 8 pints. A pint (octarius), O / -3 j 16 fluidounces. A fluidounce (fluiduncia), f5 f c 1 8 fluidrachms. A fluidrachm (fluidrachma), 13 3 u ( 60 minims, (minima) nt- This last measure is one newly introduced. In appor- tioning liquids into very small quantities, the quantity has been usually estimated by drops (gutta, gtt) allow- ed to fall from the edge of the mouth of a bottle; but the size of the drop is liable to vary much, not only accord- ing to the mobility and specific gravity of the liquid, a circumstance of little importance, since with regard to each substance it remains the same, but also according to the thickness of the edge and degree of inclination. The London College have therefore substituted this di- vision of minims, which are measured in a slender gra- duated glass tube. The measures of a table and of a tea-spoonful are sometimes used in extemporaneous prescription, and, though not very accurate, may be admitted where a small difference in the dose is not im- portant. The one is understood to be equal to half an ounce by measure, the other to about one drachm. 80 PART II. OF MATERIA MEDICA MATERIA MEDICA, in the extensive signification which has sometimes been attached to the term, com- prizes the history both of Aliments and of Medicines. It is used, however, and more correctly, as opposed to the Materia Alimentaria; and in this limited sense may be defined that department of Medicine, which describes the properties, and investigates the effects on the living sys- tem of those substances, which are employed as remedies against disease,—substances which are not necessary to the immediate support of the functions of life, to repair the waste of the body, or furnish matter whence its se- cretions are derived, but are more peculiarly adapted to excite actions in the system, or produce changes, with a view to the removal of morbid states. It includes the history of these substances, independent of the pre- parations to which they are subjected to fit them for administration, this belonging to the department of Phar- macy. 81 CHAPTER I. preliminary observations on the objects op study in the history of the articles of the materia medica, and on their classification. The subjects of enquiry, in the study of the articles of the Materia Medica, may be comprized under their Natural History, their Chemical History, and what may be more strictly denominated their Medical History. The utility of Natural History in furnishing ap- propriate characters by which the productions of nature may be distinguished from each other, is abundantly obvious; and its application to the articles of the Ma- teria Medica is under this point of view indispensable. From want of such characters, the remedies described by the ancient physicians cannot now in many cases be accurately ascertained: did we not possess them, our observations would in the progress of time be liable to the same inconvenience; and the accurate distinctions which the methods of natural history afford, are at pre- sent necessary to discriminate between substances which have a near resemblance to each other, or to describe with accuracy the remedies employed in different coun- tries. This subject has likewise been considered under a higher point of view. From attention to the characters of the articles of the Materia Medica, as they are ob- jects of natural history, it has been supposed, that assistance may be derived in the investigation of their virtues; these being sometimes indicated by their natu- ral affinities. In artificial systems of classification, the discriminating characters are taken from one or two re- markable properties possessed by a certain number of bodies, and these are arranged together, though they may differ widely in the general assemblage of their Vol. I. L 82 MATERIA MEDICA. qualities. In the natural method, the arrangement is founded on the occurrence of a number of characters taken from what is essential to the substance; the gra- dations of nature are observed, and those bodies are arranged together, which in their general appearance, nature and qualities have a close resemblance. It is the prosecution of this natural method that has been sup- posed useful in ascertaining the medicinal virtues of the productions of nature,—a supposition not unreasonable, since, where there exists a natural resemblance in struc- tures and qualities, it might be inferred that there may be a resemblance in medicinal powers. In the vegetable kingdom especially, this natural affinity has been industriously traced and applied to this purpose. Those vegetables which agree in their general structure, habit, and appearance, are thrown into what are named Natural Orders or Families; and experience has shown, that the individuals composing many of these natural orders, have a remarkable similarity in their effects on the system. In the subdivisions of the order, this analogy is not less striking, the different species having in general similar virtues. If, therefore, a new species of any of these genera be discovered, the disco- verer may infer with some probability a priori, that it will possess virtues similar to those of the genus to which it belongs. This criterion of the virtues of medicines, though un- doubtedly so far just, is however liable to many excep- tions. Many natural orders are composed of vegetables, which, though they agree in structure, have the most various and opposite qualities; and even in those in which there is in general the greatest similarity, there are found wide differences in the properties of many plants arranged under them. Even in the subdivision of the genus, there is often a remarkable difference in the properties of the species; and what sufficiently points out the deficiency of this method, different parts of the same plants have often opposite powers. Yet it is to be admitted, that with ail these exceptions, Na- PRELIMINARY OBSERVATIONS. 83 turalists have often been led by such analogies to just conclusions respecting the virtues of plants; and in studying the vegetable part of the Materia Medica, attention is undoubtedly due to these natural dis- tinctions. A part of the Natural History of Medicines, of still more importance than their generic and specific cha- racters, is the accurate description of their sensible qualities. Such descriptions afford the most abvious method of distinguishing them, and in many cases also the most easy and certain criterion of their purity and perfection. A knowledge of these qualities is not less necessary, as it leads to their proper administration, since, from the peculiar qualities of taste, flavour, specific gravity, or consistence in any substance, one form may be better adapted to its exhibition than another. It has also been imagined, that the -sensible qualities of medicines, particularly their taste and smell, lead to indications of their peculiar powers, and experience to a certain extent confirms this supposition. In the vege- table kingdom especially, it has been found, that sub- stances which are insipid and inodorous rarely possess any considerable medicinal virtues, and a number of such substances have justly been discarded from prac- tice from attention to this circumstan :.e: their insi- pidity having led to suspicion of their activity, and oc- casioned a more strict examination of the evidence on which their supposed virtues were said to be established. On the other hand, plants possessing much odour or taste, are in general active remedies; and those which resemble each other in these qualities, have often the same general medicinal powers: astringency is indicated by a styptic taste, bitters are tonics, aromatics are stimu- lating, and foetids narcotic. There are, however, so many causes of obscurity and error in these indications, that they do not admit of very extensive accurate application. The different tastes and odours are so little reducible to precise definition 34 MATERIA MEDICA. or description, that few general rules can be formed from them; and even to the few that have been delivered on this subject, there are many exceptions. The most ac- tive vegetable substances too, have not these properties more peculiar than many others comparatively inert, and hence it is not often that much assistance can be derived from this criterion of the virtues of plants. The Chemical History of the articles of the Ma- teria Medica forms another important general object of investigation. The opinion seems to have been early adopted by those who cultivated chemistry with a view to its ap- plication to medicine, that those substances which agree in their action on the system must be composed of the same principles, and that therefore chemical analysis may be a successful method of investigating their me- dical virtues—an opinion not altogether unreasonable. The properties of any compound depend on its peculiar chemical composition; they originate from that compo- sition, and are altered by every variation which it suf- fers. The medicinal powers of such substances must, in common with their other qualities, depend on the same cause; and it is not unreasonable to presume, that where similar powers exist, they arise from similarity of composition, either with regard to the constituent principles, or to the peculiar mode in which these are united. Confiding in the justness of these conclusions, the chemists, about the beginning of the 17th century, be- stowed much labour on the analysis of the different vegetables us»ed in medicine. Above 500 plants were analyzed; but had even the analysis been performed with all those essential precautions, which it was im- Eossible that the state of Chemistry at that period could ave furnished, the nature of it was such, that it could lead to no useful information. The plants subjected to analysis were exposed to heat, and the products collect- ed; but as these products do not pre-exist in the vege- table, but are formed by new combinations of its ele- PRELIMINARY OBSERVATIONS. 85 ments, and as these elements are in all vegetables nearly the same, no connection can be traced between them and the qualities of the substance from which they are obtained. It was found accordingly, that the most inert and the most poisonous vegetable afforded the same products; and if the experiment were now repeated with all the advantages of the rigorous methods of Modern Chemistry, no information useful to the physician would be obtained. Similar proximate principles of different plants, though possessed of different medicinal powers, would give similar results; or if any difference were ob- served, it would be impossible to connect this with the difference in their powers. Nor can we expect from the chemistry, at least of our times, to be able to discover on what chemical principle, or what peculiarity of com- bination, the peculiar powers of any active vegetable productions depend; for although these, in common with other qualities, may arise from chemical composi- tion, yet the varieties of combination from which they may be supposed to derive their origin, are too minute to be detected by our modes of analysis. The pretensions of Modern Chemistry, as applied to Materia Medica, are therefore more humble, but they are more just. By discovering those proximate princi- ples of vegetables in which their active powers reside, and enabling us to separate them from each other, or from other inert and noxious matter with which they may be mixed, it allows us to -apply them with much more advantage: it determines how far in every case such operations are useful: whether the principles thus operated on are altered by these operations, and by what means such alterations, if injurious, may be obviated. Similar advantages are obtained from its application to the few products of the animal kingdom that are em- ployed in medicine; and those belonging to the mineral kingdom can be used with much more advantage and discrimination, when their nature has been ascertained by analysis, than when we are left to collect their virtues from experience. 86 MATERIA MEDICA. By the combinations which Chemistry regulates, it furnishes us with many remedies which owe to these combinations their sole power, and which are equally active with many of those afforded by nature. Lastly, it has taught us the proper methods of administering these substances. Many of them exert a mutual action, com- bine together, or decompose each other; and were such facts which Chemistry discovers not precisely known, important errors would frequently be committed in their mixture and administration. The last object in the study of the Materia Medica, that to which the others are merely subservient, is their Medical History, or the investigation of the virtues and uses of remedies. This comprehends several im- portant subjects of inquiry. There belongs to it the consideration of the action of those substances on the system in its healthy state; since, when this is ascertained, it leads to their application to the treatment of disease. It may in general be affirmed, though the principle is not without exception, that sub- stances which do not act sensibly on the body in a healthy state, will not prove active remedies; and that, on the contrary, every substance which is capable of producing any important change in the system, must be more or less extensively adapted to the removal of morbid affections. Another subject of inquiry, scarcely less important, relates to the mode in which remedies act, and by which they produce their peculiar effects. It is not sufficient merely to have ascertained by the evidence of experience the virtues of certain remedies in certain cases. It is of importance, farther, to arrange the facts thus collected; to institute some comparison between remedies pos- sessed of nearly the same general power, and, so far as can be done, to investigate their mode of operation, with the view of extending their application, and of ad- ministering them with ihore precision. Lastly, with regard to what may be more strictly termed the medicinal powers of remedies, there are a number of subjects of consideration of importance. It PRELIMINARY OBSERVATIONS. 87 is necessary to take notice of the applications for which each individual article is distinguished; the forms of disease to which it is adapted; the circumstances that may influence its operation, or in certain cases render its exhibition doubtful or improper; the cautions neces- sary in its use; the dose in which it is given; the usual and proper forms of exhibition; and the effects of the combinations of remedies with each other. These observations point out the subjects to which the attention is principally to be directed in the study of the articles of the Materia Medica. Very different systems have been followed, according to which these substances are arranged. The two which are least exceptionable, and which are possessed of un- doubted advantages, are that founded on their natural distinctions, and that resting on their medicinal powers. The latter ground of classification appears more sys- tematic, and more conformable to the object of the study itself, than any other. These substances are subjects of inquiry, merely as possessed of certain medicinal pro- perties: they ought to be classed, therefore, it might be concluded, on principles conformable to this: and by founding the classification on this basis, some important advantages are obtained: we are enabled to place toge- ther the remedies which are possessed of similar virtues, to deliver the theory of their operation, to compare the powers of the individual substances arranged under the class; and by a reference to this generalization, to point out more distinctly their degrees of activity, and the peculiarities which may attend the operation of each. The principal difficulty which attends it, is one arising perhaps from our imperfect knowledge of the laws of the animal economy, and of the operation of remedies, in consequence of which we cannot always assign their primary action, but are often under the necessity of arranging them from their more obvious, though secon- dary effects. Hence, as many substances are capable of producing various effects of this kind, and are actually employed in medicine to obtain this diversity of effect, 88 MATERIA MEDICA. the same substance frequently requires to be considered under different classes, and under each its history is incomplete. It may be capable of acting, for example, as an emetic, as a cathartic, and as a diuretic: did we know precisely the primary operation of it, whence these effects arise, this might serve as the basis of its classification; but this being unknown, and the classifi- cation being established on these secondary operations, it must necessarily be placed under each of these classes, and under each its history is imperfect, as it must be limited to the operation which gives the character of the class under which it is arranged. In a course of lectures this is extremely inconvenient; the history of almost every important article of the Ma- teria Medica being placed under different divisions, fre- quently remote from each other, and no distinct and complete view of it being delivered. But in a treatise, to the different parts of which it is easy to refer, this is of less importance, and is more than compensated for by the other advantages of which this method of classifica- tion is possessed. And when the merits of two modes of classification are so nearly balanced, it is even of import- ance to exhibit the subjects connected with them under the points of view which each mode more peculiarly affords. It is this classification, therefore, which is fol- lowed in the present work. 89 CHAPTER II. GENERAL VIEW OF THE OPERATIONS OF MEDICINES, AND OF THEIR CLASSIFICATION FOUNDED ON THESE OPERATIONS The advantages of an arrangement of the articles of the Materia Medica, founded on their medicinal ope- rations, I have stated under the preceding observations; and in endeavouring to exhibit this branch of medicine, strictly as a science, it is that undoubtedly which ought to be followed. The difficulty of constructing such an arrangement, has at the same time always been expe- rienced. No subject is involved in greater obscurity, than what relates to the action of substances on the liv- ing system. Their effects are not always easily appre- ciated with accuracy, especially in a state of disease, and our knowledge of the laws of their action is extremely imperfect. When we attempt, therefore, to class them according to these actions, we can scarcely form an arrangement strictly just and systematic, but are forced to admit of some deviations, and to be guided not un- frequently by imperfect analogies. The difficulty of constructing a classification of medi- cines from their operations, will be apparent from the failure even of Cullen, when he attempted the execution of this task; for there can now be little hesitation in affirming, that the one he has given rests on principles nearly altogether false. The following table represents this classification: Vol. I. M 90 GENERAL VIEW OF THE O < u t—( Q 1 S 3< Simplicia. 7om'oz. Emollientia. Erodentia. Viva. Stimulantia. Sedantia. Narcotica. Refrigerantia. Antispasmodica. S'lmmutantia. fFluiditatem. I Attenuantia, Inspissantia. ^Misturam. Acrimoniam corrigentia. In genere. Demulcentia. In specie. Antalkalina. Antiseptica. vJEvacuantia. Errhina. Sialogoga. Expectorantia. Emetica. Cafhartica. Diuretica. Diaphoretica. Menagoga. Now, without examining it minutely, it may be re- marked, that the basis of this classification, the assump- tion that some medicines act exclusively on the solids, others on the fluids of the body, is incorrect; for, with the exception of two or three classes, the action of the OPERATIONS OF MEDICINES. 91 whole is on the living solids. Thus, emetics, cathartics, diuretics, diaphoretics, emmenagogues, expectorants, sialogogues and errhines produce their effects, unques- tionably by no operation on the fluids which they eva- cuate, but by exciting a particular organ to action. The distinction is equally nugatory in the greater number of cases between the action of medicines on the simple solids and on the living solids. It cannot be doubted, but that tonics produce their effects in removing debility, not as the hypothesis of Cullen assumes, by any action on the inanimate fibre of the body, giving it density or tone, but by their operation on the vital powers of the system. Nor can the effects of astringents be ascribed entirely to their corrugating quality. In this arrangement too, are placed classes of medi- cines which have probably no real existence, the action ascribed to them being merely hypothetical. We may be allowed to question the existence of attenuants and inspissants,—medicines which render the fluids of the body more thin, or which produce the opposite effect. Nor is there any reason to believe in the reality of antiseptics. The process of putrefaction probably never takes place in the living body; and if it did, we know of no medicines by which it could be retarded or counter- acted.* In the system of Brown, which succeeded that of Cullen, more just views were given of the relations of external agents to the living system, and of the laws regulating their action. The operations of medicines, however, are even in this system imperfectly explained, principally, perhaps, from its author having surveyed all the parts of his subject with those views of generali- zation which nearly preclude all minute distinctions. Medicines he supposed to operate merely as other ex- ternal agents, by exciting to action either the general * That putrefaction does not take place in the living body has ^ been most conclusively proven by a series of well-conducted expe- riments. Vid. Seybert's Inaugural Thesis. University Penn. 1793. Ed. 92 GENERAL VIEW OF THE system, or the particular organs on which they operate; and to differ from each other in little more than in the degree in which they exert this stimulating power. They have, farther than this, no specific properties, but are adapted to the removal of morbid affections, merely by producing excitement, partial or general, with certain degress of rapidity or force. This proposition is far from being just, at least in an unlimited sense. Medicines, and even external agents, in general unquestionably differ, not only in degree, but in kind of action. Every substance applied to the organs of sense, gives a different sensation, not referrible to the mere force of the impression, but which must be attri- buted to some essential varieties in the modes of action of the agents themselves. Every organ is excited to its usual or healthy action only by its appropriate stimu- lant. It is the same with regard to medicines, or diffe- rences in the kind of action they exert are not less con- spicuous. Opium and mercury both excite the actions of the system, and so far agree in their general opera- tion. But the ultimate effects they produce are extremely dissimilar, nor from either of them can we, by any vari- ation of dose, or mode of administration, obtain those which usually result from the action of the other. All the important articles nearly of the Materia Medica, might be brought forward as similar examples, and as proving, that they are not to be regarded simply as sti- mulants varying in strength, but that their action is modified by peculiar powers they exert. Still the principles of this system approach to the truth, and appear most conformable to the laws which regulate the animal economy, and, with some modifica- tions, they may perhaps be applied so as to afford a more satisfactory view of the operations of medicines, and foundations for arranging them under different classes. If we attend to the general operation of medicines, we find, that it is that of exciting to action, either the general system or particular organs. This is the primary effect; and to express the agency of the substance pro- OPERATIONS OF MEDICINES. 95 ducing it, the term of stimulant operation may be em- ployed. And, according to the kind and degree of this stimulant operation, different effects will be produced, the discrimination of which may afford several import- ant distinctions. Thus, of those stimulants which act on the general system, the operation is extremely different with regard to diffusibility and permanence. Some are highly diffusi- ble in their action, or, soon after they have been received into the stomach, they produce increased vigour, which is immediately conspicuous in the force of the circula- tion, the nervous system, or the different functions of the body; while, with regard to others, the same general effect is produced more slowly, and is scarcely percepti- ble but from their repeated or continued administration. Those which are diffusible are at the same time gene- rally transient in their operation; while those which pro- duce excitement more slowly, are generally more per- manent. And by both diversities of action, it is obvious their operation must be productive of very different effects: the high excitement produced by the one is generally immediately followed by proportional lan- guor; the gradual excitement from the other, being reduced more slowly, they occasion no such sudden changes, but are fitted to produce more lasting effects. These varieties of action serve, accordingly, to explain the differences in the power of some of our most im- portant medicines, and they afford the distinction of two principal classes, Narcotics and Tonics; the one, so far as their action is understood, being apparently stimulants, diffusible and transient, the others slow and permanent. Another important difference among stimulants, is de- rived from the action of some being general with regard to the system, while that of others is more peculiarly directed to particular organs. The effect with regard to either is not easily explained; but the fact is certain, that some substances, as soon as they are received into the stomach, not only produce on k a stimulant effect, but 94 GENERAL VIEW OF THE extend this to the general system; while there are otherar which, without any very evident action on the stomach, and still less without any general action, excite particular organs: some, for example, stimulating the intestinal ca- nal, others exciting the action of the secreting vessels of the kidneys, and others operating on the exhalant vessels of the skin. These, which are given as examples, afford the distinctions of cathartics, diuretics, and diaphoretics, and there are other classes founded on similar local ope- rations. With this local action, many substances exert, at the same time, more or less of a general operation, by which the individuals of a class become capable of pro- ducing peculiar effects, and many of them, by pecu- liarity of administration, act specifically on more than one part of the system, by which their effects are still more diversified. When medicines are thus determined to particular parts, they are either directly conveyed, by being re- ceived into the blood, or their action is communicated indirectly from the stomach, by the medium of the ner- vous system; and in both ways important local effects are often produced. Thus, there are many substances which appear to be capable of being so far assimilated with the food, as to enter into the composition of the chyle, and are received into the circulating mass. Being brought, in the course of the circulation, to particular organs, they often excite in them peculiar actions. Mercury affords an example of this. It enters the circulation, and when accumulated to a sufficient extent, generally acts on the salivary glands. It is on secreting organs that these local effects are usually produced, and frequently the substance is separated with the secreted fluid, so as to be brought to act on the secreting vessels in a concentrated state. Such is the case with the alkaline salts, or with nitre, which are secreted by the vessels of the kidneys, sti- mulate them at the same time to action, and are capable of being detected in the secreted fluid by chemical tests. But the most general mode in which the operation of OPERATIONS OF MEDICINES. §5 medicines taken into the stomach is extended, either to the system in general, or to any particular part, is by the medium of nervous communication. An impression is made on the fibres of the stomach by the substance re- ceived into it, and however difficult it may be to con- ceive the mode in which this can be communicated by the nerves to distant parts, the fact is undoubted, and established by the plainest evidence. It is evident from the effects of these substances being produced in a shorter time after they have been received into the stomach, than they could be were they to act by being absorbed with the chyle into the circulating mass. The stimulus of wine or of opium received into the sto- mach will instantly remove lassitude, and increased the vigour of the circulation, or of muscular exertion. Digi- talis given to sufficient extent will very speedily reduce, to a great degree, the frequency of the pulse; or a large dose of cinchona, given half an hour before the expected recurrence of the paroxysm of an intermittent, will prevent its attack. It has also been proved by ex- periment, that this communication of action from the stomach to other parts, in a number of cases, does not take place where the brain and spinal marrow have been destroyed, though the heart and vascular system have been preserved uninjured. From this susceptibility of impression, and of com- municating action to other parts, the stomach becomes an organ of the first importance, since, independent of its being the vehicle by which substances are conveyed into the blood, it is that by means of which medicines are brought to act on the system by the medium of the nerves. It sometimes happens, however, .that a similar extension of action may take place from other parts; and hence effects may be obtained from medicines, by ap- plying them to the surface of the body, similar to those which they produce when they have been received into the stomach. Sometimes the effect is conveyed by ner- vous communication, and sometimes the substance ap- plied is absorbed by the lymphatics, and enters the 96 GENERAL VIEW OF THE blood. Examples of the first are to be found in many narcotics. Opium, applied to the skin, either in the solid form, or in that of tincture, often relieves pain, and removes spasmodic affections, either general or local. Tobacco applied to the region of the stomach excites vomiting; and garlic applied to the feet acts as a power- ful stimulant, and raises the strength of the pulse. Ex- amples of the second mode of operation are still more frequent. Friction on the surface is a common method of introducing mercury into the system. By the same means oxide of arsenic, tartrate of antimony, and va- rious other active substances, may be introduced; a so- lution of them in water being rubbed on the palms of the hand; and in certain circumstances this is preferable to their administration by the stomach. These are examples of the various relations which medicines bear to the living system. We are unques- tionably altogether unable to assign a cause for these peculiar properties, to ascertain why the action of some should be extended to the system in general, or why that of others should be determined to particular parts, either where substances enter the blood, or where they act by the medium of the nerves. But from the possession of such properties, it is evident, that their powers as medicines must be more diversified than if they were merely general stimulants, varying in the' degree of their stimulating power; and farther, that dis- tinctions are thus afforded for establishing a variety of classes. Another cause remains to be pointed out, by which the actions of medicines are diversified. Besides acting as stimulants, they often occasion changes, either me- chanical or chemical, in the state of the fluids, or of the simple solids, and these changes are productive of me- dicinal effects. This operation of medicines was formerly supposed to be much more extensive than it really is. Theorists, uninformed of the laws of animal life, were not suf- ficiently aware of the important fact, that the actions of OPERATIONS OF MEDICINES. 97 medicines on the living body are governed by laws different from those which regulate the actions exerted between the masses or particles of inanimate matter. Hence we find in their speculations constant attempts to trace the causes of diseases to changes merely me- chanical or chemical, to plethora or obstruction, to laxity or rigidity, to the abundance of acid or of alkali, or to the presence of other specific acrimonies still less defined. Their explanations of the operations of medi- cines were of course founded on these notions, and hence the distinctions of inspissants, attenuants, anta- cids, antalkalies, antiseptics, and several others with which their Materia Medica was loaded. These errors are now nearly exploded. We have learned to consider the living system as endowed with peculiar properties and modes of action, incapable of being explained on mere mechanical or chemical prin- ciples; and to regard external powers acting upon it as producing changes conformable to these peculiar pro- perties of life. Yet still we can sometimes refer a salu- tary change, effected in the system, or in particular organs, to changes mechanical or chemical in the solids or fluids. Thus, symptoms arising from irritation may be removed by lubricating the irritated surface: acid in the stomach may be corrected by the exhibition of alka- lies or absorbent earths; and urinary concretions may be dissolved, or at least their increase may be prevented, by the use of alkaline remedies. These properties of certain medicines are not perhaps highly important; but still they demand attention, and they afford sufficient distinctions for the formation of several classes. In conformity to these views, the classification of the articles of the Materia Medica, founded on their medi- cinal operations, may be established. It is only neces- sary to observe, principally to obviate hasty criticism, that in classifications founded on this principle, perfect precision is not to be expected. The science of medi- cine is still in so imperfect a state, particularly in what regards the relations of external agents to the living sys- Vol.I. N 98 GENERAL VIEW OF THE tern, that both in arranging the classes, and associating the substances which we place under each, we must frequently rest satisfied with remote analogies, which will not always bear a strict examination. This is an imperfection at present unavoidable; it must either be submitted to, or such modes of classification must be altogether rejected; and the question therefore ultimately is, not whether these arrangements are unobjectionable, but whether the advantages belonging to them are not such as to justify their adoption even with all their im- perfections.* * The preceding account of the modus operandi of medicines, is on the whole, more correct than any which I have met with. Ex- cepting indeed, that part of it which alleges that certain articles produce their effects on distant portions of the body, by being con- veyed to them through the medium of the circulation, I can find little in the statement of which I do not entirely approve. The hypothesis to which I allude, is evidently a relict of the hu- meral pathology. By the disciples of that sect, it was held, that disease chiefly consists in a depravation of the blood, " from too great tenuity or viscidity, by an excess of acid or alkaline acri- mony, by morbific matter entering from without, or generated within, by processes analogous to fermentation or putrefaction." As a necessary consequence of this view of disease, medicines were supposed to enter the circulation, and by a sort of chemical action to correct the vitiated condition of the fluids, and hence the origin of the terms inspissants, attenuants, antacids, antalkalies, antiseptics, diluents, demulcents, &c To demonstrate the fallacy of these speculations, by any detail of facts or reasonings, cannot now be required, as they are pretty generally exploded My opi- nion is, that all changes in the condition of fluids are wrought by impressions made through the intervention of the solids. Not the slighest proof exists, so far as I know, of their undergoing any mu- tations either by spontaneous action, or from the introduction of foreign matters, much less that such is the cause of disease, or the mode in which our remedies operate To penetrate into the circulation, medicines must pass either by the lacteals or lymphatics. Now, it seems more than probable, in cither case, their powers would be so neutralised by the prepara- tory processes of animalization as to be deprived of all activity. Can it indeed be credited, that any substance, after a subjection to the digestive and assimilative powers, retains, in the slighest de- gree, its original properties? Experiments, on the contrary, shew, that chyle, however diversified the material ma be out of which it is formed, whether animal or vegetable, has invariably an identity OPERATIONS OF MEDICINES. 99 Under the first division of the arrangement I pro- pose, may be placed those substances which exert a general stimulant operation on the system. Of these of nature, and instead of being a crude, as is commonly imagined, is in reality, a highly elaborated fluid, having many, and perhaps all the properties of blood, except its red colour. Three of the constituent parts of blood, it at least contains. 1. There is one portion of chyle, which preserves its fluidity during life, but coagulates after death, by exposure to the air, and is probably fibrine. 2. There is a second portion, which resembles serum in conti- nuing fluid when exposed to the atmosphere, and in coagulating at the same degree of temperature as serum. 3. There is a third, consisting of globules, similar to those of the blood, with this difference only, that they are much more minute. The fact of the perfect and uniform constitution of chyle seems to me, at once, to put down the hypothesis which I am combating. But, perhaps, it may be said it proves nothing in the case of medi- cines administered other ways than by the stomach, as when ap- plied to the surface of the body, or introduced into the bowels. To this objection, the answer is obvious, and I think very satisfactory. No one who has carefully attended to the phenomena of the ab- sorbent system can help admitting, that every section of it is en- dowed with the power of digestion and assimilation, and the lym- phatics quite as conspicuously as the lacteals. This capacity is given as a provision of nature, to exclude noxious matters from the circulation. The absorbents in most instances are fully adequate to this end, and where they are not, the substance penetrates to the first conglobate gland which takes on inflammation, and arrests its further progress, these organs acting here, as centinels, guard- ing the exterior approaches of the body. That some of the properties of certain articles, as the odour of garlic, and the colouring matter of madder, are displayed in the se- cretions and excretions, I am not disposed to deny. But, it does not hence follow, that these substances entered the circulation in their primitive shape. Directly the reverse indeed seems to be proven, as neither the one nor the other can be detected in the serum of the blood.* To me it is clear, that the process of assimi- lation, as performed either by the chilopoietic viscera, or by any part of the absorbent apparatus, completely decomposes all sub- stances, and however discrepant in their properties, reduces them to one homogeneous fluid, fitted for the purpose of nutrition. But when thrown into the secretions or excretions, being removed beyond the sphere of the vital energies, the chemical affinities * Vid. Hodge's Inaug. Thesis, printed in the year 1801 100 GENERAL VIEW Of THE there are two subdivisions, the Diffusible and the Perma- nent; the former including the class of Narcotics, with which may be associated, as not very remote in their sometimes are again brought into play, by which, these substances are in part, or wholly regenerated. Whether this explanation be received or not, it must, at least, be acknowledged, that no substance, in its active state, does reach the circulation, since experiments have shewn, that even a few drops of the mildest fluid, as milk or mucilage, oil or pus, cannot be injected into the blood vessels, without occasioning the most fatal consequences. Conceding however to the humeral pathologists all which their doctrine demands, still insuperable difficulties remain in the way of its adoption to account for the operation of medicines. Not to dwell tediously on this subject, I shall content myself at present, with merely mentioning that we are not at all informed by it, why our remedies after mixing with the blood should be directed to one organ in preference to another, as mercury to the salivary glands, &c. As regards the mercurial preparations, the example particularly selected by our author to illustrate his hypothesis, there is the most conclusive proof that they, in whatever manner employed, are not carried into the circulation*, and no doubt, such is the case with all the articles of the Materia Medica. It results, therefore, from what I have said, that we are to reject the fluids altogether in our inquiries relative to the operation of medicines, because, in addition to the reasons already stated for doing so, we have, in that law of the animal economy, called sympathy or consent of parts, a solution of the problem, infinitely more consistent with the existing state of our knowledge. Conformably to this theory, whenever a medicinal substance is applied to a susceptible portion of the body externally or internally, an action is excited, which is extended more or less, according to the diffusibility of the properties of the substance, or the degree of sympathetic connection which the part may maintain with the body generally. Thus, a set of actions is raised, every one of Avhich is precisely similar, provided they are confined to the same system, by which is to be understood, parts of an identity of struc- ture. If, however, the chain runs into other systems, it loses its homogeneous character, the actions being modified by the peculiar organization of the parts in which they may take place. These are principles of universal application. In every case, whether it re- spects the operation of remedies or the production of disease, the spot primarily acted upon is a point from which is diffused the radiated impressions.—Ed. * Vid: experiments of Drs. Phv9ick and Seybert, Medical Repostorv, Vol. v. OPERATIONS OF MEDICINES. 101 operation, the class of Antispasmodics; the latter com- prising two classes, Tonics and Astringents. Through these there is a gradual transition from the most highly diffusible stimulant to those most slow and durable in heir action. A second division comprehends Local Stimulants,— those the action of which is determined to particular parts of the system. Such are the classes of Emetics, Cathartics, Emmenagogues, Diuretics, Diaphoretics, Expectorants, and Sialogogues; with which may be associated the classes of Errhines, and of Epispastics, founded on direct local application. The remaining classes include substances which do not operate according to laws peculiar to the living sys- tem. To one division may be referred, those, the effects of which depend on the chemical changes they produce in the fluids or swlids: the classes which may be established on this principle are Refrigerants, Antacids, Lithontrip- tics, and Escharotics. To another division belong those, the operation of which is purely mechanical,—Anthel- mintics, Demulcents, Diluents, and Emollients. Under these classes may be comprehended all those substances which are capable of producing salutary changes in the human system, and which are used as remedies. A view of this classification is exhibited in the following table: 102 TABLE OF CLASSIFICATION. A. General Stimulants. tao- -ui C Narcotics. a. Diffusible. £ Antispasmodics. b. Permanent. £ A^ngents. B. Local Stimulants. Emetics. Cathartics. Emmenagogues. Diuretics. Diaphoretics. Expectorants. Sialogogues. Errhines. Epispastics. C. Chemical Remedies. Refrigerants. Antacids. Lithontriptics. Escharotics. D. Mechanical Remedies. Anthelmintics. Demulcents. Diluents. Emollients. From this arrangement, some classes.are excluded that have usually found a place in others; but these have either appeared to me not essentially different from those that arc admitted, or to have been founded on false or hypothetical distinctions. There is no great advantage in extending the arrange- ments into systematic subdivisions of the classes. The substances under each may follow each other according to their natural affinities, their chemical relations, or analogies in medicinal power less important than those which form the basis of the class itself; and in the dif- ferent classes one of these methods will frequently be found better adapted to any purpose of utility than the others. That which gives the most natural arrangement may therefore always be followed. 103 FIRST DIVISION. OF GENERAL STIMULANTS. THIS division, according to the preceding table of classification, includes the four classes of Narcotics, Antispasmodics, Tonics, and Astringents,—these agree- ing in the general stimulant operation they exert on the system, and differing principally in the diffusibility and permanence of action. They are therefore strictly con- nected, at least so far as to form a series through which the transition is easily traced. CHAPTER III. OF NARCOTICS. Narcotics, according to the definition that has Usually been given, are substances which diminish the actions and powers of the system without occasioning any sensible evacuation. This definition is imperfect, in as much as it does not include that stimulant operation which they equally produce, and which in part at least must be admitted as the cause of these effects. The term Narcotic is the most unexceptionable that can be assigned to these remedies. They are also named Seda- tives, from their power of diminishing action; Anodynes, from their capability of alleviating pain; and Hypnotics, or Soporifics, from their power of inducing sleep. The following are the general effects resulting from the operation of Narcotics. In a moderate dose they in- 104 NARCOTICS. crease the force and frequency of the pulse, promote the secretions, give vigour to the body, and rouse the fa- culties of the mind, rendering its conceptions more vivid and forcible, and inducing hilarity or intoxication. These effects are however only temporary, and after some time symptoms of an opposite kind make their appearance; the pulse not only returns to its former standard, but becomes more slow, and at the same time full and soft; the respiration is more easy; the secretions, ex- cepting that by the skin, are diminished; pain and in- ordinate motion, if present, are alleviated or repressed: there is a general languor, averseness to motion, and dullness of sense: the mind is placid and inactive, a state which generally soon terminates in sleep. This, after continuing for some time, is succeeded by temporary delibility, marked by some degree of sickness, tremors, anxiety, and oppression. If the dose has been large, these symptoms of diminished sense and action are in- duced, even without any previous increased action; or, if a still larger dose has been given, the immediate con- sequences are delirium, paralysis, convulsions, coma, and death. These effects are considerably diversified, as arising from different Narcotics. In some, any stimulant ope- ration is scarcely preceptible, even in a very moderate dose; others, with the narcotic power, possess an acrid quality; and in a large dose, with the general effects above enumerated, induce irritation or inflammation of the stomach, by which their action is modified. Some are more apt to induce sickness than others; and there is reason to believe that there are others in which the action is not equal upon the nervous and vascular sys- tems, but is more determined to the one than to the other. The medicines belonging to this class evidently act primarily upon the stomach, whence their action is pro- pagated by nervous communication to the rest of the system. That they do not act by being received into the blood is evident from the fact, that their effects are NARCOTICS. 105 apparent in general in a very short time, after they have been swallowed; and it has been ascertained by experi- ments, that if dissection be made immediately after these effects have appeared, the whole of the quantity administered is found in the stomach undissolved. Applied externally, these medicines often exert their usual action, though with much less force. Opium ap- plied to the skin deadens pain, and represses spasmodic muscular action, not only in the part to which it is im- mediately applied, but in others more distant. Several others of this class have similar effects. Narcotics applied to the muscles of animals, quicken at first their action; but in a very short time they exhaust all irritability and sensibility. The heart even of cold- blooded animals is deprived of all power of motion by the application of a strong solution of opium for a few minutes. When injected into the blood vessels, the ani- mal instantly dies without convulsions, and all the mus- cles of the body, voluntary or involuntary, are totally deprived of the power of contraction. There is a singularity in the operation of narcotics, that by repetition their action on the system is di- minished more than that of any other class of medicines, so that, after having been used for some time, they re- quire to be given in increased doses to produce their usual effects, and quantities of them have at length been taken, which at first would have destroyed life. No very satisfactory explanation has been given of this singularity, for it is not connected with any proportional reduction of irritability, or any apparent permanent change in the system; but the fact is generally true with respect to these medicines, and requires to be attended to in their administration. It appears too to be more pe- culiarly the case with some than with others. The theory of the operation of narcotics is attended with considerable difficulty, and very different opinions have been maintained with regard to it. As they in general diminish the actions of the system, when given even in a small dose, it happened, that from Vol. I. O 106 NARCOTICS. their exhibition those effects were in general most ob- vious, and their stimulant operation was more rarely ob- served. Hence their primary action was generally con- sidered as of a depressing kind, and they were described by authors under the appellation of Sedatives. The stimulant effects which were also observed to arise from their action, were ascribed to what was termed the re-action of the system. It was supposed, that there belonged to the animal frame a power, the tendency of which is to resist and obviate the effects of any thing noxious. If such an agent were applied, this principle was believed to be roused into action, and all the powers of the system were excited to throw off the noxious application. On this hypothesis, the action of narcotics was attempted to be explained by Cullen. Their natural tendency was supposed to be to depress the powers of life; if given in a large dose, this power was exerted with effect, and hence arose symptoms of exhaustion; but, if given in a smaller dose, the vis me- dicatrix, or preserving power, was enabled to resist, and by its resistance occasioned the symptoms of increased action that first appeared. These substances, therefore, were considered as directly sedative, and as indirectly stimulant. Precisely the reverse of this view was advanced by Brown, narcotics being regarded as stimulants, surpass- ing all others in the diffusibility and little durability of their action, and on this principle their effects were ex- plained in the following manner. It is the necessary effect of stimulant operation, to produce for a time increased action, but as this is at- tended with a diminution of vital power, the excite- ment soon ceases, and diminished action succeeds. These effects are proportional, partly to the absolute force of the exciting power, and partly to the rapidity with which it operates. If sufficiently strong, and if, at the same time, it be diffusible and transient in its opera- tion, the excitement it produces is quickly raised to its highest point, and is as quickly followed by proportional NARCOTICS. 107 languor and diminished action. Or if the dose is large, the stimulant effect is so rapid, as to be hardly per- ceptible, and hence the sedative or depressing effects only appear. Thus narcotics were regarded as powerful stimulants, whose action is not confined to the part to which they are applied, but is rapidly extended over the system. In a moderate dose, they promote action of every kind, which is succeeded by a degree of languor or delibilit), proportioned to the excitement that had been raised; and in a large dose, they produce diminution of power, and consequently of action, with- out airy symptom of previous excitement. Hence they were regarded as directly stimulant and indirectly se- dative. If in investigating this subject, we merely contrast these two theories, little doubt can remain of the supe- riority of the latter. The former is founded on an hypo- thesis established by no evidence, that a power presides over the system, ready to resist every noxious applica- tion; the latter is apparently more strictly deduced from the properties of the substances whose operation is to be explained: for as it is proved, and indeed admitted, that the stimulant operation resulting from the exhibi- tion of narcotics follows immediately, and previous to any symptoms of languor and debility, these ought strictly to be considered as the consequences of the for- mer. The most extensive analogy too has been traced between the operation of narcotics, and other sub- stances allowed to be stimulant, but which are less rapid in their action; as for example, between ardent spirit and opium, though in the one, the stimulant, in the other the sedative operation is usually more appa- rent. And, lastly, the advantage derived from the cau- tious administration of narcotics in some diseases qf diminished action, is scarcely compatible with the sup- position of their exerting a direct depressing power. The principal difficulty attending the theory, appears to arise from the fact apparently established, that the se- dative power of these substances does not appear to be 108 NARCOTICS. always proportional to their stimulant operation, but is greater than this, and that in several of them any pre- vious stimulant effect is even scarcely perceptible. Yet this difficulty is in some measure obviated by the ac- knowledged fact, that substances, the stimulating action of which is unquestionable, as ardent spirit, if given in a very large dose, produce depression without any pre- vious perceptible increased action. In like manner, electricity, applied in moderate quantity, stimulates the muscular fibre to contraction; while applied in a highly concentrated state, it instantaneously produces total ex- haustion of the contractile power. The more forcibly, therefore, a stimulant operates, the more rapid does the immediate action appear to be produced, and the more quickly to cease, so as to be followed by the second- ary effect; and with the admission of this principle, may perhaps be explained on this hypothesis, the fact, that the sedative effects of narcotics appear often to be greater than their previous stimulating operation; the exhaustion following so rapidly, that any previous ex- citement is scarcely to be perceived. Narcotics, there- fore, so far as we can speculate with any probability on their action, may be regarded as general diffusible sti- mulants. The hypothesis may also, however, be maintained perhaps, that along with their stimulating operation, they directly exhaust the powers of life; and that these two modes of action are not strictly proportional, but are different in different narcotics. The effects of cer- tain chemical agents on the system, as of nitrous oxide, and carburetted hydrogen, favour an hypothesis of this kind; the one producing high excitement without any proportional depression, the other producing exhaustion of power without any previous increased action. The truth, however, is, that from our imperfect knowledge of the laws of the living system, all such speculations are deficient in precision; nor can we do more than state the most general analogies, without attempting to extend them to any more minute applications. Thus, NARCOTICS. 109 in all the theories which have been advanced with re- gard to the operation of narcotics, the principles have been inferred from the action of a few of the most powerful,—alkohol or opium. They are after all, im- perfectly adapted to these, and are still more deficient when considered in relation to the others. As narcotics are capable of being administered, so as to obtain from their action either stimulant or sedative effects, it is obvious, that they may be employed as reme- dies, with the view of producing either of these. The exciting operation, however, is in general so transient, that few of them can be administered with advantage as stimulants. When given with this intention, they are applied in small doses, frequently repeated, as thus the state of excitement is best sustained. More usually they are given with the view of obtaining that state of dimi- nished action and susceptibility to impression, which is obtained from their operation with more certainty and permanence; they are then given in larger doses at more distant intervals. As stimulants, they are employed in various forms of continued fever, remittent and inter- mittent fever, and numerous diseases of debility. As se- datives, they are still more extensively used to alleviate or remove spasmodic action, to allay pain and irritation, to induce sleep, and to restrain morbidly increased eva- cuations and secretions. 110 NARCOTICS. Alkohol. Ether. Camphor. PAPAVER SoMNIFERU?! Hyoscyamus Niger. Atropa Belladona. AcONITUM NAPELLUS. Conium Maculatum. Digitalis Purpurea. Nicotiana Tabacum. Lactuca Virosa. Datura Stramonium. Rhododendron Chrysanthum. Rhus Toxicodendron. Arnica Montana. Humulus Lupulus. Strychnos Nu Vomica. Prunus Lauro-Cerasus. Alkohol. Ardent Spirit. Spirit of Wine. By the process of vinous fermentation, a product is formed, which, combined in the fermented liquor, gives to it its peculiar properties—pungency, spiritous flavour, and intoxicating power. Being volatile, it can be obtained by the process of distillation, and in the diluted state in which it is at first procured forms the spiritous liquors of commerce. By repeated distillations, it is procured more pure and concentrated, and then forms what was named Pure Ardent Spirit, or Spirit of Wine, by the older chemists,—names for which that of Alkohol is substituted in modern chemical language. This sub- stance operates on the living system as a highly diffusi- NARCOTICS. Ill ble stimulant; in the state of spiritous and vinous liquors, it is employed for medicinal purposes; and in its pure form is an important pharmaceutic agent. Alkohol is formed during the process of fermentation; and from the changes which occur during that process, we endeavour to infer the theory of its formation. Sac- charine matter, in the state in which it exists in sweet vegetable juices, and fecula, which has been converted by malting into sugar, or even to a certain extent unmalted, are the substances chiefly susceptible of this process: the access of the air is not necessary to it; and the water of the fermenting liquor does not appear to suffer decom- position. The series of changes, whence the alkohol is formed, must arise therefore from the reaction of the elements of the saccharine matter, and the new combi- nations which are established. These elements are car- bon, hydrogen, and oxygen; during the fermentation, carbonic acid is formed and disengaged: this must be derived from the combination of portions of the oxygen and carbon of the saccharine matter, (or of the fecula, which is of similar composition); and the alkohol, which is the only other product of the process, may, under this point of view, be considered as a compound of the remaining elements; in other words, of the hydrogen of the sugar with its remaining carbon and oxygen. This is the theory of the vinous fermentation, and of the composition of alkohol inferred by Lavoisier, from ex- periments undertaken with the view of investigating this subject. More recent researches, however, have shown, that it is imperfect. Lavoisier had supposed that pure saccha- rine matter alone is capable of fermenting, and that the whole changes which occur during the process are changes in its composition. This is not, however, strictly true. To excite fermentation in a solution of pure sugar, a certain quantity of what is named Ferment, of which yeast is a variety, is necessary, and sweet vegetable juices suffer it only from naturally containing this fer- ment. Now the agency of this substance remains to be 112 NARCOTICS. explained, and this has not yet been done in a satisfac- tory manner. It appears to approach to gluten or albu- men in its nature, and in particular contains nitrogen in its composition. This nitrogen, it is shown by the experiments of Thenard, disappears during the fermen- tation, and he has supposed it to enter into the compo- sition of the alkohol, while a portion too of the carbon of the ferment combines with part of the oxygen of the sugar, and contributes to form the carbonic acid disen- gaged. The whole of this subject, however, requires to be farther elucidated. From the analysis of alkohol, it appears to be a com- pound of carbon, hydrogen, and oxygen; hence, in burn- ing, it affords merely water and carbonic acid, and the quantity of water produced exceeds even the alkohol in weight. Lavoisier inferred, that it consists of 28.5 of carbon, 7.8 of hydrogen, and 63.5 of water, without any conclusive proof, however, that this large quantity of water exists in it fully formed, and not in part at least in the state of its elements. Saussure, in decomposing alko- hol, by detonating the vapour of it with oxygen gas, or by passing it through an ignited tube, discovered a little nitrogen in its composition, and has given the following as the proportions of its elements: carbon 43.65, oxygen 57.85, hydrogen 14.94, nitrogen 3.52. But with regard to the results of this analysis, it still remains altogether uncertain, what proportions of oxygen and hydrogen exist in the composition of the alkohol as immediate principles, and what exist in it in the state of water. The process for obtaining alkohol, consists in submit- ting vinous or fermented liquors to distillation. It distils over with a quantity of water, and in this manner are formed the spiritous liquors of commerce, these deriving peculiar flavour from the substances from which the fermented liquor has been prepared. These spiritous liquors, by repeated distillations, afford alkohol in a more concentrated state, different substances being added to facilitate the concentration and rectification. The pro- cess belongs to the pharmaceutical part of the work. NARCOTICS. 113 Pure alkohol is colourless and transparent; its odour is fragrant, and its taste highly pungent: it is lighter than water, the difference being greater, as the alkohol is more pure and concentrated, and hence the specific gravity is the best test of its strength. As prepared by the usual processes, it is of the specific gravity .835, and it is of this strength that it is ordered in the Phar- macopoeias, as fit for pharmaceutical purposes. By care- ful rectification, however, it may be brought to .815, and even to 800; and even, when of this degree of con- centration, we have no method of discovering what quantity of water is contained in it: hence we do not know what constitutes real alkohol. When of the com- mon strength, it is so volatile, as to evaporate speedily at the common temperature of the atmosphere; it boils at 165° of Fahrenheit. It is highly inflammable, burning when in contact with the air, when its temperature is raised not much above 300°; the products of its com- bustion are water and carbonic acid. Alkohol exerts chemical affinities to a number of sub- stances. With water it combines in every proportion. It dissolves a number of saline substances, especially the pure alkalis, and several neutral salts. It likewise dis- solves sulphur and phosphorus; and it is the solvent of a number of the vegetable proximate principles, such as resin, camphor, essential oil, balsam, extract, and sac- charine matter. From this solvent power, alkohol is a very important pharmaceutic agent, particularly as applied to the vege- table articles of the Materia Medica; the principles which it dissolves being those in which medicinal pow- ers frequently reside, and being dissolved by it in such quantity as t© afford very active preparations. It has another important property, that of counteracting the spontaneous changes to which vegetables are liable from the reaction of their elements; and hence these solutions retain their properties unimpaired. When diluted with an equal weight of water, it still retains its solvent power to a certain extent, added to the solvent power Vol. I. P 114 NARCOTICS. of the water; and this diluted alkohol, as it is named, is even more generally employed in pharmacy as a solvent of vegetable matter, than alkohol in its pure form. Its specific gravity, when of the due strength, is .935. Alkohol is a powerful and highly diffusible stimulant. Taken in a moderate quantity, it almost immediately increases the force of the circulation, communicates a greater degree of muscular vigour, and excites exhilara- tion of mind: these gradually subside, and are followed by proportional languor. If the quantity is more consi-, derable, its exciting effects are more quickly produced, and are followed by intoxication, temporary delirium, and stupor; and in a large dose it occasions death, with scarcely any symptom of previous excitement. Its ana- logy in producing these effects to other narcotics is suf- ficiently obvious. Its exciting power, however, appears to be rather more permanent than that of some of the medicines of this class; and hence, while it can be suc- cessfully employed to rouse the powers of the system, it can scarcely be used with equal advantage to repress irregular action, diminish irritation, or induce sleep. Alkohol, in its pure state, can scarcely be said to be employed in medicine. Sometimes it is used as an ap- plication to burns, and to certain states of local inflam- mation not connected with increased action; it is applied by friction to the surface to relieve muscular pains; or to bleeding wounds to restrain haemorrhage. Spiritous liquors, which consist merely of diluted al- kohol, are employed as general stimulants to excite the actions of the system. Their stimulant operation, how- ever, is not sufficiently permanent or capable of being regulated, so as to avoid the injurious consequences they are liable to produce, to admit of their being em- ployed, except as occasional remedies. Wines and fermented liquors owe their- exhilarating power probably to the portion of alkohol they contain. The opinion has been advanced indeed, that the alkohol they afford by distillation does not pre-exist in them, but is formed during the distillation; this opinion rest- ing on the facts, that the alkohol cannot be procured NARCOTICS. 115 from them in the same quantity by any other method; and that when the product of the distillation is added to the residual liquor, wine is not reproduced. These facts are inconclusive; the similarity of power in vinous liquors to that of alkohol, affords perhaps sufficient reason to conclude, that it exists in them actually form- ed, though it may be disguised by combination with their other principles. The action of wine on the system, though analogous to that of alkohol, is not precisely alike; its stimulant operation appears to be less sudden and more durable; and hence it can be employed with more advantage as a tonic. It is as a tonic indeed, rather than as a narcotic, that wine is administered. Its chief medicinal applica- tion is in the treatment of fevers of the typhoid type, in which it is employed to support the strength of the sys- tern, and to obviate symptoms arising from debility. With these views, it is given with more advantage than any other tonic,—a superiority derived from its stimu- lating power being obtained with more certainty, and being more easily regulated, from its being more grate- ful, and probably not requiring to be assimilated by the digestive organs to produce its effects. The quantity in which it is given is altogether dependent on the state of disease; the object to be attained is that of supporting the strength of the system until the disease has run its course; the danger to be avoided is that of giving it so largely, as to occasion any degree of exhaustion. Its administration is regulated, therefore, by the effects it produces; advantage being always derived from it, when it renders the pulse more slow and firm; when the re- currence of delirium is prevented; when irritation is les- sened, and sleep induced. If the pulse is quickened, and the countenance becomes flushed; if it excite thirst, in- crease the heat of the body, and occasion restlessness or delirium, it is obviously injurious; and the dose must either be diminished, or its use altogether suspended. In general its opeiation is less powerful than it is on the system in a state of health; larger quantities therefore 116 NARCOTICS. can be taken, and are even required to produce any ex- citing effect. In various diseases of chronic weakness, or where the strength of the system has been reduced by profuse eva- cuations, or by any other debilitating operation, wine is in common use as a cordial and tonic. Different wines have effects somewhat different, ac- cording as they are possessed of astringency, or as they are sweet or acescent; and are hence adapted to answer different indications. The wines prepared from other fruits than the grape, are less spiritous and more acescent, and are hence in- ferior in tonic power. Fermented liquors, especially porter, are sometimes substituted for wine, where this is necessary from idiosyncracy, and their powers are some- what modified by their other qualities, particularly by their bitterness, and by the pungency arising from their excess of carbonic acid. Their narcotic power too is often greater than is proportioned to their vinous strength, owing to the addition of narcotic substances which they often receive in their preparation. From the immoderate and long continued use of vinous and spiritous liquors, many diseases derive their origin; as dyspepsia, hypochondriasis, visceral obstruc- tions, chronic inflammation of the liver, and gout,-— morbid states probably arising either from the increased action it excites, giving rise to organic derangements, or from the exhaustion of power, general or local, pro- duced by stimulant operation unnecessarily excited or too long continued. Ether Sulphuricus. Sulphuric Ether. Alkohol suffers decomposition from the action of the more powerful acids upon it; and substances are formed by these decompositions which have a resem- blance in their general properties, though, as produced by the action of the different acids, they have also pecu- liar powers. They are denominated Ethers. Sulphuric NARCOTICS. 117 ether, formed by the action of sulphuric acid on alkohol, is the one that has been chiefly applied to any medicinal purpose; and its powers are those of a narcotic. Nitric ether, in the state in which it has been used, dilute, and with a portion of free acid, acts principally as a diu- retic, and is therefore placed under that class. The other ethers are of more difficult preparation, and have scarcely been introduced into the Materia Medica. Sulphuric ether is obtained by exposing a mixture of sulphuric acid and alkohol, in equal weights, to a heat sufficient to produce ebullition; it distils over, and is purified by a second distillation, any free acid being ab- stracted by an alkali. The process is considered more fully in the pharmaceutical part of the work. A diluted preparation is ordered in the pharmacopoeias, in which the rectified ether is mixed with two parts of alkohol; and in the London Pharmacopoeia there is another pre- paration, in which a product that is obtained at the end of the distillation, of an oily appearance, ethereal oil, is added to this diluted ether; neither of these preparations is of any importance. Sulphuric ether is colourless and transparent, highly odorous and pungent, and of a specific gravity inferior even to that of alkohol, being, when it is rectified, not more than .730, compared with the standard specific gravity of water. It is very volatile, evaporating speedily at natural temperatures; and from its rapid transition to vapour, producing much cold during its evaporation. In vacuo it boils below the freezing point of water, and under the atmospheric pressure it boils at 98. It is also highly inflammable, and affords by its combustion water and carbonic acid. It differs from alkohol, principally in containing a larger proportion of hydrogen, and to this its greater levity and volatility are probably owing. The proportions of its elements, as assigned by Saussure, are carbon 59, oxygen 19, hydrogen 22. Sulphuric ether is a powerful diffusible stimulant, somewhat analogous to alkohol in its action^ and, like it, capable of producing intoxication. Its stimulant ope- 118 NARCOTICS. ration appeafs to be even more suddenly exerted, and to be less durable: hence its superiority as a narcotic and antispasmodic. As a stimulant, it is sometimes given in occasional doses in typhus fever, more particularly in those cases where symptoms are present, connected with spasmodic action; it is also given in other forms of fever to obviate nausea; and it is said to be useful in abating the violence of sea sickness. As an antispasmodic, it is employed in spasmodic asthma, and sometimes affords sudden and complete relief, producing for a time at least remission of the paroxysm: it is also given with advan- tage in the hysteric paroxysm; it is one of the most powerful remedies in cramp of the stomach, and singul- tus; and it sometimes relieves some of the symptoms of cholera, especially the vomiting. Its usual dose is a tea- spoonful, equal to about a drachm; but its beneficial effects are frequently not obtained, unless it be given in a larger dose, or until the dose has been repeated at short intervals. In dyspnoea and catarrh, its vapour inhaled into the lungs affords relief, probably from its antispas- modic power. Externally applied, it relieves muscular pains; it is an excellent application to burns; and from the degree of cold which attends its evaporation, it has been employed to favour the reduction of strangulated hernia, being dropt on the tumour, and allowed to eva- porate freely. Camphora. Camphor. Laurus Camphora, Lin. CI. Enneandria. Ord. Monogynia. Nat. Ord. Oleraceee. Habitat, Japan, India. Camphor is not the produce exclusively of one ve- getable, but is contained in many plants, especially those of the aromatic kind, diffused through their wood or bark, and is often deposited from their essential oils when these are long kept. The oils of peppermint, thyme, sage, and a number of others, thus afford it. For the purposes of commerce, it is obtained from a species of laurel, the Laurus Camphora, a native of Japan. It exists in distinct grains in the wood of the root and branches NARCOTICS. lift of this tree. It is extracted by sublimation, the wood being exposed to heat with a quantity of water, and the temperature thus communicated being sufficient to vo- latilize the camphor; in Europe, it is purified by a second sublimation, with the addition of one-twentieth of its weight of lime. Pure camphor is colourless, semi-transparent, tena- cious, and somewhat unctuous to the touch; its smell is strong and fragrant; its taste is pungent and bitter. It is volatile at every natural temperature, and soon dimi- nishes in bulk from exposure to the air; it melts at a heat inferior to 212°; is highly inflammable; it is scarcely soluble in water, but entirely soluble in alkohol, ether, and oils essential or expressed. The alkalis do not act upon it. The acids dissolve it, and the more powerful acids decompose it. These properties are sufficient to distinguish it from the other proximate principles of vegetables. It approaches nearest in its characters to essential oil, and appears to differ from oil in chemical composition, principally in containing a larger propor- tion of carbon. Hence, when its volatilization is pre- vented, and it is subjected to a temperature so high as to decompose it, as may be done by exposing it in mixture with pure clay to a heat suddenly raised, it affords a liquid, having all the properties of an essential oil, odorous and pungent. There remains a considera- ble proportion of charcoal; carbonic acid, and carbu- retted hydrogen gases are disengaged, and an acid liquid is obtained, named camphoric acid. This acid, which is also formed from camphor by combustion, and by the action of nitric acid, has some resemblance to benzoic acid. In a moderate dose, camphor produces effects similar to those of other narcotics, exciting first the actions of the system. This stimulant operation, however, is not considerable, even in a small dose; and in a large dose it diminishes the force of the circulation, induces leep, and sometimes causes delirium, vertigo, convulsions, or coma. 120 NARCOTICS. As a stimulant, camphor has been used in typhus, cynanche maligna, confluent small-pox, and other febrile affections accompanied with debility; in retrocedent gout, and to check the progress of gangrene; but its stimulant operation is scarcely sufficiently permanent to admit of being easily regulated. As a sedative, it is used in affections of an opposite nature, as in pneumonia, rheumatism, and gonorrhoea, combined with nitre or an- timonials, or by itself, where evacuations have been previously employed. In mania, it has sometimes suc- ceeded as an anodyne: as an antispasmodic, it has been employed in asthma, chorea, and epilepsy. The dose of camphor is from 5 to 20 grains, but it is seldom that it is given at once in so large a dose as the latter quantity, from being liable to produce nausea and irritation. In small doses, on the other hand, it produces little effect, unless these are frequently repeated. In di- vided doses, it may be given to the extent of a drachm or more in the day. Its power of checking the progress of gangrene has been supposed to be promoted by com- bination with musk, or carbonate of ammonia: com- bined with opium, it forms a powerful diaphoretic; and its efficacy in inflammatory diseases is augmented by an- timonials. Camphor ought generally to be given in a state of mixture in some liquid form, as in the solid state it is very apt to excite nausea. It may be diffused in water by trituration with sugar, mucilage, or almonds. The camphorated mixture of the London Pharmacopoeia, in which camphor is triturated with water, and strained, is a preparation which from the small quantity water can dissolve, can have scarcely any power. In the pharma- ceutic treatment of camphor, it is necessary, in order to reduce it to powder, to add a few drops of alkohol during the trituration. Magnesia, by being triturated with it, has the effect of dividing and rendering it smooth, and may be used for its suspension; a number of the gum-resins also act on it in such a manner, that from their mixture a soft uniform mass is formed, and this NARCOTICS. 121 affords another mode of diffusing it in water. From this chemical action, it cannot well be combined with gum-resins in the solid form.* Externally applied, camphor is used as an anodyne in rheumatism and muscular pains, and as a discutient in bruises and inflammatory affections; it is dissolved in al- kohol or expressed oil, and applied by friction to the part. Added to collyria, or mixed with lard, it is of advantage in ophthalmia. Suspended in oil, it is used as an injection in ardor urinae, and as an enema to relieve the uneasy sensations occasioned by ascarides. The combination of it with opium is useful as a local appli- cation in toothach. Offic. Prep.—Acid. Acetos. Camph. Emuls. Camph. Ol. Camph. Tinct. Camph. Ph. Ed.—Mist. Camph. Lin. Camph. Lin. Camph. Comp. Tinct. Camph. Comp. Ph. Lond.\ Pap aver somniferum. White Poppy. Pohjand. Monogyn. Rhcead. Capsula et Succus sphsut. Europe, Asia. Th e White Poppy is a native of the warmer regions of Europe and Asia; it also grows in colder climates, and without any diminution of its powers. The large capsule which it bears, affords, by incision in its cor- tical part, a milky juice, which by exposure to the sun and air, becomes concrete, and of a brown colour. This is named Opium, and is the production of the plant that is chiefly medicinally employed. The leaves and stalks afford by expression a juice inferior in narcotic power; the seeds are inert. The opium of commerce is in flat or rounded masses, which when cut present a substance soft and tenacious, * By trituration, Camphor is very soluble in milk, and in this mode it is most conveniently exhibited.—Ed t In annexing a list of the officinal preparations of each article to its history, I place first those of the Edinburgh Pharmacopoeia, and without extending it unnecessarily, by inserting the names of the corresponding preparations of the London and Dublin Pharma- copoeias, I merely add those which are peculiar to either of the latter. Vol. I. Q 122 NARCOTICS. of a dark reddish brown colour, having a strong odour, somewhat foetid, and a taste bitter and acrid. These are the properties of what is named Turkey opium. A kind of inferior quality is known in the shops by the name of East India Opium, which is softer, of a blackish colour, and has a fainter smell. Though opium has been often submitted to analysis, its proximate principles are still imperfectly determined. It is highly inflammable; submitted to the action of alko- hol, a considerable portion of it is dissolved; and water likewise dissolves it in part. The solution in alkohol is much more highly impregnated than that in water; and it possesses, in a much higher degree, the narcotic pow- er. Diluted alkohol, composed of equal parts of alkohol and water, appears to dissolve all its active matter; the tincture prepared by this menstruum, when the due pro- portion of solvent is employed, being equal, or very near- ly so, in power to the quantity of opium submitted to its action. After the joint action of alkohol and water on opium, there remains, mixed with the accidental impu- rities, a substance plastic and glutinous, the nature of which has not been ascertained; Bucholz considering it as similar to caoutchouc, and Gren supposing it analo- gous to gluten; it retains no activity. By boiling in water under exposure to the air, the narcotic power of opium is impaired; this can scarcely be ascribed, how- ever, to the dissipation of any active volatile principle; for when water is distilled from it, and condensed, it is found to have scarcely any narcotic power: it must therefore be owing to changes produced at this tem- perature in the principles in which the activity of the opium resides. From these facts it is not easy to draw any precise conclusion with regard to the nature of the active matter of opium. As it is partly soluble both in water and in alkohol, and appears to suffer decomposition when boiled in water under exposure to the air, it might be concluded to be of the nature of extractive matter. On the contrary, being inflammable, and much more soluble in alkohol NARCOTICS. 123 than in water, it approaches more in its characters to resin; yet it is not purely resinous, for its solution in pure alkohol is but slightly decomposed by water. The analysis of opium, in common with that of many of the other articles of the Materia Medica, affords sufficient proof of our very imperfect knowledge of the constituent proximate principles of vegetable matter. It has lately been stated by Derosne, that a peculiar principle resides in opium on which its narcotic quality depends. It is obtained by digesting water on opium, and evaporating the solution; a matter which precipitates during the evaporation, and which consists of this prin- ciple with a portion of resin and extract, is to be digested with alkohol; the resin and this principle are dissolved; and as the solution cools, the latter separates in crystalline grains, which may be purified by solution and crystalli- zation; it is described as being in prisms, white, insipid, and inodorous: insoluble in cold water, very sparingly - soluble in hot water, but dissolved by alkohol, ether, and by the acids and alkalis; and possessed of narcotic power. These experiments present results so little analo- gous to those of former researches on the principles of opium, that they require confirmation; nor, were they confirmed, can this be properly regarded as the narcotic principle of opium, since its power, though it exists in small proportion only to the other principles, does not appear to have much exceeded that of opium itself. The facts ascertained with regard to the action of the usual re-agents upon opium, are of importance, as point- ing out its proper pharmaceutic treatment. Diluted al- kohol dissolving all its active matter, is the menstruum best adapted to its preparation under the form of tinc- ture. Water dissolving it less perfectly, can scarcely be employed with advantage. Vinegar dissolves its active matter, but has been found to impair much its narcotic power, probably by causing in it some chemical change. Wine, though it dissolves sufficiently its active princi- ples, being liable to pass to the state of vinegar, is an improper menstruum. Any purification of opium, by 124 NARCOTICS. dissolving it, and evaporating the solution, only weakens its strength, and renders it uncertain; and hence this process formerly employed is now discarded from the Pharmacopoeias; or at least is only retained in that of the Dublin College. With regard to the nature of the action of opium on the living system, very different opinions have been maintained. The effects it produces appear sufficiently to establish the conclusion, that it is a powerful and highly diffusible stimulant. In a moderate dose, it in- creases immediately the frequency, force, and fulness of the pulse; augments the animal temperature, and gives vigour to every function of the body and mind, occasioning often intoxication and delirium. These are succeeded by diminution of the force and frequency of the pulse, by lassitude, impaired sensibility and sleep; and these again are frequently followed by sickness, headach, thirst, tremors, and other symptoms of debi- lity. The primary operation is therefore evidently exci- ting; and the state of diminished susceptibility and action which follows, must be considered as the effect of this, conformable to the general law, that excitement suddenly raised is followed by exhaustion of power. If a larger dose of opium be given, the symptoms of diminished action appear without any previous excite- ment, and are followed by delirium, stupor, deep and difficult breathing, convulsions and death. In this too the analogy of opium to other diffusible stimulants is sufficiently strict. From its topical application, similar effects are pro- duced: at first, increase of pain, augmented muscular contraction, increased heat, and even inflammation, which are more or less quickly succeeded by a greater insensibility to impressions, and a greater difficulty of being excited to contraction by the application of other stimuli. The latter symptoms are also immediately in- duced by the application of a large quantity to the mus- cular fibre. The action of opium on the system in a diseased state NARCOTICS. 125 is precisely analogous. In typhus and other diseases of debility, its exhibition in a moderate dose produces all the salutary effects resulting from the administration of wine and other powerful stimulants, while in diseases of an opposite nature, where there is already increased action, it is not less prejudicial. It is to be admitted, however, with regard to opium, that its apparent sedative effects, displayed in its lessen- ing the sensibility to external impressions, diminishing action, and inducing sleep, are greater than are propor- tional to the previous excitement it raises, or to an equal or greater excitement produced by other stimulants, as by alkohol. This has been accounted for from the greater diffusibility, and less durability of its primary operation; in consequence of which, the excitement it produces is soon extended over the system, and is more quickly suc- ceeded by the secondary state of diminished power. Whether this theory of its action be satisfactory or not, and whether it be regarded as a powerful stimulant, or as a direct sedative, it is to be observed, and the obser- vation extends to analogous narcotics, that the practical application of it is nearly the same; since it is admitted that it may be exhibited so as to obtain from it stimu- lant and also depressing effects, and that the former are primary, and are obtained from it in a moderate dose, while the latter are secondary, and are only produced by a larger dose. Although, therefore, the explanation of the mode of operation be different, there is no dispute as to the operation itself, or the effects it produces. Opium was at one time supposed to act on the sys- tem, by the medium of the blood; but experiments have sufficiently shown, that its general effects are produced when the circulation is entirely interrupted, that its ac- tion is on the living solids, and is propagated to distant parts by nervous communication. The principal indications which opium is capable of fulfilling, are, supporting the actions of the system, allaying pain and irritation, relieving spasmodic action, inducing sleep, and checking morbidly increased evacu- 126 NARCOTICS. ations. It is differently administered, as it is designed to fulfil one or other of these indications. When given with the view of obtaining its stimulant operation, it ought to be administered in small doses, frequently repeated, and slowly increased, as by this mode the excitement it produces is best kept up. But where the design is to mitigate pain or irritation, or the symptoms arising from these, it ought to be given in a full dose, and at distant intervals, by which the state of diminished power and sensibility is most completely induced. One other general rule with respect to the adminis- tration of opium, is, that it ought not to be given in any pure inflammatory affection, at least unless evacuations • have been used, or unless means are employed to deter- mine it to the surface, and produce diaphoresis. In continued fever, not inflammatory, opium is admi- nistered sometimes as a general stimulant; but its ope- ration being less permanent than that of wine, it is not so well adapted to obviate debility; or at least with this intention it is employed only as subsidiary to wine. It is more frequently used to diminish irritation, and lessen that state of increased susceptibility to impressions con- nected with debility, which frequently gives rise to rest- lessness, watchfulness, delirium, and spasmodic affec- tions, particularly tremors, and subsultus tendinum. A full dose is usually given at bed-time; and to obviate these symptoms when they are urgent, it is farther occa- sionally administered, generally in combination with wine, in the course of the day. Its exhibition is impro- per, or requires to be conducted with much caution, where there is any tendency to local inflammation, or to determination to the head. If it increase delirium, it is obviously injurious. In intermittent fever, the administration of an opiate, previous to the expected approach of the paroxysm, ren- ders it milder, or sometimes even prevents its attack; given even during the hot stage, it lessens its violence; and administered in either mode, it facilitates the cure i NARCOTICS. 127 by other remedies, the stimulant operation of which is less transient.* In the phlegmasia?, the employment of opium is from its stimulant operation more doubtful, and in any pure inflammatory affection, attended with highly increased vascular action, must be hazardous. Where it is given so as to determine its action to the surface of the body, and produce sweat, it is often advantageously employed, particularly in rheumatism; or in some of the other dis- eases of this order, where the inflammatory stage has sub- sided, its exhibition is occasionally necessary to obviate symptoms connected with irritation. In the exanthemata, opium is employed with similar intentions, and is often more peculiarly advantageous, by lessening the irritation connected with the eruption. In small pox, it is peculiarly useful with this intention after the eruption is completed where it is copious; and if the concomitant fever be of the typhoid type, the same advantage is derived from it as in pure typhus. In measles, the state of the system being more purely inflammatory, its use is rather contra-indicated. In haemorrhagies, not connected with a state of highly increased vascular action, opium is a valuable remedy, by removing that state of increased irritability whence the discharge frequently arises; it is thus employed more particularly in passive menorrhagia, and in the haemor- rhage which sometimes succeeds abortion or delivery, f * Notwithstanding the use of opium in the hot stage of inter- mittent fever is sanctioned by the high authority of Di\ Lind, I am altogether opposed to the practice. My experience teaches me that it uniformly aggravates the paroxysm. As Dr. Lind practised chiefly in warm climates where there is an habitual tendency to perspiration, perhaps the salutary effect which he ascribes to the medicine may have happened. It is hard to discredit the observa- tions of so judicious a physician. If I were to repeat my trials with the opium, in this case, it should be in combination with antimo- ny or ipecacuanha, in the shape of Dover's powder, which might probably induce a state of relaxation of the surface of the body favourable to the prompt solution of the paroxysm—Ed. t Large doses of opium in uterine haemorrhage have recently been recommended by several distinguished writers. I have never 128 NARCOTICS. In the greater number of the profluvia, opium is cm- ployed with the same intention, and is the remedy in several of these diseases principally relied on. In dysen- tery, the propriety of its administration is more doubtful, or at least it can be given with advantage only in such doses as to relieve the pain and irritation which prevail; care being taken to obviate the constipation it might produce, by the exhibition of mild purgatives. In spasmodic and convulsive diseases, opium is ob- viously indicated, and in many of them is the remedy of greatest power. In chorea, it has been advantageous^ employed; though the dependence of this disease, on the accumulation of feculent matter in the intestines,. as established by Dr. Hamilton's observations, suggests the necessity of its being employed with caution, and of its constipating effect being carefully guarded agains^. In epilepsy, it sometimes abates the violence of the paroxysm, especially where this is liable to recur during sleep. In tetanus, to produce any relief, it requires to be given in very large doses, and these must be frequently repeated; and even then the system is often little affect- ed by it: when pushed, however, to a great extent, the violence of the spasmodic affection has at length been overcome, and a cure obtained. A similar remark ap- plies to hydrophobia, in which very large quantities of opium have been given without any sensible effect on the state of the functions, but in some cases with ulti- mate success. In mania, the system is in general little susceptible to the action of any medicine; but opium, when given in sufficient doses, is frequently useful in diminishing irritation,m and producing composure or sleep. In other cases it altogether fails, when given even in a very large dose, and sometimes even aggravates the restlessness and agitation of the patient. In the hys- exactly imitated this practice, but have often derived the greatest advantage in these cases from a union of opium and ipecacuanha in the proportion of a grain of the former to two grains of the lat- ter, to be repeated, more or less frequently, as the circumstances of the case may require.—Ed. NARCOTICS. 12© teric paroxysm, opium is often employed with advan- tage, either introduced into the stomach, or given under the form of enema. In purely spasmodic asthma, the paroxysm is shortened, and even sometimes cut short by a full dose of an opiate. In colic, it relieves the vio- lence of the pain; though its administration requires caution, where there is any tendency to an inflamma- tory state; and the constipation it is liable to produce requires also to be obviated. In cholera it is the principal remedy. In pyrosis, a moderate dose generally affords at least temporary relief; and it also frequently succeeds in checking vomiting from morbid irritability of the stomach. In syphilis, opium is employed, principally with the intention of alleviating the irritation arising from the operation of mercury; for there is no sufficient evidence for the opinion, which has been advanced with regard to the anti-syphilitic power of opium alone. Considera- ble advantage is derived from its use in extensive vene- real ulceration; as well as in the treatment of painful and irritable ulcers, not connected with a venereal taint. It is given too as a stimulant to check the progress of gangrene. In many other cases of morbid affection, opium is had recourse to merely to lessen irritation, relieve pain, or induce sleep. As a palliative, it is indeed the most valu- able article of the Materia Medica. Externally applied, opium alleviates pain and spas' modic action. Applied by friction, it thus relieves the pain of cramp,' and even of tetanus; and rubbed over the abdomen, it alleviates spasmodic pain of the stomach and intestines. It often relieves the pain of toothach. Applied under the form of enema, it is of singular effi- cacy in relieving tenesmus, and that painful affection of the prostate gland which is sometimes the consequence of the discharge in gonorrhoea having been suddenly checked; and also that irritable state of the neck of the bladder, which renders the discharge of urine pain- Vol. I. R 130 NARCOTICS. ful. It is used under the same form in diseases where it cannot be introduced into the stomach. The dose of this narcotic is very various, according to the state of disease, and the intention with which it is administered. One grain is the medium quantity to a person unaccustomed to its use. Its power on the sys- tem soon becomes weaker; and from habitual use is so much impaired, that very large doses are required to produce its usual effects. In some diseases, too, parti- cularly mania, tetanus and hydrophobia, it produces little sensible effect unless the dose be very large. In the last disease, it has been taken to the extent of two drachms in twelve hours, without abating the violence of the symptoms. Lastly, the operation of opium is much varied by idiosyncracy, the same dose producing very different effects on different individuals.* By the immoderate or long continued use of opium, the vigour of the digestive organs is impaired; hence loss of appetite, wasting of the body, and muscular weakness; the nervous system, and even the functions of the mind, are also affected; the patient is distressed with uneasy sensations, which are only imperfectly re- lieved by other stimulants, if opium is withheld, and at length fatuity and stupor are induced. When such a dose of opium is taken, as would prove fatal if its effects were not obviated, the symptoms are, in- sensibility, so 'hat the patient cannot be roused by any exertion; a pmse usually slow and full; deep and diffi- cult breathing, and the countenance generally somewhat flushed; this state of stupor continues sometimes with * The quantity of laudanum which has sometimes been taken would be incredible, if the fact were not attested by indisputable authority. I knew in one case, a wine glass-full of it to be given, several times in the twenty-four hours, for many months in suc- cession, to alleviate the pain from the passage of biliary calculi. In a case of cancer of the uterus which was under the care of two highly respectable physicians of this city, Drs. Monges and La Roche, the quantity was gradually increased to three pints of laudanum, besides a considerable portion of opium, in the twenty- four hours.—Ed. NARCOTICS. 131 occasional convulsions, until it terminate in death. The principal remedy in such a case is the immediate exhi- bition of an emetic, which requires to be of the most powerful kind. Sulphate of zinc, or sulphate of copper, is generally used, dissolved in water, and introduced by a flexible tube into the stomach, the former in the dose of one scruple, the latter in a dose from five to ten grains; and if vomiting is not soon induced, the dose is repeated. Along with this is employed free dilution with the ve- getable acids; as vinegar, which is to be swallowed in as large draughts as the stomach can receive it. The powers of the stomach and of the general system may be roused and sustained by small doses of warm brandy; coffee has been said to have been taken with advantage, and the patient ought to be kept awake, and, if possi- ble, in a state of gentle motion, at least for some hours.* Opium is used either solid, or under the form of tinc- ture, twenty five drops of the tincture being equal to one grain of crude opium. It is employed in the solid state when we wish it to act slowly, or on the stomach and intestinal canal, otherwise it is more convenient in the liquid form. There are, besides, various prepara- tions, in which it is either the principal ingredient, or modifies the power of others. Officinal Preparations.—Elect. Opiat. Pil. Opiat. Pulv. Opiat. Pulv. Ipecac, cum opio. Tinctura Opii. Tinct. Opii Ammoniatae. Tinct. Saponis cum opio. Troch. Glycirrhiz. cum opio, Pkarm. Ed.—Pil. Opii cum Sapon. Pulv. Cornu Usti cum opio. Tinct. Opii Camph. Vin. Opii. Emplast. Opii. Pharm. Lond.— Opium Purification. Extr. Opii. Syrup. Opii. Dub.\ * In these cases, after a short time, the pulse becomes full and febrile, accompanied by a phrenetic state of the brain. At this stage, copious blood-letting is most imperiously demanded.—Ed. t To the above preparations may be added two others, which, under the denomination of the Black Drop, are much used in the popular practice, and have acquired some reputation among the physicians of this city. Of my own knowledge, I can say little of this medicine. I have occasionally prescribed it, and I am inclined to believe not with- 132 NARCOTICS. The dried capsule of the poppy is sometimes em. ployed for medicinal purposes. Its active matter is ex- tracted by decoction with water; this evaporated, affords an extract similar in power to- opium, but weaker, or made into a syrup, by boiling with sugar, it is used as an anodyne. This syrup is a weak preparation, and is in general only given to children. One ounce of it is sup. posed to be equal to one grain of opium, but it is liable to be variable in strength. The dose to a child a year old is one drachm. A syrup made from opium has been supposed to be preferable, as the dose can be regulated with much more certainty, and a formula of this kind is accordingly adopted by the Dublin College; being prepared by dissolving the watery extract of opium, and forming this into a syrup, by adding the due pro- portion of sugar. An infusion of the capsules is used as an anodyne fomentation. Qffic. Prep.—Extr. Papav. alb. Syr. Papav. somnif. Ed.—Decoct. Papav. Somn. Lond. out advantage, in cases to which laudanum did not seem to be well suited. It is however alleged by those whose experience with it is more enlarged, that it is never productive of head-ach, giddiness, nausea, and the rest of the distressing narcotic effects of opium and its ordinary preparations. The formulae are as follows: 1. Take of purified opium, five ounces. --------- pimento and cinnamon, two drachms. ---------saffron and orange peel, of each one drachm. --------- spirit of wine rectified, one pint. Digest a week and strain the liquor through flannel, to which is to be added sugar candy enough to make it pleasantly sweet. 2. Take of opium, four ounces. —■------- sharp vinegar or lemon juice, four pints. Digest three weeks, and then add saffron, cloves, nutmegs, and cinnamon, of each an ounce, coarsely powdered. Continue the di- gestion a week longer, strain through flannel, and evaporate the liquor reduced to the consistence of syrup. The dose of these preparations is about a half of that of lauda- num, and it is the latter of them which is chiefly employed in Philadelphia. Neither the one nor the other is a new medicine, as similar receipts are to be found in the old writers. Vid. « The Mysteries of Opium Revealed," the first edition of Quincey's Dispensatory, &c,-—Ed. NARCOTICS. 133 Hyoscvamus Niger. Black Henbane. Pentand. Monog. Solanacex. Her da, Semen. Indigenous. The leaves of this plant, when recent, have a slightly foetid smell, and a mucilaginous taste; when dried, they lose both taste and smell, and their narcotic power is in part impaired. The root possesses the same qualities as the leaves, and even in a more eminent degree, but is liable to be more variable in strength. The seeds also are narcotic. Henbane has an analogy to opium in its action more than any other narcotic, particularly in the power of inducing sleep. In a moderate dose, it increases at first the strength of the pulse, and occasions some sense of heat, which are followed by diminished sensibility and motion; in some cases by thirst, sickness, stupor, and dimness of vision. In a large quantity, it occasions pro- found sleep, hard pulse, and sometimes delirium; and in a dose which proves fatal, its operation soon terminates in coma, with a remarkable dilatation of the pupil, dis- tortion of the countenance, a weak tremulous pulse, and eruption of petechias. On dissection, inflamed or gangrenous spots have been observed on the internal surface of the stomach, and the vessels on the mem- branes of the brain have appeared enlarged. Its baneful effects, like those of other vegetable narcotics, are best counteracted by a powerful emetic, and by drinking largely of the vegetable acids. Henbane is one of the narcotics which has been longest known to physicians, having been employed by the ancients for mitigating pain, and restraining haemor- rhage. Stork of Vienna introduced it, and several other vegetable narcotics, to the notice of modern practi- tioners. He employed it in various spasmodic and pain- ful diseases, as in epilepsy, hysteria, palpitation, headach, paralysis, mania and scirrhus. It was given in the form of the inspissated juice of the fresh leaves, the dose of which is from one to two grains, which requires to be gradually increased. At present, it is principally em- ployed as a substitute for opium, where the latter, from 134 NARCOTICS. idiosyncracy, occasions any disagreeable symptom. The henbane also is free from the constipating quality of the opium. A tincture of it has been introduced into the Pharmacopoeias, which affords a preparation probably more uniform in strength than the inspissated juice. Its dose is thirty drops.* Offic. Prep.—Succ. spiss. Hyosc. N. Tinct. Hyosc. N. Ed. Lond. Dub. Atropa Belladonna. Deadly Nightshade. Pentand. Monogyn. Solanacea. Folia. Indigenous. The leaves have scarcely any smell, and only a slight- ly nauseous, sub-acrid taste. The berries are sweetish. Both are narcotic, as is also the root, but the leaves are preferred for medicinal use, as being more uniform in strength. In a moderate dose, belladonna occasions a sense of warmth, followed by diaphoresis, and a dis- position to sleep, frequently with nausea and headach; in large dose, symptoms of intoxication, vertigo, sick- ness and thirst: the pulse becomes low and feeble, the pupils are dilated, vision is impaired, and these symp- toms terminate in convulsions, coma, or paralysis. On dissection, where it has proved fatal, the stomach and intestines have been found inflamed, or gangrenous, and the blood in a dissolved state. The remedies are an emetic in a sufficiently large dose, and dilution with the vegetable acids. Belladonna was first employed as an external applica- tion, in the form of fomentation, to scirrhus and cancer. It was afterwards administered internally in the same affections; and numerous cases in which it had proved successful, were given on the authority of the German practitioners. It has been recommended too, as a reme- dy in extensive ulceration, in paralysis, chronic rheuma- tism, epilepsy, mania, and hydrophobia, but with so * The henbane is one of those plants which is cultivated in several parts of this country for medicinal purposes, and succeeds well.—Ed. NARCOTICS. 135 little discrimination, that little reliance can be placed on the testimonies in its favour: and in modern practice, it is little employed. It appears to have a peculiar action on the eye; hence it has been used in amaurosis; and from its power of causing dilatation of the pupil, when topically applied under the form of infusion, it has been used before performing the operation for cata- ract,—a practice which is hazardous, as the pupil, though much dilated by the application, instantly con- tracts when the instrument is introduced.* When given internally, its dose is from one to three grains of the dried leaves, or one grain of the inspissated juice. Offic. Prep.—Succ. Spiss. Atrop. Bellad. Ed. Lond. Aconitum Napellus. Aconite, Monk's-Hood, or Wolfsbane. Poly and. Trigyn. Multisiliqux. Herba. Europe, America. Th e smell of the leaves of aconite, when recent, is narcotic, but is lost by drying. Their taste is sub acrid. In a moderate dose its effects are those of a narcotic, accompanied with slight diaphoresis; in a larger dose it occasions vertigo, syncope, paralysis and convulsions. Aconite was employed by Stork in obstinate chronic rheumatism, exostosis, paralysis, ulceration and scirrhus. Though highly praised, it has fallen almost entirely into disuse. Its dose is from one to two grains of the dried leaves; of the inspissated juice half a grain, this dose being gradually increased. Offic. Prep.—Succ. Spiss. Aconit. Napell. Ed. Lond. Conium Maculatum. Cicuta. Hemlock. Pentand. Dfgyn. Um- bellate. Folia, Semen. Indigenous. This plant, which grows abundantly in this country in waste grounds, is of the umbelliferous kind. It is dis- tinguished from other similar vegetables by its large and spotted stalk, by the dark green colour of the lower leaves, and by its peculiar faint disagreeable smell, * This remark is not correct. There is not this tendency in the pupil to immediate contraction.—En. 136 NARCOTICS. which becomes more perceptible in the leaves when they are bruised. The seeds have a fainter odour, and are inferior in power. The root has similar powers, but varies in strength at different seasons. Hemlock is a very powerful narcotic. Even in a mo- derate dose it-is liable to produce sickness and vertigo; in a larger dose it occasions permanent sickness, with great anxiety, dimness of vision, delirium, convulsions and coma. The use of it was confined to external appli. tion, until it was introduced by Stork, principally as a remedy ^n scirrhus and cancer; and the beneficial effects obtained from it were in many cases so conspicuous, that sanguine expectations were formed of its efficacy; in cancerous ulceration in particular, the pain abates, and the discharge becomes less copious and acrid under its use, and the ulcer frequently contracts in size, and shows a disposition to heal. These effects, however, are usually only temporary, or cannot be carried beyond a certain extent; and though many cases were related by Stork and others, of permanent cures having been ob- tained from it, there is much reason to believe that its efficacv was exaggerated. It is now regarded only as a palliative, but, considering it even as such, it is still a valuable remedy; it relieves the pain, and corrects the discharge even more effectually sometimes than opium, and it is not liable to occasion the disagreeable conse- quences which arise from that narcotic. And when opium is employed, hemlock is a valuable auxiliary, as it renders a smaller quantity necessary. Muchvbenefit is derived frequently from cicuta in other cases of extensive ulceration; particularly in those connected with a scrofulous taint; it promotes the ope- ration of mercury in healing venereal ulcers; and it is useful in removing glandular obstruction and indu- ration. Cicuta is given either under the form of the dried leaves, or of the juice of the fresh leaves inspissated by a gentle heat to the consistence of an extract, the former being given in a dose of two or three grains, the latter NARCOTICS. 137 in a dose of two grains. The dose of either requires to be increased, and that more quickly, and to a greater extent, than is the case with almost any other substance in the Materia Medica, so that at length it has been taken to the extent of a number of drachms in the course of the day. The inspissated juice is a preparation on the operation of which we can never depend; hence it is seldom used; and even the powder of the dried leaves is liable to be variable in strength. Its pharmaceutic treatment, therefore, is of much importance. The leaves ought to be collected when the flowers are about falling off: they ought to be dried before a gentle fire, be re- duced to powder as soon as they are dried, and kept in small phials, carefully secluded from the air and light. The proofs of their proper preparation, and of their ac- tivity, are the powder being of a lively green colour, and retaining the peculiar odour of the plant. The recent leaves are sometimes applied externally to painful or ill-conditioned ulcers, or a cataplasm for the same purpose may be formed from the dried powder mixed with crumbs of bread.* Offic. Prep.—Succus. Spiss. Conii Macul. Ph. Ed. Lond. Dub. * The cicuta is a medicine which I have very extensively em- ployed both in public and private practice, and I am entirely per- suaded, that its powers have been much less exaggerated by Stork, than is now generally supposed. As an active remedy, it has lost its reputation I suspect, from its being commonly found in the shops in a very inert state, and pe haps, still more from the small quantity in which it is exhibited. No article scarcely of the Materia Medica suffer more by keeping, or which requires, in order to attain its full effects, to have the dose so rapidly and largely increased. Being a medicine of uncertain operation, I generally begin its use with about four grains, three times a day, and cautiously en- large the dose till it powerfully acts upon the system. In many cases I have often given as much as half an ounce of the powaered leaves, or recent extract, in the course of the day. and sometimes nearly double this quantity. When thus boldly employed, much advantage may be expected from it in all the cases enumerated Vol. I. S 138 NARCOTICS. Digitalis Purpurea. Foxglove.Didynam. Angiosperm. Solanacc^ Folia. Indigenous. This indigenous plant grows on dry elevated situa- tions, and, from the beauty of its flowers, has often a place in our gardens. All its parts are powerfully nar- cotic, but the leaves being most uniform in strength, are preferred for medicinal use. They are large and oblong, of a green colour rather dark, have little smell, and a bitter somewhat acrid taste. They are collected when the plant is in blossom, and are dried before a gentle fire, the thicker stalks being removed; and they ought to be kept without being reduced to powder. The operation of digitalis on the system is extremely peculiar, and there is even considerable difficulty in as- certaining its real effects. In a full dose, it produces ex- haustion of power, marked by a great and sudden reduc- tion in the force of the circulation; the pulse being reduced both in frequency and force, falling sometimes from 70 to 40 or 35 beats in a minute, and being small and tremulous. This is accompanied with sickness, anxiety, vertigo, dimness of vision, and, in a large dose, with vomiting, syncope, coldness of the extremities, convulsions, and coma, with sometimes a fatal termina- tion. Yet these effects are not uniform, but even from the same dose we observe considerable diversity of ope- ration in different individuals: thus the pulse is some- times rendered lower, without being diminished in fulness; at other times it is rendered irregular: nor does sickness always accompany the reduction of the force of the circulation. Sometimes none of these effects, and scarcely any perceptible change in the state of the functions are immediately apparent; but if the dose be continued, they are suddenly produced. Effects are even observed from the operation of fox- above, and to which I may also add, the tic doloreux, and other ano- malous affections of the nerves. The cicuta is now cultivated in this section of the United States, and is vastly superior to that which is imported from abroad,—Ed. NARCOTICS. 139 glove, apparently of a very opposite kind. While it reduces the force of the circulation, it appears to in- crease the action of the absorbent system, and hence proves a powerful remedy in dropsy; and Dr. Wither- ing, by whom its powers were first particularly inves- tigated, observed, that when given in a state of disease, it was most successful, not where there existed increas- ed action in the system, but, on the contrary, in states of debility, where the pulse was feeble and intermitting, and the countenance pale. Other authors have remarked its stimulant operation; and Dr. Sanders, from a series of observations and experiments, has inferred, that it always acts primarily as a stimulant, augmenting, when given in a dose not too large, the force and frequency of the pulse, and inducing a state of increased action; it is only when it is accumulated by repetition, or by too large a dose, that reduction of the force of the circula- tion and other symptoms of diminished power are pro- duced; and hence, according to this view, it is strictly analogous in its operation to other narcotics.* It must be admitted, however, that it is more difficult to regulate the administration of digitalis, so as to obtain its continued stimulant operation, than it is with regard to other stimulants; that there is a rapid transition to a state of diminished action, and that this is greater, and more permanent, compared with the primary stimulant effect, than in other stimulants even of the diffusible kind. Foxglove, producing very different effects according to the mode in which it is administered, or according to the state of the system, is employed as a remedy in dif- ferent diseases. Under the present class, those applica- tions are to be considered, which appear to be connected with its action as a narcotic. * Experiments made in this University show that the primary operation of digitalis is slightly to increase the force and velocity of the circulation, which effect however is exceedingly transient, and is succeeded by exactly an opposite state of the pulse. Vid. Dr. Moore's Inaug. Thesis, published in 1801.—-Ed. 140 NARCOTICS. On this, in part at least, has been supposed to depend the advantage derived from it as a remedy in phthisis pulmonalis. When given to that extent in which it re- duces the velocity and force of the circulation, it proves useful, by counteracting that state of increased action which prevails in the incipient stage of the disease; and by diminishing the rapidity of the circulation through the lungs, it may facilitate the removal of the local af- fection. In the more advanced stages, it may operate, it has been conceived, by promoting absorption, thus re- moving the tuberculous affection, or withdrawing the purulent matter, before it has been rendered acrid by the action of the air. Sanguine expectations have been form- ed of the advantages to be derived from it in the treat- ment of phthisis, many of the symptoms disappearing under its use, and the progress of the disease appearing to be arrested. The change of organic structure is, however, so considerable, at least in the advanced state of the disease, as scarcely to admit of a cure from the operation of any remedy; and the operation of foxglove is so much diversified, that perhaps the proper mode of administering it has not been precisely determined, so as to admit of all the advantage being received from it that might be derived: it is difficult, as Dr. W. Hamilton has remarked, to give it so as to reduce the force of the circulation, and continue this effect, without its induc- ing other consequences, which compel us to relinquish its use. Foxglove has been proposed as a remedy in pneu- monia, from its power ql reducing the force of the cir- culation when given in a sufficient dose, conjoined with blood-letting; and cases have been related of the success attending the practice, while some authors have con- demned it as hazardous, from the excitement it is liable to produce. On a similar principle, it has been proposed to be employed in croup. In active haemorrhage, it might be expected from the same operation, to be a remedy of much power,- and according to the observations of Ferriar and others, it NARCOTICS. 141 may be employed with signal advantage in epistaxis, haemoptysis, and menorrhagia, either alone or in com- bination with opium. In spasmodic asthma, the combination of it with opium has afforded much relief. In palpitation arising from intemperance, or from passions of the mind, and not connected with dyspepsia, the irregular action of the heart has been abated, and at length entirely removed by its operation. Foxglove is given in substance, or under the form of infusion, decoction, or tincture. The medium dose of the powder of the dried leaves is half a grain; the dose of the infusion, prepared according to the formula in the Edinburgh Pharmacopoeia, is half an ounce: that of the tincture is fifteen drops; these quantities being given twice a-day. The decoction is an improper form, as being variable in strength. The tincture is the form of preparation under which it has usually been given as a narcotic: the infusion that in which it has been employ- ed as a diuretic. Given in substance, there is supposed to be rather more risk of its effects accumulating from repetition of the dose, so as to induce the unpleasant symptoms which arise from an over dose. To obtain the full narcotic operation of foxglove, the dose given at first requires to be gradually increased, but this increase must be made with much caution, not only from the hazard attending an over dose, but from the circumstance that the action of the remedy is for a time not apparent; but if the dose has been too large, or repeated at intervals not sufficiently distant, it appears suddenly, and continues progressive. Hence the neces- sity of the practitioner's watching with the greatest attention the effects it produces.* The augmentation * This is a useful practical precept. More than once I have ob- served, especially in dropsical effusions, that though the digitalis was given for a succession of days, in an ample dose, it produced no sensible effect, influencing neither the arterial nor absorbent system, or any of the functions of the animal economy, when, sud- denly, there would come on an uncommon depression of pulse, and 142 NARCOTICS. may proceed at the rate of one fourth of the original quantity every second day, and the dose should not be repeated more than twice, or at farthest thrice a-day, unless in acute diseases, where the effect must be more speedily obtained, and where, therefore, the augmenta- tion must be more rapid. The increase is continued until the effect intended to be obtained from the remedy is produced, or until its operation is apparent on the system; and whenever the pulse begins to diminish in frequency or force, the increase of dose must be stopt; and if the reduction be considerable, or proceed rapidly, the administration of the remedy must be suspended, and, only after a sufficient interval, cautiously renewed. This is more especially necessary when nausea is in- duced, dimness of vision, vertigo, or any tendency to fainting. When these symptoms do occur, they are best obviated by small doses of stimulants, warm wine, or brandy and water, with aromatics, ether, and, as some have recommended, strong bitter infusions, small doses of opium, and a blister applied to the region of the stomach. The infusion of foxglove has been applied externally as an anodyne lotion to painful cutaneous eruptions, or ulceration. An ointment composed of the powder mix- ed with lard, has been found successful in obstinate tinea capitis. loss of general power, accompanied by the most copious urinary discharges. Another peculiarity in the operation of our medicine, which was first noticed in the Edinburgh Medical Journal, is worthy of atten- tion. I mean that its action, in some instances, is in no inconsidera- ble degi-ee regulated by the different positions of the patient's body. In the case alluded to, the pulse was not at all reduced in frequency when the patient stood up, being in this posture, up- wards of an hundred: when he sat down, it fell to seventy-five, and When lying on his back, to forty, in the minute. Cases of a similar nature, though not to the same extent, have since been recorded by Drs. Hamilton, Beddoes, and other respect- able writers, so as to leave no doubt of the occasional occurrence of this anomaly.—Ed. NARCOTICS. 145 The application of foxglove, as a diuretic, will be considered under the class of diuretics. Offic. Prep.—Infus. Digit. P. Tinct. Digit. P. Ed. Lond. Dub. Decoct. Digit. Dub. Nicotiana Tabacum. Tobacco. Pentand. Monogyn. Solanacex. Folia. America. This plant, though sometimes cultivated in this country, is usually imported from America. Its leaves, which are of a large size, are of a light green colour, which they retain with little change when merely dried;. but in the usual preparation to which they are subject- ed, they are rendered brown by the action of a little sulphate of iron. Their smell is foetid, their taste ex- tremely bitter and acrid. They deflagrate in burning, from a quantity of nitre they contain. Their active mat- ter is extracted both by water and by alkohol; by decoc- tion, their powers are much impaired. The essential oil obtained from them by distillation has been said to be very highly narcotic;—an assertion which has been denied, however, by some authors. Tobacco operates as a very powerful narcotic. This is apparent, even in the common practices of smoking and chewing it, though its effects, like those of other narco- tics, become less powerful from continued use. In a person unaccustomed to it, or in an over dose, it ex- cites the most severe and permanent sickness, with vomiting, reduces the force of the circulation, and occa- sions extreme muscular debility, with insensibility, cold sweats, and convulsions. Taken repeatedly in small doses, it acts as a diuretic, probably by promoting ab- sorption. As a diffusible stimulant, the smoke of tobacco, thrown into the rectum, was at one time employed in the recovery of drowned persons,—a practice unques- tionably hurtful, and now exploded. The same prac- tice is still occasionally employed in ileus and incarce- rated hernia; in the former disease, with the view of removing the constricted state of the intestines; in the 144 NARCOTICS. latter, with the intention of producing that state of mus- cular relaxation which may favour the reduction of the protruded intestine. The practice, though not without hazard, has sometimes proved successful. The watery infusion of the strength of one drachm of the dried leaves to a pound of tepid water, is a more convenient form of employing it than the smoke, as an enema; and even the infusion of this strength has sometimes pro- duced alarming symptoms of exhaustion. Unless it be used, however, in such a state of activity, as to produce some degree of muscular debility, no advantage can be derived from it; and the practice is therefore only to be had recourse to, where other methods have failed. The smoke of tobacco received into the mouth, relieves the pain of toothach, either by its narcotic power, or by exciting a profuse salivary discharge. The powder is in common use as an errhine. The infusion or decoction is sometimes used as an emetic, but its operation is extremely harsh, and accompanied with severe sickness. The medicated wine is the form under which it has been used as a diuretic, in dropsy and dysuria, its dose being 30 drops. The leaves bruised, or moistened, have been employed as a local application in tinea capitis, and in various cutaneous eruptions; incautiously ap- plied, they have sometimes occasioned the effects which arise from the internal administration of tobacco in too large a dose.* Offic. Prep.—Vm. Nicot. Tab. Ph. Ed.— Infus. Nicot. Tab. Lond.—Tinct. Nicot. Tab. Lond. * Applied to the region of the stomach, a cataplasm of the leaves of tobacco proves in some instances, very actively emetic, and is often in popular practice resorted to, where poisons have been swallowed. The same application is also sometimes made to expel worms, with what success, I cannot say. I have occasionally directed it in some cases of the more violent forms of mania, with a view of subduing the vigour and excitement of the patient, but I am not certain whether it has any superiority over the ordinary nauseating remedies.—Ed. NARCOTICS. 145 Lactuca Virosa. Strong-scented Lettuce. Syngenes. Polygam. equal. Composite. Folia. Indigenous. The leaves of this plant have a strong foetid smell, similar to opium, and yield a white juice, in which their activity resides. Their taste is bitter and acrid. Though narcotic, they have been used principally as a diuretic in dropsy, under the form of the expressed juice inspis- sated. The dose of this is five or ten grains, which is gradually increased to one or two drachms in twenty- four hours. By the German practitioners, by whom principally this plant has been recommended, it has also been used as a remedy in palpitation of the heart, and in intermittent fever. Offic. Prep.—Succ. Spiss. Lact. Vir. Ed. Datura Stramonium. Thorn-Apple. Pentand. Monog. Solana- cee. Herba. Indigenous. The leaves have a narcotic odour, and a bitter taste. They possess all the powers of a narcotic, producing, when taken in too large a quantity, vertigo, sickness, delirium, and convulsions. The usual form in which it has been given, is that of the inspissated expressed juice of the leaves, the dose of which is from one to three grains twice a-day, gradually increased.* * Doubts have been entertained by the botanists whether the stramonium is a native of the United States. Be this as it may, it now grows very abundantly in almost every section of the coun- try, and is known by the popular titles of Jameston weed, hen- bane, thorn-apple, stink-weed, &c. It is one of those plants which delight in a rich soil, and is most commonly to be met with on dung-hills, or other spots of great fertility. The stramonium, in its operation on the living system, is among the most powerful articles of the Materia Medica. In all its pro- perties, it is closely allied to the narcotic stimulants, and when largely taken, has produced tetanus, hydrophobia, and the wildest forms of mental derangement. Every part of the plant is active; but, the preparations employed as a medicine are an inspissated juice or extract, and the dried leaves and seed powdered. Of each of these the dose is two grains, twice a-day, to be increased till it amounts to ten, fifteen, or twenty grains. The Vol. I. T 146 NARCOTICS. Arnica Montana. Leopards-Bane. Syvgenes. Polygam. super/. Composite. Flore;, Radix. Germany. The flowers of this plant have a smell slightly foetid, and a penetrating bitter taste. In their action on the system, their direct stimulating power is very apparent The stramonium was originally introduced into the practice of physic by Dr. Siorck of Vienna, to whom we are indebted for our knowledge of the medicinal virtues of so many of the narcotic poisons, ft was used by him in mania, epilepsy, and in the spasmo- dic and convulsive affections generally. As is customary in the publication of a new remedy, he ascribed very valuable powers to this article, and was soon imitated in ,ts use by other practitioners, who confirmed by their testimony, the accuracy of his observa- tions. More diversified trials however, with the stramonium, gradu- ally diminished its reputation, till finally it ceased to attract any attention. In the late revival of the medicine by the American physicians, it has been very extensively applied to the treatment of diseases, and particularly in this city. It has been freely prescribed in epi- lepsy, chorea, tetanus, and with very equivocal results. More good has been done with it in some maniacal cases. I have sometimes found it to answer very well as a palliative in asthma, and perhaps still better, in the advanced stages of pulmonary consumption, where the cough is violent and the respiration exceedingly impe- ded. The manner of using it for these purposes, is to smoke the root previously washed, dried, and bruised, in a common tobacco- pipe. The stramonium, I am told, has been advantageously given in palsy and rheumatism. This I can readily believe; and also, that it will hereafter be discovered to be admirably adapted to a very large circle of cases Of the diseases in which I think it promises to be of the greatest service, are some of those of the eye, as amaurosis; and, as an emmenagogue, especially in dismenorrhcea. I have, in- deed, found it beneficial in painful menstruation. Exhibited alone, or in combination with mercury, it has like- wise proved in my hands a very valuable substitute for the cicuta in venereal and scrofulous ulcers of an ill condition. It corrects the state of the sore, and subdues the pain and irritability which are so frequently incident to these cases. As an external remedy the stramonium has not been neglected. The leaves steeped in brandy are recommended as an embroca- tion, and when boiled in milk certainly make a fomentation, which affords much relief in rheumatic and other painful swellings. There is an ointment formed of the stramonium which is of common use. It is prepared by boiling the bruised leaves of the NARCOTICS. 147 along with their narcotic action; they increase the force of the vascular system, and appear to communicate tone to the muscular fibre. In a larger dose, they produce vomiting and purging, sometimes followed by muscular pains, vertigo and convulsions. Along with narcotic effects, they excite vomiting and catharsis. They have been used in amaurosis, paralysis, convulsive disorders, gout, and rheumatism. The dose is five grains in sub- stance dried, or half a drachm in infusion. The root of arnica is aromatic and tonic, and has been used as a substitute for Peruvian bark. Rhododendron Chrysanthum. Yellow flowered Rhododendron. Decand. Monogyn. Bicornes. Folia. Siberia. The leaves of this plant are destitute of smell, but have a bitter, rough and subacrid taste, which they com- municate to water by infusion or decoction. They are stimulating and narcotic, and occasion in a small dose increased vascular action; in a large dose intoxication and delirium. They have been employed principally in chronic rheumatism and gout; their power is said to be marked by a sensation of creeping in the skin and dia- phoresis being induced. The form in which they have been given is decoction, 2 drachms being boiled in 10 ounces of water, and 1 or 2 ounces of the strained liquor being given twice a-day, and gradually increased. Rhus Toxicodendron. Poison Oak. Pentand. Trigyn. Dumoax. Folia. North America. This plant has so much acrimony, that the touching of the leaves, or rubbing them on the skin, occasions itching, inflammation, and desquamation; taken inter- nally, it excites nausea, vertigo, and pain in the head. plant in lard, and is employed in burns, in hemorrhoidal tumors, in psora, and in the herpetic eruptions. In each of these cases I have witnessed its good effects, and particularly in piles, attended with much sensibility and inflammation. For farther information on this subject vid. Cooper's Inaugural Thesis, printed in 1797.—Ed. 148 NARCOTICS. The dried leaves have been used in paralysis, in some cases related by Mr. Alderson with marked advantage. The dose given was half a grain twice or thrice a-day in the form of bolus, and gradually increased to three or four grains daily. It excites a sense of heat, and irre- gular motions in the parts affected. Humulus Lupulus. Hop. Dioecia. Pentand. Scabride. Indigenous. This plant is cultivated in England, being used in large quantity to give a degree of bitterness to fermented malt liquors. It is a very strong bitter, accompanied with a degree of aromatic flavour and some astringency; these are extracted by water by infusion; by decoction the aromatic flavour is lost. Along with its bitterness it has a narcotic power: of this the popular remedy, some- times successful, of a pillow of hops to procure sleep in the delirium of fever and in mania, is a proof. It ac- cordingly, when given internally in a full dose, reduces the frequency of the pulse and procures sleep. It has been employed as an anodyne, either in substance, in the dose of three grains, or under the form of infusion or tincture. A cataplasm or ointment prepared from it, has been also used as an anodyne application to cancerous sores. It has now a place in the London Pharmacopoeia. Off. Prep.—Tinct. Humul. Extr. Humul. Pharm. Lond. Strychnos Nux Vomica. Vomica Nut. Pentand. Monogyn. Solanacee. East Indies. The kernel of the fruit is the part of this plant that is powerfully narcotic; its taste is intensely bitter; it has little or no smell, and is so hard that it cannot be reduced into powder by beating, but requires to be filed down. Its narcotic operation is well exemplified in the effects it produces when given as a poison to dogs and other animals. It occasions extreme anxiety, para- lysis of the hinder extremities, convulsions and death; and on dissection, no marks of inflammation, or local affection, are to be discovered in the stomach. NARCOTICS. 149 As a narcotic, it has scarcely been used, though it has been recommended in mania, epilepsy, and hysteria. It has been given in dysentery and intermittent fever, in a dose of 5 grains twice a-day; but the use of it is so hazardous, that it has not been established in practice, nor received into the Pharmacopoeias. Prunus Lauro-Cerasus. Cherry-Tree Laurel. Icoaand. Monog. Pomacee. Folia. Europe. The leaves of this plant have an odour slightly fra- grant; their taste is extremely bitter. They possess a highly narcotic quality, which is extracted by infusion in alkohol or water, and is even brought over by dis- tillation in the state of an essential oil, which the water partly dissolves. And the very singular fact has been established, that the volatile principle in which the narcotic quality of this plant resides is the prussic acid. It has often been observed, that the odour of this acid is similar to that of the cherry laurel, peach blossom, and bitter almond. Bohn found, that the distilled water of the bitter almond contained prussic acid. Schroeder discovered it in the distilled water of the peach blossom and cherry laurel, prussiate of potash being obtained by distilling them from the alkali; and Bucholz succeeded in separating the prussic acid from the essential oil of the cherry laurel by agitation with an alkaline solution. This acid in its pure state has been further found to be highly narcotic; and the narcotic power of all these plants no doubt depends on it. The distilled water of the cherry laurel has long been known as a poison to animals, and its effects are those of a pure narcotic. It has not been employed in medi- cine, but a cataplasm prepared from the leaves has been used as an anodyne application to painful tumors and ulcers. 150 CHAPTER IV. OF ANTISPASMODICS. It is not easy to assign precisely the differences in kind of action between Narcotics and what are named Antispasmodics. The effects they produce are similar; they are capable of exciting the actions of the system, and they are often equally powerful in allaying pain and inordinate muscular action. But they do not in general produce that state of insensibility and diminished power which follows the application of narcotics, and this con- stitutes the difference between these classes. This might be supposed owing to a mere difference in strength; yet there seems also to be something farther than this, since antispasmodics produce no such effect in any dose, and since, although they are so much inferior to narcotics in these effects, they are equally powerful in repressing in- ordinate and irregular muscular action. This difference has; been explained on the supposition, that as stimu- lants they have less diffusibility and greater durability of action; or else, that with their stimulant operation, they have no direct power of diminishing the powers of the system. Considered under either view, they form an intermediate class between Narcotics, which are so highly diffusible, and Tonics, which are much more permanent in their stimulant operation; and experience shows, that they partake of the properties of both; seve- ral narcotics and tonics being frequently used as anti- spasmodics, and the powers of those which more parti- cularly constitute the class, in obviating spasmodic affections, being apparently connected principally with their stimulant power. From the name given to this class, their medicinal applications may be understood. Spasm is an irregular contraction of a muscle; sometimes the contraction is permanent; at other times it alternates with relaxation, ANTISPASMODICS. 151 but even then both are performed with more velocity, and the contractions are more powerful and more per- manent than natural. Many diseases depend on spas- modic action, and others are accompanied with affections of this kind. The medicines which obviate and remove such a state are termed Antispasmodics. Spasm may originate from various causes. One of the most frequent is a strong irritation, continually applied, such as dentition, worms, or the presence of any foreign substance in wounds. In such cases, narcotics must prove useful, by diminishing the irritability and sensi- bility of the system. Sometimes spasm appears to arise from mere debility, and the obvious means of removing this is by the use of tonics. Both narcotics and tonics, therefore, are occasionally useful as antispasmodics; such, for example, as opium and ether in the one class, and zinc, mercury and Peruvian bark in the other; and these are accordingly in common practice regarded as antispasmodics. But there are farther several substances which cannot be with propriety referred to either of these divisions, as musk, castor, assafoetida, galbanum, vale- rian, &c; they are in some measure intermediate; and it is to these that the name of Antispasmodic is more exclusively appropriated. Few general observations can be made on this olass of medicines. As their effect is not very permanent, they require to be given during the paroxysm of the spas- modic disorder, or a short time before its approach. For the same reason, the dose requires to be frequently re- peated. Those, however, which belong to the class of tonics, require an opposite mode of administration; their beneficial effects being obtained only from their con- tinued use. Some of those more strictly antispasmodics, stimulate the general system, and render the pulse more frequent; but in general they can scarcely be regarded as medicines of much power. 152 ANTISPASMODICS. Moschus. Castoreum. Oleum animale empyreumaticum. succinum, oleum and acidum succ1ni. Bitumen petroleum. Carbonas AMMONIjE pyro-oleosus. Ferula assafoetida. Bubon galbanum. Sagapenum Valeriana officinalis. Crocus sativus. Melaleuca cajuputi. NARCOTICS USED AS ANTISPASMODICS. Ether. Camphor. Opium. TONICS USED AS ANTISPASMODICS. Cuprum. Zincum. Hydrargyrus. Cinchona. Moschus. Musk. Moschus moschiferus. CI. Mammalia. Ord. Pecora. Asia. The animal which affords musk is a native of the olevated regions of the East of Asia. The musk appears to be a peculiar secretion, which is deposited in a small sac situated nigh the umbilicus of the male. It is brought from China, or from India, in small membranous bags, covered externally with coarse hair. The musk within is in grains, is slightly unctuous, of a black colour, hav- ANTISPASMODICS. 153 ing a strong durable smell, and a bitter taste. It yields part of its active matter to water, by infusion; by distil- lation the water is impregnated with its flavour; alkohol dissolves it, the impurities excepted. Musk is an antispasmodic supposed to be of conside- rable power; it is administered occasionally in the greater number of spasmodic diseases, especially in hysteria and singultus, and also in diseases of debility. In typhus fever it is employed to relieve subsultus tendinum, and other symptoms of a spasmodic nature. In cholera, it is given with the view of checking vomiting. Combined with ammonia, it has been celebrated for its power of arresting the progress of gangrene. With regard to its efficacy in some of these affections, its virtues have been perhaps exaggerated, and from this, as well as from its high price, it is not very often employed. Its dose is from 6 to 20 grains, repeated, if necessary, every five or six hours. It is best given in the form of bolus. To children, it has been given under the form of enema, as a remedy in the convulsions arising sometimes from the irritation of dentition. Offic. Prep.—Mist. Mosch. Lond.—Tinct. Mosch* Dub. Castoreum. Castor. Castor Fiber. Mammalia. Glires. The beaver, an amphibious quadruped, is a native of the North of Europe, Asia and America. Castor is a peculiar product collected in cells near the extremity of the rectum, in this animal. It is imported of superior quality from Russia, and an inferior kind from New England. The former is dry, slightly unctuous, of a reddish brown colour, intermixed with fibres, and co- vered with a tough membrane; it has a strong unpleasant smell, and a bitter acrid taste. The American castor is more shrivelled, and inferior in taste and smell. The active matter of castor is dissolved by alkohol, proof spirit, and partially by water; the tincture with alkohol is the least nauseous. Vol. I. U 154 ANTISPASMODICS. Castor is used as an antispasmodic, in hysteria prin- cipally, in a dose from 10 to 20 grains, or from 1 to 2 drachms of the tincture. From the experiments of Dr. Alexander, it appears to be a remedy of no power, as given in a quantity larger than its usual dose, it pro- duced no sensible effect on the system. Offic. Prep.—T. Castor. Ph. Ed. Lond. Dub. T. Castor. Comp. Ed. Oleum Animale Empyreumaticum. Empyreumatic Animal Oil. Ul. Cornu Cervi. The fresh bones or horns of animals, when exposed to heat in close vessels, afford an empyreumatic oil, derived from new combinations of the elements of the animal matter attached to the phosphate of lime, which is the base of bone. The oil is at first of a thick consis- tence, black colour, and extremely foetid smell, but by repeated distillations becomes thiner, nearly colourless and transparent, though it remains still foetid. In this state it has been used as an antispasmodic, in a dose of 10 or 15 drops. It retains its place in the Dublin Phar- macopoeia, under the name of Oleum Cornu Corvini Rectificatum, being obtained in the distillation of harts- horn or bones, for the preparation of carbonate of am- monia; but it is entirely discarded from practice. Succinum. Oleum et Acidum Succini. The bituminous substance, amber, though it has a place in the list of the Materia Medica of the dif- ferent Pharmacopoeias, is perfectly inert, and is in- troduced only as affording, by distillation, an empy- reumatic oil, which has been applied to some medi- cinal uses. This oil is at first thick and of a dark brown colour; but by repeated distillations with water it be- comes limpid, still retaining however a very foetid odour. It has been celebrated for its antispasmodic power, and has been employed in hysteria and amenor- rhea in a dose from 10 to 15 drops. It is now discarded ANTISPASMODICS. 155 from practice, or is used only occasionally as an ex- ternal stimulating application in paralysis and chronic rheumatism. Along with this oil, a peculiar concrete acid is pro- duced in the distillation, which is at first impure, but is purified by sublimation, or by solution and crystalliza- tion. It has a place in the Edinburgh and Dublin Phar- macopoeias, but appears destitute of any medicinal power, and is never applied to any use. Bitumen Petroleum. Petroleum Barbadense.Mineral Tar. Various kinds of liquid bitumens exist as natural productions, of different degrees of thickness, of a co- lour more or less deep, and also more or less volatile. That which has been usually kept in the shops, and applied to any medicinal use, under the name of Barba- does Tar, is thick, of a dark brown colour, having a smell that is foetid, and a warm bitter taste. It has an analogy to the preceding empyreumatic oils in its pro- perties; it has been used as an antispasmodic and su- dorific, and externally as a stimulating application in paralysis. Though it retains its place in the Pharmaco- poeias, it is scarcely ever used. Carbonas Ammonia Pyrg-Oleosus. Empyreumatic Carbonate of Ammonia. Sal Cornu Cervi. The bones of animals, when exposed to a suf- ficient degree of heat, afford a large quantity of car- bonate of ammonia, formed by new combinations of the elements of the animal matter contained in the bone. There is a similar production of empyreumatic oil, and with this oil the ammoniacal carbonate is always im- pregnated, whence it derives a peculiar foetid odour. It has also been supposed to derive from it certain medicinal powers, and has been used in preference to the pure carbonate of ammonia as an antispasmodic. Having been first procured from the bones of the deer, it has retained the name of Sal Cornu Cervi, and it still retains its place in the Dublin Pharmacopoeia; being 156 ANTISPASMODICS. procured dissolved in the water which distils over, and this being rectified by repeated distillations When thus rectified, it differs in little from pure carbonate of ammonia; and even combined with the empyreumatic oil, it has probably no additional medicinal efficacy, while from its fcetor it is unpleasant. Pure ammonia, disbulved in alkohol, is used as a solvent of the active matter of castor, assafoetida, and other antispasmodics, on the supposition that it concides with them in their action on the system. Ferula Assafoetida. Assafoetida. Pentand. Digyn. Umbellate. Gummi-Resina. Persia. Assafoetida is a concrete gum-resin, obtained by exudation from incisions in the roots of the plant; the juice, after it exudes, being hardened by exposure to the sun. It is in small masses, adhering to each other, of a variegated texture, yellow on the external surface, white within, having an extremely foetid smell, and a taste bitter and subacrid It consists of about two thirds of gum, and one third of resin, its taste and smell resi- ding in the resinous part. It yields all its virtues to al- kohol. Triturated with water, it forms a milky-like mixture, the resin being defused by the medium of the gum. Distilled with water, it affords a small quantity of essential oil, extremely foetid. Assafoetida is used as an antispasmodic in different nervous diseases, especially in hysteria, dyspnoea, dys- pepsia attended with flatulence, and tympanitis, and is superior in efficacy to any of the foetid gums. Its usual dose is from 5 to 20 grains, in the form of pill, or diffused in water. It is likewise given under the form of enema, in tympanitis, flatulent colic, in the violent hysteric paroxysm, and as a remedy against worms, 2 drachms being diffused in 8 ounces of warm milk or water; it is sometimes applied externally as a plaster.* » The watery solution of assafoetida is one of the best remedies in pertussis. Its use however, should always be preceded by emetics, or by pretty active purging with calomel.—Ed. ANTISPASMODICS. 157 Offic.Prep.—Alkohol Ammon. Foetid. Emp. Assa- foet. Pil. Assafoet. Comp. Tinct. Assafoet. Ed.—Mist. Assafcet. Lond. Dub. Enem. Foetid. Dub. BubonGalbanum. Galbanum. Pentand. Digyn. Umbellate. GummU Resina. Africa. Galbanum is obtained in the form of a milky juice, by exudation from incisions in the stem of the plant; when hardened it is in the form of a mass somewhat variegated in its texture, tenacious, of a yellowish brown colour, having a foetid smell, and a bitter acrid taste. Alkohol dissolves its resin, in which its powers have been supposed to reside; proof spirit dissolves it entirely, the impurities excepted. Triturated with water, it is diffused, and forms a milky-like fluid; by distillation it affords about one twentieth of its weight of essential oil. Galbanum has the virtues of the foetid gums, and is used for the same purposes; but being inferior in strength to assafoetida, it is less employed. Its dose is ten grains. Externally, it is more frequently used as a discutient to indolent tumors, and as a stimulant to pro- mote suppuration. Offic. Prep.—Pil. Galb. Comp. Lond.—Tinet. Galban. Dub.—Emp. Galb. Comp. Lond. Dub. Sagapenum. Gummi-Resina. This gum-resin, usually imported from Alexandria, is the produce of an unknown tree said to be a native of Persia. It is in small masses, of a yellow colour, having a smell slightly foetid, and a pungent nauseous taste; it is soluble in proof spirit; by distillation it affords a small quantity of essential oil. Its virtues and uses are the same as those of assafoe- tida, to which, however, it is much inferior in power, and is therefore seldom employed. Its dose is from ten to twenty grains. It is sometimes applied externally as a discutient. 158 ANTISPASMODICS. Valeriana Officinalis. Wild Valerian. Triand. Monogyn. Ag* grtgate. Radix. Indigenous. The root of this plant, which is the part used in me- dicine, consists of a number of slender fibres twisted, and attached to one head, of a light brown colour, hav- ing a 6mell strong and unpleasant, and a warm bitter taste. Iu active matter is dissolved equally by water and alkohol, and appears therefore to consist of extrac- tive matter, with perhaps a small portion of tannin, as its infusion changes colour on the addition of sulphate of iron. By distillation, water is impregnated with its flavour, but not with its taste, and no sensible quantity of essential oil is obtained. Valerian is one of the principal modern antispasmo- dics, and is employed in hysteria, chorea, and epilepsy, where these depend not on organic derangement, or on any permanent irritation, but on increased susceptibility of the nervous system. Sometimes, also, it is used with advantage in hemicrania. Its dose is from one scruple to one drachm, three or four times a-day, which is in- creased gradually as far as the stomach can bear it. Sometimes it is taken under the form of infusion. Offic. Prep.—Tinct. Valer. Tinct. Valer. Ammon. Ph. Lond. et Dub—Extr. Valer. Infus. Valer. Dub. Crocus Sativus. Saifron. Triand. Monogyn. Liliacee. Floris Stigmata. Indigenous. This substance is composed of the stigmata which crown the pistil of the flower. These are pressed toge- ther, and form a soft mass of intermixed fibres, named Cake Saffron; when dried separately, they form Flower Saffron. The former is what is usually kept in the shops. It is somewhat moist, of a deep reddish yellow colour, its flavour is aromatic and diffusive, tne taste warm and bitterish. The active matter is equally ex- tracted by alkohol, water, proof spirit, and vinegar; the residuum, which is not more than six parts out of six- teen, being inert ligneous fibre. By distillation with water, a small quantity of essential oil is obtained. ANTISPASMODICS. 159 Saffron was formerly regarded as a very active medi- cine, possessed of high stimulant and antispasmodic power, and requiring, it was imagined, to be given with much caution. Experience has proved it to be nearly inert, and it is now banished from medical practice. It is used as a popular remedy in the exanthemata, parti- cularly in small-pox. Offic. Prep.—Tinct. Croci. Ed. Dub.—Syr. Croci. Lond. Melaleuca Cajuputi. Polyadelph. Polyand. Hesperidee. Oleum Volatile. 01. Cajepute. Cajeput Oil. India. The essential oil, known by the name of Cajuput Oil, was supposed to be obtained from the Melaleuca Leucadendron; but, from later investigation, it appears to be procured from another species, to which the name of Melaleuca Cajuputi has been given. It is obtained by distillation from the leaves and fruit, has a green or yel- lowish colour, a strong fragrant odour, somewhat similar to that of camphor, and an extremely pungent taste. It is highly volatile and inflammable. This oil has been used as a highly diffusible stimulant and antispasmodic, in tympanitis, flatulent colic, hys- teria, palsy, chronic rheumatism, and various other dis- eases of debility. Its dose is three or four drops. It is also applied externally to relieve rheumatic and gouty pains, and it often succeeds in relieving the pain of toothach, when applied to the affected tooth. Several substances are employed as antispasmodics, and which I have therefore placed in the table, which more strictly belong, however, to some of the other classes. Under these, therefore, their history is given, including the notice of those few applications of them as remedies, connected with their antispasmodic power. 160 CHAPTER V. OF TONICS. By Tonics, are understood those substances, the primary operation of which is to give strength to the system. It has been conceived, that muscular vigour depends on a certain degree of tension, or tone as it is termed, of the muscular fibre; and those substances which renew that vigour when impaired, have been con- sidered as restoring this due degree of tension, and have thus received the appellation of Tonics. They are'not, however, to be considered as acting by producing any mechanical change in the state of the solids, as this opi- nion implies. They act upon the living principle, and, so far as their action is understood, are stimulants of considerable power, permanent in their operation. The distinction has been already pointed out between stimulants, which is founded not so much on a diffe- rence in their power, as in the quickness with which their full effect is produced, and in the transient nature of that effect. If a medicine suddenly raises a high state of excitement, this is as quickly followed by propor- tional languor or debility, and the changes from both modes of action, in the state of the functions of the body, are sufficiently evident. But, if the stimulant operation be more slowly exerted, any change is much less con- spicuous, and the succeeding collapse takes place to no considerable extent; but even when the administration of the remedy is suspended, the effect is merely a gra- dual abatement of excitement, counteracted even by the action of the stimulants habitually applied. On these principles, the action of tonics is to be explained. It is only by their stimulant operation that they can obviate debility; and as their effect is gradual, their action is not followed by that exhaustion and diminished susceptibi- lity which invariably follows from excitement suddenly TONICS. 161 raised. If their administration, however, be carried to excess, or be continued too long, it may at length di- minish the powers of the system; and if employed in a state of health, or high vigour, their effects may be injurious. Tonics act primarily on the stomach, the action they excite in that organ being conveyed generally by ner- vous communication to the rest of the system. This is evident, from their effects often taking place in a short time; and there are experiments which prove, that when some tonics, as Peruvian bark, have been taken for a considerable length of time, no portion of them can be discovered by any chemical test in the blood. There are some of them, however, especially the metallic tonics, which are received into the circulation. The stimulating effect of tonics is principally to be observed from their continued administration; they in- crease gradually the force of the circulation, promote the action of the digestive organs, augment the secretions, or moderate them when they have been morbidly in- creased, and give vigour to the muscular system. From the action of some of the more powerful remedies of this class, these effects are apparent, even in a short time. The diseases in which they are employed, must be obviously those of diminished power. Tonics may be subdivided into those derived from the mineral, and those from the vegetable kingdoms: the former division comprehends several of the metals, and one or two of the earths. Under the vegetable tonics are comprised a number of substances possessing bitter- ness, and an aromatic pungency. These two qualities are generally blended in the most powerful tonics be- longing to the vegetable kingdom; and there is a transi- tion from these to the more pure bitters and aromatics. The stimulating action of the latter is rather too local and transient to give rise to much permanent tonic effect; yet they can scarcely be placed under any other class, and I have therefore associated them with the substances with which they are thus connected. Vol. I. X 162 TONICS. FROM THE MINERAL KINGDOM. Argentum. Hydrargyrum. Ferrum. Zincum. Cuprum. Arsenicum. Bismuthum. Barytes. Calx. acidum nitricum. oxy-murias potassie. FROM THE VEGETABLE KINGDOM. Cinchona officinalis. Cinchona caribjea. Cinchona *loribunda. Aristolochia serpentaria. dorstenia contrayerva. Croton ELEUTHERIA. CUSPARIA FEBRIFUGA. SWIETENIA FEBRIFUGA. SWIETENIA MAHAGONI. COLOMBA. Quassia simarouba. Quassia excelsa. Gentiana lutea. Anthemis nobilis. Citrus aurantium. Citrus medica. Laurus cinnamomum. Laurus cassia. Canella alba. Myristica moschata. Caryophyllus aromaticus. Capsicum annuum. Piper nigrum. Piper longum. Myrtus pimenta. Amomum zingiber. Amomum zedoaria. Amomum repens. Carum carui. coriandrum sativum. PlMPINELLA ANISUM. Mentha piperita. TONICS. 163 TONICS FROM THE MINERAL KINGDOM. These are in general more local in their action than the vegetable tonics; they either operate more directly on the stomach without their action being so quickly extended to the whole system, or they act by being re- ceived into the circulating mass. Hence they produce less immediate general excitement, and it is only from their continued administration, generally in small doses, that their tonic effect is obtained. The analogies from which I have placed together the substances associated under this division, are perhaps somewhat remote and imperfect; and, to some of them, the appellation of tonic may be considered as applied by rather too free an ex- tension of the term. But such imperfections in the clas- sification of substances, from their action on the living system, are in the present state of medical science un- avoidable to a certain extent. The substances, with re- gard to which this objection may be urged in the present case, could scarcely be referred with propriety to any other class: affinities may be traced in their operation, sufficient to connect them by their medicinal effects; and, even considered individually, the claim of each may be established to a certain degree of tonic power. Argentum. Silver. This metal is distinguished by its pure white colour, its high degree of lustre, and its great ductility and mal- leability. It is not very susceptible of oxidation; it does not suffer that change from exposure, even in a state of fusion, to the atmosphere. Those acids which yield oxygen readily oxidate and dissolve it, particularly nitric acid, which is hence employed as its usual solvent. The solution, when evaporated, affords the nitrate of silver in a crystalline form. It appears that nitrate of silver was sometimes em- ployed by the older physicians, but the harshness and violence of its operation led to its disuse. More lately, » 164 TONICS. it has been introduced as a remedy in epilepsy,—a dis- ease which, when not depending on organic derange- ment, is frequently connected with morbid suscepti- bility, and which tonics sometimes remove. The advan- tage derived from the administration of nitrate of silver has been established on the testimony of Dr. Sims, Dr. Cappe, Dr. Bostock, and others. The dose is a quarter of a grain of the crystallized nitrate, which may be given three or four times a-day. Distilled water must be employed to dissolve it, as spring water would de- compose it; and the solution may be made into pills with bread. It sometimes acts as a cathartic, and if it occasion much cathartic effect with griping, or excite nausea, the dose must be diminished. Dr. Cappe has related a case of Angina Pectoris, the symptoms of which were removed by a similar administration of nitrate of silver.* Hydrargyrum. Hydrargyrus. Argentum Vivum Mercu- rius. Mercury or Quicksilver. It has not been usual, in arrangements of the articles of the Materia Medica from their medicinal power, to place mercury under the class of tonics, but rather under that of sialogogues. Its power, however, of exciting the salivary discharge, is merely a secondary effect, not constant nor uniform, and which is not essential to its efficacy in any disease. On the contrary, its tonic power * In this city, nitrate of silver has been sufficiently tried in epi- lepsy, and not with much success. If it be admitted to palliate symptoms, or in some instances to protract the return of the paroxysms of this disease, I suspect this is all which could be said of its efficacy. More I am inclined to be- lieve has been done with it in chorea. Do we not do injustice to the remedy by administering it in too small doses? By Dp. Povvel, a distinguished practitioner of London, who is said to employ it with signal advantages in most of the cases of neuroses, from two to five grains are given every six hours. In one case of epilepsy I gradually augmented the dose to eighteen grains in the twenty-four hours, without producing any ^oublesome effect. It did not however cure the disease.—Ed. TONICS. 165 is its primary operation; it is the most general stimulant belonging to the Materia Medica, pervading every part of the system; acting, as Cullen has remarked, as a sti- mulus to every sensible and moving fibre of the body, and producing the most permanent effects. Hence, it is the most general evacuant we possess; and from its sti- mulant operation, exerted directly or indirectly, we are able to explain its utility in many diseases. This metal is peculiarly distinguished by its fluidity at all natural temperatures, with the exception of the in- tense cold that sometimes prevails in very northern regions. Its congealing point is —40° of Fahrenheit. In its liquid state, it has the perfect opacity and lustre cha- racteristic of metals, and likewise the property of great density, its specific gravity being to that of water as 13.5 to 1 nearly: it boils at a temperature a little above 600°, and when boiling suffers oxidation from the action of the atmospheric air. It is oxidated even at natural temperatures, when subjected to agitation; or still more easily, when triturated with any viscid matter, which is interposed between its globules, extending their surface. Quicksilver is usually obtained from the ore in which it is combined with sulphur, this being submitted to heat mixed with iron or lime, either of which combines with the sulphur, and the mercury is obtained by dis- tillation. The quicksilver of commerce is sometimes impure, or adulterated by the intermixture of other metals, particularly lead and bismuth. This may be suspected when the metal loses its lustre speedily, and is covered with a gray film, or from its diminished mobility, in consequence of which its globules do not preserve exactly the spherical form, nor unite easily with each other; and it may be discovered, with more certainty, by exposing it to a heat sufficient to volatilize the quicksilver, when any other metal present will re- main. It is best purified by distillation from iron filings in an iron retort. Mercury is not, in its metallic state, applied to any 166 TONICS. medicinal use; but under various forms of preparation, it is extensively employed, and affords a series of very active remedies. When rendered active on the system by any of the modes of preparation to which it is subjected, it operates as a very powerful and general stimulant; as from being received into the blood, it is enabled to act on every part of the system.* Hence when given in moderate quantity, it communicates general vigor: it increases the force of the circulation when this has been languid; by the increased vascular action which it ex- cites, it gives to the blood the disposition to assume the buffy coat; and by its stimulant operation on secreting organs, it promotes the secretions, and hence is the most general evacuant we have. On its general stimulant operation probably depends its efficacy in diseases con- nected with spasmodic action, as tetanus and hydro- phobia; and perhaps also that derived from it in various forms of fever, particularly the remitting fever of warm climates, and yellow fever; and its local operation is dis- tinctly marked in the advantage derived from it in chronic hepatitis, and other varieties of visceral and glandular obstructions, and in the different species of cutaneous eruptions. Its most important medicinal operation, however, is that displayed in removing the disease induced by the syphilitic poison. In this, its power is nearly, if not alto- gether specific; no article of the Materia Medica could be substituted for it; and there may be affirmed of it, what cannot with equal justice be said of any remedy employed in the treatment of any other morbid affection, that if duly administered, it will scarcely ever fail in effecting a cure. It is difficult to assign any satisfac- tory theory of its operation. Its efficacy has been ascrib- ed to its general evacuant power, in consequence of * It is not true, that mercury is taken into the circulation, as I have endeavoured to shew, in the former part of this volume, under the head of modus operandi of medicines.—Ed. TONICS. 167 which the syphilitic virus is discharged from the body. But the speedy disappearance of the local symptoms of syphilis under its use, affords a proof that it operates on some other principle; no similar advantage is derived from other evacuants; and its efficacy is not proportional to the evacuation it excites, but is frequent displayed where this is altogether insensible. The opinion has been advanced, that it acts as an antidote to the vene- ral virus, neutralizing it somewhat in the manner in which one chemical agent subdues the properties of another,—an opinion extremely vague and hypothetical, and rendered improbable from the consideration of the very small quantity of some of the more active prepa- rations of mercury, from which a cure may be obtained, compared with the large quantity of others less active, that requires to be administered. The explanation ad- vanced by Mr. Hunter, that the efficacy of mercury in the treatment of syphilis depends on its general and permanent stimulant operation on the system, by which it induces and keeps up an action incompatible with that morbid action which constitutes the disease, until the virus is destroyed by the chemical changes going on in the system, or until it is eliminated from the body by the usual excretion, is on the whole most probable: it rests on a principle undoubted, that there are states of morbid action incompatible, so that one suspends the action of the other; and mercury does exert a very general action, inducing and keeping up what may be regarded as a morbid state. The mode of administering mercury, for the cure of the venereal disease, under all its forms, is now ascer- tained with sufficient precision. There is no advantage in giving it so as to induce profuse salivation; this is even to be avoided as hurtful; at the same time, it is proper that salivation should be excited to a certain extent, not probably as essential to its efficacy, but as a proof of its full action on the system being obtained. This is kept up for a certain time, longer or shorter, according to the state of the symptoms, and the previous 168 TONIC!*. continuance of the disease. Exposure to cold is avoided, as being liable to cause the more partial operation of mercury on the salivary glands; and the state of irrita- tion is diminished, or determination to the intestines producing purging is obviated, by the exhibition of an opiate. When profuse salivation occurs, the remedies employed to check it are cathartics in moderate doses, small doses of opium, the application of a blister to the throat, and the administration of sulphuret of potash; the last being employed from the doubtful hypothesis, that its chemical agency may neutralize the mercury. Free exposure to a cool dry air is, according to the observation of Mr. Pearson, more effectual than any other method. When the morbid irritation, from the action of mercury, rises too high, producing a state of exhaustion, which sometimes proceeds rapidly to an alarming extent, the administration of the remedy must be immediately suspended; and in this case also, expo- sure to a cool atmosphere is advantageous.* The preparations of mercury, medicinally employed, are those in which it is oxidized, in which the oxidized metal is combined with an acid, or in which either the metal or the oxides of it are combined with sulphur. The gray oxide, formed by the trituration of mercury, is the basis of a number of preparations. In these, the metal has been supposed indeed to be merely mechani- * There is nothing more desiderated in the practice of physic than a remedy to check the inordinate action of mercury. Cathar- tics, so far from answering this purpose, have invariably a con- trary effect. 1 do not know, indeed, so certain a mode of develop- ing the mercurial action as by copious purging. In all cases where I meet with any difficulty of exciting salivation, I resort to this method, and commonly with success. The more active the purge the better. We have no specific means of controlling the mercurial im- pression. The free use of opium to subdue irritation, a generous diet, and an exposure to fresh, though a dry air, I have found the most beneficial plan of treatment. To alleviate the local distress, any of the ordinary gargles are useful, and where much swelling and inflammation exist, a blister should be applied around the throat.—Ed. TONICS. 169 cally divided; but in its metallic state, mercury does not appear to exert any sensible action on the living system, and the activity of it in these preparations is a proof that it is oxidated. This is established more directly; quick- silver, by agitation, being converted into a black powder, which is soluble in muriatic acid, which metallic mer- cury is not. This oxidation is facilitated by the quicksilver being triturated with any viscous substance which facilitates the division of its globules. Jj^trituration with muci- lage of gum arabic, a preparffifon is obtained, named Plenk's Mercurial Solution, the operation of which is extremely mild. Rubbed with chalk, it forms the Hy- drargus cum Creta of the London Pharmacopoeia, a preparation having nothing to recommend it. The Mer- curial Pill is, of all the preparations adapted to affect the general system, the one most commonly employed, and is perhaps equal to any other, having the advantage of not being liable to produce much irritation, while we can depend on the certainty and permanence of its ac- tion. It is prepared by triturating quicksilver with con- serve of roses, and adding a sufficient quantity of starch to form a pill mass. In a dose of eight grains, morning and evening, it soon affects the general system; in a larger dose, it is liable to occasion purging. Triturated with lard, quicksilver soon loses its metallic form; and the ointment, after it has been kept for some time, con- tains little metallic matter, the unctuous matter proba- bly promoting the oxidation^ The oxide is diffused through the lard, and it has been conjectured, is in part too combined with sebacic acid, formed from the oxy- genation of the fat. Rubbed on the skin, in the quantity of one drachm of the strongest ointment, (that com- posed of equal parts of quicksilver and lard,) it is forced through the cuticle, and is taken up by the absorbents; the system is thus affected, without the unpleasant con- sequences of nausea and purging, sometimes occasion- ed by the internal administration of even the mildest mercurial preparation; this method is emploved, there- Vol.T. Y 17U TONICS. fore, where, from the state of the system, these affec- tions are liable to be produced. Where it is necessary too to give the remedy in a large dose, or to bring the system speedily under its action, mercurial friction is employed, along with the administration of some of the mercurial preparations by the mouth. And, lastly, it has been supposed, that in certain local affections, par- ticularly bubo, some advantage is derived from the mer- cury being conveyed through the affected gland. The Mercurial Pla^to^. is the metal triturated with melted resin and oil, anWnixed with litharge plaster: it is sometimes applied to indolent glandular tumors as a discutient. Its power is supposed to be increased by the addition of gum-ammoniac, and this compound plaster has a place in the London and Dublin Pharmacopoeias. Mercury oxidated by exposure to atmospheric air, at a high temperature, gives an oxide in scales of a red colour, containing about seven of oxygen in one hun- dred parts. This, the red oxide, (Oxidum Hydrargyri Rubrum of the London Pharmacopoeia,) affords a pre- paration, supposed by some to be the most uniform in its strength, and most certain in its operation, of all the mercurials. Its dose is one grain night and morning. It is more active than the gray oxide, but is more liable to produce irritation. Various preparations are obtained from the metal oxidated by the acids. The nitrate of mercury decom- posed by heat, furnishes what is named Oxidum Hy- drargyri Rubrum per Acidum Nitricum by the Edin- burgh College, Hydrargyri Nitrico-Oxydum by the London. It is probably not an oxide, but a sub-nitrate, and, from the acid combined with it, is derived its escharotic power, for which only it is employed, being applied externally to change the diseased surface of ulcers, or to other purposes for which escharotics arc used. When the nitrate of mercury, containing the mercury in a low state of oxidation, is decomposed by ammonia, a precipitate is thrown down of a gray colour, which TONICS. 171 appears to be nearly a pure oxide. It is the Oxidum Hydrargyri Cinereum of the Pharmacopoeias; is com- paratively mild in its operation, and is frequently em- ployed, its dose being one or two grains. It is also sometimes used under the form of ointment, as a mode of applying mercurial friction. Mercury, oxidated by sulphuric acid, forms the sul- phate of mercury, which, decomposed by the affusion of boiling water, affords a yellow powder, the Sub-sul- phate, or as it was formerly named, Turbith Mineral. This acts with too much violence to be used as a mer- curial. In a dose of three or four grains, it acts as a powerful emetic, and it is sometimes used as an errhine. The preparations in which the mercury is saturated with an acid, are very active. The nitrous solution of it is highly caustic. Mixed with lard, it forms an ointment, Unguentum Nitratis Hydrargyri, used with much ad- vantage in cutaneous diseases. Mercury, oxidated and combined with muriatic acid, forms two very active preparations, differing in the de- gree of oxidation, and in the proportion of acid with which the oxide is combined. The one has been long known by the name of Corrosive Sublimate of Mercury, the other by that of Mild Sublimate or Calomel. The former is now named Muriate of Quicksilver by the Edinburgh College, and Oxy muriate of Quicksilver by the London College; the latter by both Colleges Sub- muriate of Mercury;—names not sufficiently distinc- tive, and chemically incorrect. The old distinguishing epithets are still the least ambiguous, and even as a chemical nomenclature are properly used. The first of these, Corrosive Muriate of Mercury, is composed of the metal highly oxidated, and this oxide is combined with a large proportion of muriatic acid. The proportions are 69.6 mercury, 12.3 oxygen, and 18 of acid. It is soluble in water and in alkohol, has a taste styptic and metallic, and exerts a degree of escharotic power. It is the most virulent of all the preparations of this metal, and cannot be given with safety in a larger 172 TONICS. quantity than one fourth of a grain: its medium dose is one sixth or one eighth. It acts more generally on the system than any other preparation, and very speedily arrests the progress of syphilis, advantages which have frequently recommended its use. But it is liable to be violent in its operation, and its effects have been sup- posed not to be permanent, the disease frequently re- turning in the same or some other form; hence, as an antisyphilitic, it is not much employed in regular prac- tice. A very dilute solution of it is used as a collyrium in venereal ophthalmia, as a gargle in venereal sore- throat, and as a lotion in some cutaneous affections. The Mild Muriate of Mercury, k.-r Calomel, is ob- tained by triturating the corrosive muriate with nearly an equal part of the metal, and favouring their mutual action by the action of heat, the product being sublim- ed. vThe additional metallic mercury which is thus brought into combination, shares the oxygen and the acid of the corrosive muriate; so that the whole of the metal is in a lower degree of oxidation, and this oxide >«•■ is combined with less muriatic acid. The quantity of acid, however, is as much as the oxide requires to com- bine with it, and hence the product is not a sub-muriate. The proportions of its principles, according to its analy- sis by Chenevix, are mercury 79, oxygen 9.5, and acid 11.5. It is mild in its operation, and is one of the most useful of the mercurial preparations. In syphilis it is given in the dose of a grain night and morning; it is likewise administered with the greatest advantage in glandular obstructions, dropsy, chronic rheumatism, hydrocephalus, hydrophobia, and in the fevers of warm climates, being given in several of these diseases in much larger quantities. It not only produces the general effects of a mercurial, but also, when given in sufficient doses, acts as a cathartic: it is often employed to pro- mote the operation of other cathartics; and its peculiar determination to the intestines probably adapts it belter to the treatment of diseases of the neighbouring organs, or to states of disease connected with affections of the intestinal canal. TONICS. 173 Muriate of Mercury and Ammonia, Hydrargyrus Prascipitatus Albus of the London Pharmacopoeia, is prepared by decomposing corrosive muriate of mercury by ammonia. A precipitate is obtained, which consists of oxide of mercury combined with a portion of mu- riatic acid and a small quantity of ammonia, the propor- tions being 81 of oxide, 16 of acid, and 3 of ammonia. It is too acrid for internal use, but is employed exter- nally as a mild escharotic, and as an application in various cutaneous affections. An ointment adapted to these purposes has a place in the London and Dublin Pharmacopoeias. With acetous acid mercury forms the Acetis Hydrar- gyri,—a preparation which, as the basis of Keysets pill, was at one time much celebrated for the mildness of its operation; it is given in a dose of from 2 to 5 grains; its operation has been supposed, however, to be uncertain, and it has fallen into disuse. With phosphoric acid, Phosphate of Mercury is formed,—a preparation of considerable activity and cer- tainty, but which, though introduced, has not been es- tablished in practice. The dose of it is one grain. These, as well as other saline compounds of mercury, are most easily obtained by adding to a solution of nitrate of mer- cury a solution of a compound salt, containing the acid with which the oxide of mercury is designed to be com- bined. Thus, to form the acetate, a solution of acetate of potash is added; or to form the phosphate, a solution of phosphate of soda. United with sulphur, mercury forms two preparations, the black sulphuret, and the ied. In both of them the metal has been supposed to be oxidized, and in the red a large quantity of oxygen has been supposed to be con- tained. This has not been established, however, and it is probable that they are metallic sulphurets without oxy- gen. The black sulphuret, formerly named Ethiops Mi- neral, is prepared by triturating equal parts of mercury and sulphur together, so as to form a black powder. It is a very inactive preparation, and has been used only as 174 TONICS. an anthelmintic, in a dose to an adult of one scruple or half a drachm. The red sulphuret, or Cinnabar, is the mercury united with about one-sixth of its weight of sulphur by sublimation. It is applied principally by fumigation, with the view of stopping the progress of venereal ulcers, being converted into vapour by being laid on a hot iron, and this vapour being directed on the part.* Ferrum. Iron. This metal is the one which has been regarded as most salutary to the animal system. It exists as a con- stituent part of the blood, and other varieties of animal matter, and its acts as a powerful tonic, increasing the power of digestion, quickening the circulation, and caus- ing the blood, it is said, to assume a more florid hue, promoting the secretions, or restraining them when they have been morbidly increased. It has been considered as doubtful whether it acts by being received into the mass of blood; its existence as a constituent principle of the blood, and the slowness of its operation, render it pro- bable that it does. The diseases in which iron is used are those of chronic debility, especially chlorosis, dyspepsia, hypo- * The preceding account of the practical application of mercury is exceedingly defective. But it is not easy to improve it, in the narrow limits of a note, or, without indeed indulging in a discussion, wholly inconsistent with the strictly elementary nature of the pre- sent work. Confessedly, we have no article possessed of such various powers, or which in the practice of this country especially, is employed in so many and diversified cases. There is, perhaps, no disease either acute or chronic, in which mercury, under certain circumstances, may not be advantageously exhibited. It was, at least, the advice of the late Dr. Bond, who was deservedly one of the most distin- guished of our physicians, that in all cases where other modes of treatment fail, we should resort, as a dernier resource, to mercury. By the adoption of this rule, he acquired immense celebrity for his extraordinary cures, and did more undoubtedly, than any one else, to raise our medicine to its elevated rank in the Materia Medica of the United States.—Ed. TONICS. 175 chondriasis, hysteria, paralysis, and rickets. It succeeds best when given in small doses continued for a conside- rable time. The Limatura Ferri, or Filings of Iron, are given in any dose from one scruple to a drachm or two; their activity is probably dependent on the oxidation they may- suffer in the stomach, from the action of the gastric fluids. The Carbonate, or Rust of Iron, Carbonas Ferri, Rubigo Ferri, is the metal oxidated by exposure to the air with moisture, and combined with carbonic acid; it is more active than the pure metal, and less irritating than the saline preparations. It is given in a dose from 5 to 20 grains. Another form of it, supposed to be more pure, is what is named Carbonas Ferri Praecipitatus, prepared by adding a solution of carbonate of soda to a solution of sulphate of iron, washing and drying the pre- cipitate formed by the mutual decomposition. Muriate of Iron and Ammonia, of the Edinburgh Pharmacopoeia, what is named by the London College Ferrum Ammoniatum, is obtained, by sublimation, from a mixture of muriate of ammonia and red oxide or carbonate of iron. It is an active preparation, but liable to be variable in composition. It is given in a dose from 5 to 10 grains. Dissolved in diluted alkohol it forms an officinal tincture, the dose of which is 30 drops. The Muriate of Iron employed under the form of tincture, prepared by dissolving black oxide of iron in muriatic acid, and diluting the solution with alkohol, Tinctura Ferri Muriati, is a very active preparation; sometimes too much so to admit of being used in an irritable state of the stomach. Its dose is 10 or 15 drops diluted with water, or taken in wine. Sulphate of Iron is formed in the large way, by the oxygenation of the native sulphuret by exposure to air and humidity; or it is obtained more pure by dissolving iron in diluted sulphuric acid, and evaporating the solu- tion. It crystallizes in rhomboidal prisms of a green colour. It is one of the most active preparations of the 176 TONICS. metal, and is not unfrequently prescribed in amenor- rhoea. Its dose is from one to five grains. The red sul- phate, in which the metal is more highly oxidated, is also employed as a tonic in a similar dose. The Tartrate of Potash and Iron has a place in the London Pharmacopoeia, though not much employed in practice. It is prepared by rubbing equal weights of iron filings and super-tartrate of potash with water, ex- posing the mixture to the action of the air, drying the mass, and again subjecting it to the action of water to render the oxidation and combination of the iron more complete. The preparation is a mild one, and can be given to the extent of 10 or 15 grains as a dose. A si- milar preparation, in which the iron is more highly oxidated, and its combination with the tartaric acid pro- bably more perfect, is obtained by a process given by the London College, in which carbonate of iron and su- per-tartrate of potash are boiled with a portion of water, the liquor filtered, and evaporated until on cooling it form a saline mass. This, in a dose of three or four grains twice a-day, acts not only as a tonic, but also as a diuretic, and, from the combination of these powers, has been employed with advantage as a remedy in dropsy. The Wine of Iron, which has a place in the London and Dublin Pharmacopoeias, prepared by digesting iron- filings in white wine, is another form under which the tartrate is used; the metal being dissolved by the tar- taric acid of the wine. Its dose is one or two drachms. Acetate of iron has been introduced by the Dublin College, being prepared, according to one process they have given, by digesting carbonate of iron in acetic acid; according to another, by rubbing together acetate of potash and sulphate of iron until they become soft; dry- ing this with a moderate heat, and digesting it with alkohol. Of the tincture thus formed, 20 or 30 drops are a dose. The London College have given a place to a prepa- ration of iron, (Liquor Ferri Alkalini), of rather a sin- TONICS. 177 gular nature. Iron is dissolved in nitric acid largely diluted; and to this solution a solution of sub-carbonate of potash is added, while effervescence is excited: the liquor, after standing for six hours, is poured oft. It is probably a ternary combination of oxide of iron, potash and carbonic acid; any nitric acid remaining undecom- posed in the oxidation of the iron, being probably com- bined with a portion of potash, and this nitrate being deposited. This preparation has been long known by the name of Stahl's Martial Alkaline Tincture. It is not very apparent what advantage it has over others in common use, and it is always liable to be variable in strength. The Mineral Chalybeate Waters afford another form under which iron may be administered. The iron is ge- nerally dissolved in them by the carbonic acid; and from the state of dilution they are often used with more ad- vantage than the more active preparations of the metal. Zincum. Zinc. This metal is of a white colour, with a shade of gray; it is brittle, except at a temperature between 200 and 300 of Fahrenheit, when it has considerable ductility and malleability; it is fusible at a heat approaching to that of ignition, and when raised to that temperature burns with a bright flame, forming a white oxide. Zinc exerts no sensible action on the system in its metah^cstate; it is employed therefore under various forms (^preparation. White oxide of zinc, obtained from the combustion of the metal, has been employed as a remedy in various spasmodic affections, particularly chorea and epilepsy, in a dose of five grains, gradually increased. There are cases on record where a cure was obtained; but it does not appear to be very active or certain in its operation, and it is not often prescribed. An ointment composed of it is used as a healing cerate, and as an application in ophthalmia. Vol. I. Z 178 TONICS. There is a substance named Impure Oxide of Zinc by the Edinburgh College, long known by the appella- tion of Tutia, the nature and origin of which are not very well ascertained. It has been supposed to be arti- ficial, and to be prepared from oxide of zinc obtained in the roasting of zinc ores, which is afterwards mixed with clay. It is used sometimes as the basis of a cerate employed as a dressing to wounds, or applied to the eye in some forms of ophthalmia. What has been named Calamine Stone, (Lapis Cala- minaris), is regarded as a carbonate of zinc; and it gene- rally is bo, though there are varieties of it composed of oxide of zinc and siliceous earth. It is employed only- ex ternally as the basis of the common healing cerate. Sulphate of Zinc, formed by exposure of the native sulphuret to air and humidity, is obtained by evapora- tion of its solution in a solid mass, forming the white vitriol of commerce; or it is procured more pure, and in a crystalline form, by evaporation of the solution of zinc in diluted sulphuric acid. It has been employed in the same cases as the oxide, and Dr. Cullen has observed that it is possessed of the same powers; it has likewise been given as a tonic in intermittent fever, and as a tonic and astringent in chronic dysentery. It is difficult, how- ever, to regulate its administration so as to obviate the nausea which it is liable to occasion. It is given some- times as a powerful emetic, in a dose from 10 to 20 grains, particularly where the stomach is not easily rous- ed to action, as where a narcotic poison has been swal- lowed. Its solution is a common astringent injection in gonorrhoea in the strength of a grain and a half to an ounce of water; and nearly of the same strength it is often employed as a collyrium in ophthalmia. Acetate of Zinc, under the form of solution, has a place in the Edinburgh Pharmacopoeia, being obtained by mixing solutions of acetate of lead and sulphate of zinc, when sulphate of lead is precipitated, and the acetate of zinc remains dissolved. It is used as a colly- rium in ophthalmia, and an astringent injection in gonorrhoea. TONICS. 179 Cuprum. Copper. This metal is not like the greater number of the metals, insipid and indorous; it has an unpleasant styptic taste, and when rubbed a preceptible smell. It is extremely noxious to animal life. Still, when properly administered, it proves a remedy of some value, and like zinc has some claim to be ranked as a tonic, from its successful operation in epilepsy, chorea, and several other spasmodic affections dependant on or connected with debility. Copper is employed in various forms of saline com- bination. The sulphate is rather too active to admit of internal administration; even in a very small dose it ex- cites nausea and vomiting; and as a powerful emetic it is employed, where from the state of the stomach it is difficult to excite vomiting, as where a narcotic has been taken in too large a quantity; the dose being from 2 to 5 grains, or even larger, according as it is more diffi- cult to excite vomiting. Externally it is used as an astringent and escharotic,—applications of it to be after- wards noticed. Sub-acetate of Copper, Verdegrease as it has been named, is also employed on account of its escharotic power. The preparation named Ammoniuret of Copper (Am- moniaretum Cupri, Cuprum Ammoniatum) is the one usually employed to obtain the action of copper on the system. It is prepared by triturating sulphate of copper and carbonate of ammonia together, and is either a ternary compound of oxide of copper, ammonia and sulphuric acid, or a mixture of sulphate of ammonia, and the compound of ammonia with oxide of copper. It is given in epilepsy, in a dose of half a grain twice a-day, increasing it gradually as far as the stomach or system will bear it, continuing it until the remedy has received a fair trial. It has in many cases proved successful, though in a disease arising from such various causes, and so frequently depending on derangement of organic 180 TONICS. structure, any remedy must frequently fail. It has been given in a similar manner with advantage in chorea and dysphagia. Arsenicum. Arsenic. The name arsenic, used to be appropiated to what has been ascertained to be the oxide of a peculiar metal, and in chemical nomenclature it is to this metal that the name is now applied. In its metallic state, it is of a dark gray colour; with considerable lustre; its textureis folia- ted, and it is extremely brittle. It is volatile at a heat considerably inferior to that of ignition, and when in vapour has a peculiar smell, often compared to that of garlic. At the same temperature, it is oxidated rapidly by the action of the air, forming a white vapour which condenses. At a higher temperature it burns, and af- fords the same product. This product used to be re- garded as an oxide. Being soluble however in water, capable of crystallizing, reddening the infusion of litmus, and combining with the alkalis, it has been regarded as an acid, and has been named Arsenious Acid. Though there is some foundation for this conclusion, this substance may perhaps still be ranked as an oxide; for it does not neutralize the alkaline properties, nor act on them more forcibly than many other metallic oxides; and it even neutralizes the properties of acids. By a higher degree oxygenation, it is converted into a substance of un- doubted acid powers, the arsenic acid. The oxide of arsenic, or white arsenic of commerce, is not formed from the oxygenation of the metal, but is obtained by sublimation from various metallic ores in which it exists. The sublimate is in the form of a white dense cake, which is reduced to powder, for the uses to which it is applied. In the London Pharmacopoeia, this is ordered to be prepared for medicinal use by a second sublimation. It consists of 75.2 of arsenic, and 24.8 of oxygen. Its taste is acrid and penetrating; it is soluble in 80 parts of cold, and in 15 parts of boiling water; the latter solution, on cooling, affording minute crystals. This substance has been long known as the most viru- TONICS. 181 lent of the mineral poisons. Even in a very small quan- tity, it occasions vomiting, purging, tremors, and paraly- sis; in a quantity a little larger, it excites severe pain in the stomach, extreme thirst, violent vomiting, with great anxiety and depression. The pain extends over the ab- domen, respiration becomes difficult, the, pulse is quick and irregular, the vomiting is incessant, accompanied with tremors and convulsions, and the patient dies exhausted. On dissection, the internal surface of the stomach and upper part of the intestines is found in- flamed or eroded. Though so violent in its operation, arsenic has been frequently employed in medical practice; and when pro- perly administered, we obtain from it, in certain diseases, all the advantage which is derived from the operation of the most safe and powerful tonic. This is well displayed in its efficacy in the treatment of intermittent fever, the disease in which it has been principally used. It is employed medicinally under various forms. A preparation of it introduced by Fowler and analogous to one which had been known under the name of Tasteless Ague Drop, has been adopted by the London College, and named Liquor Arsenicalis. It is prepared by dis- solving sixty-four grains of the white oxide, and the same quantity of sub-carbonate of potash, in sixteen ounces of water, adding half an ounce of compound spirit of lavender. This is given in a dose of four drops, three times a-day, and gradually increased to double that quantity; its use being occasionally intermitted, not persisted in if it does not soon prove effectual, and immediately relinquished if it occasion nausea or pur- ging. The arseniate of potash, prepared by exposing the white oxide of arsenic with an equal weight of nitre, to a heat gradually raised to redness, and crystallizing the residual mass, is another preparation which has been employed, and has been lately sanctioned by the Dublin College. It is used in the same manner, in the dose of the eighth part of a grain of the crystallized salt. Under the same forms arsenic has been used in remitting fever, 182 TONICS. in periodical headach, in dropsy, hydrophobia, lepra, and elephantiasis, and undoubtedly with safety and advan- tage, though its administration will always require to be conducted with much care. Externally, it is used in scirrhus and cancer;—applications of it which will be noticed under the class of Escharotics. The antidotes which have been employed to counter- act the poisonous operation of arsenic are various. Vo- miting, if not produced by the arsenic, which it gene- rally is, must be immediately excited, and as the sto- mach is highly irritable in such cases, the milder emetics, and especially oil, which is supposed to involve the particles of the poison, have been recommended. According to the assertion of Renault, oil appears from experiments rather to favour its action; and tepid water, or mucilaginous liquors, ought to be preferred; these too are useful in facilitating vomiting, and scarcely any thing more than this is within the power of the prac- titioner. Reliance has been placed on solutions of the alkaline sulphurets, or of sulphuretted hydrogen. The latter appears, from Renault's experiments, to have some power, since, if it were previously combined with the arsenious acid, it rendered it nearly inert; but if merely introduced into the stomach with it, or after it had been swallowed, especially if the arsenic were not dissolved, it seemed to have little efficacy as an antidote, and indeed cannot be expected to have much effect. Bismuthum. Bismuth. This metal is of a white colour, with a shade of yellow, has a foliated fracture, is brittle, very fusible, capable of being volatilized, and easily susceptible of oxidation. Though it has not been received into the Pharmacopoeias, it has a claim to a place in the Materia Medica, as its oxide, or rather sub-nitrate, has been employed with considerable advantage in Gastrodynia, Pyrosis, and other affections connected with debility of the digestive organs. This preparation is obtained by decomposing the solution of bismuth in nitric acid by TONICS. 183 the affusion of water; the sub-nitrate is precipitated, and is washed and dried. It is given in a dose from two to six grains, two grains being given twice or thrice a-day, or in more severe cases five grains being given at once. In these doses, it scarcely produces any other sensible effect than a remission of pain, and ultimately a removal of the morbid state from which this has arisen. Barytes. Terra Ponderosa. Barytes. Heavy Earth. This earth is found in nature combined with sulphu- ric acid, and with carbonic acid. The native carbonate was known to prove poisonous to animals, and this sug- gested the application of it to medicinal purposes. The form under which the barytes has been used, is in com- bination with the muriatic acid; for the preparation of which a formula has been inserted in the Edinburgh Pharmacopoeia, either by decomposing the native car- bonate by muriatic acid, or decomposing the sulphate by heating it with charcoal, and adding this acid to the solution obtained by washing the residual matter with water. The muriate is obtained by crystallization. This salt has been employed as a remedy in scrofula, in can- cer, some forms of syphilis, and in hectic fever con- nected with ulceration. Its sensible effects, where advantage has been derived from it, have been improv- ing the appetite and general strength; sometimes it occasions diaphoresis or diuresis, and in an over dose is liable to produce nausea, vertigo, tremors, and insensi- bility. Its usual dose is five drops, gradually increased to twenty or more. Its virtues have been perhaps over- rated, as it is rather falling into disuse. Calx. Lime. This earth exists abundantly in nature combined with carbonic and other acids. From the native carbo- nate it is obtained by expelling the carbonic acid by heat. It is soluble in water in small quantity; the solu- tion has a styptic taste, and is the form under which lime has been medicinally employed. It is used with advantage in dyspepsia, its beneficial effects arising JL84 TONICS. principally from its tonic and astringent quality, as in the small quantity which water can dissolve, it can have little effect by any chemical agency in obviating acidity. It is employed too as an astringent in chronic diarrhoea and in leucorrhoea. As a pure tonic, the product of the combination of it with muriatic acid, the muriate has been introduced into practice as much superior in effi- cacy to muriate of barytes, and a formula for preparing it is given by the Edinburgh and Dublin Colleges. It has been used principally in scrofula and hectic fever, and in dyspepsia. Its dose is from half a drachm to a drachm of the saturated solution; and as it is a medicine of considerable activity, it requires to be given with caution. Carbonate of lime is used as an antacid: and Phosphate of lime has from theoretical views been pro- posed as a remedy, in rickets and mollities ossium. The two following substances, though not strictly belonging to the mineral kingdom, may be associated with the preceding tonics, as connected with them by chemical relations. Acidum Nitricum. Nitric Acid. This acid is the product of the saturation of nitrogen with oxygen, and consists of 29.5 of the former, and 70.5 of the latter. It is generally obtained by decompos- ing nitrate of potash by sulphuric acid, assisted by heat. It is colourless; emits white fumes; its specific gravity is 1.504; is extremely corrosive, acts with much energy on inflammables and metals from parting with oxygen readily, and is eminently possessed of all the acid pro- perties. The tonic powers of this acid are conspicuous in sup- porting the system under the irritation of a mercurial course. As a remedy against lues venerea, it was some years ago introduced into practice, and received a very extensive trial; and the result appears to have been suf- TONICS. 185 ficiently established, that it is, to a certain extent at least, capable of counteracting the syphilitic poison. The se- condary symptoms of the disease have disappeared under its use, and the primary symptoms been completely removed. It is however inferior to mercury in the cer- tainty of its operation, but still is a valuable remedy combined with it, both as promoting its operation, and as obviating the injurious effects of mercurial irritation. With such views, it is given in a dose of from one to two drachms, this being taken largely diluted with water, in the course of the day. It is likewise adminis- tered with advantage in that chronic affection of the liver frequently arising from residence in a warm cli- mate, in dyspepsia particularly with the view of reliev- ing sickness and anorexia, and in obstinate cutaneou.*. eruptions. Oxy-murias Potassje. Oxy-muriate of Potash. This salt, which, strictly speaking, is the Hyper- oxymuriate of Potash, is prepared by introducing a cur- rent of oxy-muriatic acid gas into a solution of potash. The acid is decomposed, one portion of it yielding oxy- gen to the other; the one therefore returns to the state of muriatic acid, the other becomes hyper-oxymuriatic acid, and common muriate and hyper-oxymuriate of potash are formed, the latter separating by crystalliza- tion in brilliant white flakes. The process has been introduced into the Dublin Pharmacopoeia. As a remedy, it may be classed with the nitric acid, and it was the hypothesis of nitric acid acting medici- nally by imparting oxygen to the system, that led to its medicinal use. Its operation in checking or removing the symptoms of syphilis is similar; it also increases the force of the circulation, and excites the actions of the system. Its efficacy as an anti-venereal is considered as superior to that of the nitric acid, but it does not appear to be equally advantageous as an auxiliary to mercury. Hence, as its operation alone cannot be relied on for certainty, and as it frequently fails, it is little employed, Vol. I. 2 A 186 TONICS. while nitric acid still continues to be occasionally used. The dose in which the oxy-muriate has been given, is ten grains three or four times a-day, and increased gra- dually to twenty or twenty-five. TONICS FROM THE VEGETABLE KINGDOM. The tonic power of vegetable substances is inti- mately connected with certain sensible properties which they possess, particularly with bitterness, and the aro- matic quality. In those tonics in which these qualities are blended, they are their most distinctive properties; and in those in which either of them is predominant, we still discover a degree of tonic power, or of that stimu- lating operation on which this power depends. The vegetable products in which bitterness, without any other marked sensible medicinal quality, predomi- nates^iave always more or less of a tonic power; the stimulant operation on which this depends, seems, how- ever, to be not much extended over the system: hence they have scarcely any sensible effect in augmenting the force of the circulation, or the heat of the body, in increasing the secretions, or in stimulating to action any particular part: their operation is principally in giving vigour to the stomach, and other digestive organs, and obviating those symptoms connected with debility of these organs. Still their operation is not entirely local; they prove tonic to the general system, not only indi- rectly by their action on the stomach, but by a more direct operation. This is displayed in their power of removing diseases connected with general debility, as intermittent fever, or the different species of dropsy, particularly anasarca, which so frequently depend on diminished energy of the absorbents. The injurious consequences which sometimes arise from the use of bitters too long continued, affords another proof of their action on the general system. TONICS. 187 Bitterness in vegetables has been supposed to reside in a peculiar proximate principle, which has been named the Bitter Principle. This opinion, however, is extreme- ly vague, and rests on no sufficient evidence. The qua- lity of bitterness may reside in any of the known prin- ciples of vegetable matter: in many of the bitters of the Materia Medica, it appears to be connected with their extract, as it is obtained equally by the action of water in alkohol; it is not volatile, and in general is not much impaired by decoction. Aromatics are more rapid and diffusible in their ac- tion; they sensibly stimulate the general system, and augment the force of the circulation; but this is scarcely sufficiently permanent to admit of their being adminis- tered with advantage as tonics. They are therefore rather employed as temporary stimulants, to obviate debility of the digestive organs, or as promoting the action of bitters. Still, as strictly connected with the substances belonging to this class, I have not hesitated to place them under it. There is one general virtue they possess, and for which they are often used, that of preventing or re- lieving nausea;vhis they do partly from their agreeable taste and odour, and partly probably from their stimulant operation on the> stomach. The aromatic quality in ge- neral resides in their essential oil; hence it is communi- cated both to water and alkohol by infusion: their oils are usually pungent and stimulant, and their distilled waters and spirits partake of these powers. From the qualities which bitters and aromatics pos- sess, the stimulant operation of the one being slow and permanent, that of the other being more diffusible and transient, it might be inferred perhaps, that their com- bination will afford a superiority of tonic power. In the most powerful vegetable tonics, accordingly, these qua- lities are generally blended; these may be placed first, and from them there is a series to the more pure bitters and aromatics. 188 TONICS. Cinchona Officinalis. Cortex Peruvianus. Cinchona. Peruvian Bark. Pentand. Monogyn. Contorte. Cortex. Peru. The natural history of the genus Cinchona has been but imperfectly elucidated, and hence the Edinburgh College have inserted in their catalogue of the articles of the Materia Medica, the three kinds of Peruvian bark at present met with in the shops, the Pale, the Red, and the Yellow, leaving undetermined their natural distinc- tions. The species of this genus, it now appears, are numerous, and many of them natives of Peru; and it is not improbable that all, or the greater number of these contribute to furnish the Peruvian bark of commerce. The London College have inserted three species, Cin- chona Lancifolia, Cinchona Cordifolia, and Cinchona. Oblongifolia; the first, according to Dr. Powel, fur- nishing the pale bark, the second the yellow, and the third the red. These barks appear to be procured and prepared in a similar manner. The bark is stripped from the trunk and branches; it is dried by exposure to the sun, and after being imported into Europe, is s'"V-d by separating the finer from the coarser. The pale bark is in the form of small quilled twigs, thin, breaking close and smooth, friable between the teeth, covered with a rough coat of a grayish brown colour, internally smooth, and of a light brown; when thick and not convoluted, it is considered as of inferior quality; its taste is bitter, and slightly astringent; its fla- vour slightly aromatic, with some degree of mustiness. The Red is in large thick pieces, usually flat, though sometimes quilled, externally covered with a brown rugged coat, internally more smooth and compact, but fibrous, of a dark red colour; its taste and smell are similar to those of the pale, but the taste is rather stronger. The Yellow, so named because it approaches more to that colour than either of the others do, is the variety last introduced. It is in flat pieces, not convoluted like TONICS. 189 the pale, nor dark-coloured like the red; externally ■ smooth, internally of a light cinnamon colour, friable and fibrous; it has no peculiar odour different from the others, but a taste incomparably more bitter, with some degree of astringency. Cinchona has often been subjected to chemical exa- mination, bHt its constituent proximate principles are still not well determined. This indeed appears to be attended with peculiar difficulties, from the different species containing different principles, and from the nature of some of these being not well ascertained. The basis of all of them is the ligneous fibre, consti- tuting the greater part of their weight, but to this are attached various principles capable of being extracted by different solvents. Cold water infused on pale bark for some hours, acquires a bitter taste, with some share of its odour; when assisted by a moderate heat, the water takes up more of the active matter; this infusion is transparent while warm, but as it cools becomes slightly turbid; by decoction, a fluid, deep coloured, of a bitter styptic taste, is obtained, which, when cold, de- posites a precipitate soluble in alkohol. By long decoc- tion, the virtues of the bark are nearly impaired or de- stroyed, owing to the chemical change and precipitation of its active matter. Alkohol is a more powerful solvent of its active principles than water, the tincture being of a much deeper colour and stronger taste, and holding more matter dissolved. Brandy and other spirits and wines afford also strong solutions in proportion to the quantity of alkohol they contain. A saturated solution of ammonia is also a powerful solvent; vinegar is less so even than water. By distillation, water is slightly im- pregnated with the flavour of bark; but it is doubtful whether any essential oil can be obtained. The action of menstrua on the red bark is nearly the same, the solutions only being stronger, or containing a larger quantity of the matter which is precipitated from the decoction as it cools, and which is more peculiarly soluble in alkohol, this matter being apparently com- 190 TONICS. posed of the principles in which the activity of the bark resides. The analysis of the yellow bark shows that its active principles are more powerful than in either of the others, as it affords to water, alkohol, &c. tinctures much stronger both in bitterness and astringency, especially in the former quality. It is not easy to determine from these results, the na- ture of the principles extracted, or what relation they have to the powers of the bark. As the active matter appears to be more soluble in hot than in cold water, being partially precipitated from the former as it cools, and as it is still more soluble in alkohol, it might be con- cluded to be of a resinous nature. Being soluble to a certain extent, however, in water, and suffering at least a partial decomposition when boiled under exposure to the air, it may also be considered as approaching in its characters to extract. Besides this, from the effects of re-agents, Peruvian bark has been considered as containing a quantity of astringent matter, and this matter appears to have some relation to the matter extracted by water with the aid of heat, and by alkohol. On adding a solution of sul- phate of iron to the infusion, a deep colour is struck, not purple indeed like that usually produced by the ac- tion of that test in the vegetable astringents, but rather of a dark olive green; the same colour is still deeper when the salt is added to the decoction, or the tincture. This was regarded as a proof of the presence of the as- tringent principle or tannin, and hence it might be in- ferred, that a precipitate would be produced by the addition of gelatin. This accordingly happens with some kinds of Peruvian bark; a solution of gelatin added to the infusion giving a precipitate more or less copious. But the singular fact has been discovered, that there are other varieties which do not precipitate gelatin, but have the opposite property of giving a precipitate with tannin, or at least with infusion of oak bark, or infusion of galls. This latter phenomenon, Seguin considered absurdly as TONICS. 191 depending on the presence of gelatin, and pretended that gelatin exerted the specific power of Peruvian bark on the system, so that with animal glue he had cured inter- mittent fever. Dr. Duncan inferred, that the phenomenon is owing to the presence of a peculiar proximate prin- ciple of vegetable matter not before observed, to which he has given the name of Cinchonin. Vauquelin, in his analysis of the different species of Peruvian bark, found generally, that their aqueous infusion gave a precipitate both with tannin and gelatin; some, however, gave no sensible precipitate with gelatin, while they precipitated tannin. Among these, he ranks the common pale bark. Others again did not precipitate tannin, but formed a precipitate with gelatin. His observations, however, are of less value, as although deduced from experiments on seventeen species, as he calls them, of cinchona, these are not distinguished by their specific characters, and we therefore scarcely know to what the observations ap- ply. From the intermixture of different kinds of Peru- vian bark in commerce, and the uncertainty of their uniformity, it is not easy to determine what species more peculiarly afford this principle. I have found, that the watery infusion of the pale bark is not sensibly pre- cipitated either by gelatin or tannin; that of the red bark is not precipitated by gelatin, but gives a copious preci- pitate with tannin; and that of the yellow is rendered turbid by gelatin, and precipitated copiously by tannin. There is a difficulty in determining the nature of the principles on which these phenomena depend,—either that which gives a precipitate with gelatin, or is preci- pitated by tannin, if these differ from each other. Neither is it very apparent what relation they have to the matter in which the active powers reside; it may be concluded, however, that they are not essential to it, since they are not found in pale bark, and since they are not uniform in the other species in any relation to the medicinal qua- lities. The same facts prove, that they have no relation to the resino-extractive matter, the principle probably of greatest activity of any which bark contains. 192 TONICS. The infusions of some varieties of bark redden the more delicate vegetable infusions, and Vauquelin has discovered, in the matter extracted by water with the aid of heat, a salt composed of lime, with a peculiar crystallizable acid, which he has named Kinic Acid. The active matter of bark is rendered more soluble in water by acids, a circumstance of some importance in its pharmaceutic preparation. The alkalis also add to its solubility; and some of the earths, particularly lime and magnesia, have the same effect. The comparative medicinal activity of the different kinds of Peruvian bark is not easily determined, owing to the variable state in which they are found in the shops. The red, at its first introduction, was represented as much superior in efficacy to the pale, and this appeared to be confirmed by chemical experiments on the propor- tion of active matter in it to that of the ligneous fibre; but there is some reason to doubt of this superiority with regard to the red bark now frequently met with. The yellow bark has a much greater degree of bitter- ness, and some clinical observations appeared to esta- blish its superior medicinal power. Even if this be admitted, its intense bitterness renders it unpleasant, and liable to occasion nausea. The effects of Peruvian bark are those of a powerful and permanent tonic, so slow in its operation as to be scarcely perceptible by any alteration in the state of the pulse, or of the temperature of the body. Its tonic power is inferred, therefore, principally from obviating states of debility; and it is one of those medicines, the efficacy of which, in removing disease, is much greater than could be expected, a priori, from its effects on the sys- tem in a healthy state. The only effects arising from too large a dose are nausea and headach. Intermittent fever is the disease for the cure of which bark was introduced into practice, and there is still no remedy which equals it in power,—a superiority of which, from its known operation, it is difficult to give any explanation. Little diversity of opinion now exists TONICS. 193 with regard to the rules regulating its administration. It is given freely in the earliest stage of the disease, and without any previous preparation, farther than the exhi- bition of an emetic to evacuate the stomach. And it may be employed with safety and advantage in every period of the fever. It has been supposed rather more effectual when given before the recurrence of the paroxysm, and that from this mode of employing it, less is required for the cure. The usual practice, however, is to give it in doses of a scruple or half a drachm every fifth or sixth hour during the interval of the paroxysm; and it may be given with safety during the hot fit, being then only more apt to excite nausea. It requires to be given for some time, and continued after the fever has been re- moved, in order to prevent a relapse. In remittent fever it is given with equal freedom, even though the remission of the fever may be obscure, and frequently with advantage. In those forms of continued fever which are connected with debility, as in typhus, cynanche maligna, and con- fluent small-pox, &c. bark has been regarded as one of the most valuable remedies. It is difficult, however, to give it in such quantities as to obtain much sensible effect from it, as from the weakened state of the organs of digestion, it remains in the stomach unaltered, and is liable to produce nausea and irritation. In modern prac- tice, therefore, bark is less employed in typhus, pre- ference being given to the more powerful exciting operation of opium and wine. It has been regarded as hurtful even in those forms of fever, where the brain or its membranes are inflamed, or where there is much irritation, marked by subsultus tendinum, and convul- sive motions of the extremities. Advantage is some- times derived from it in the convalescent stage of the disease. Even in fevers of an opposite type, where there are marks of inflammatory action, particularly in acute rheu- matism, bark has been found useful, blood-letting being generally previously employed. Vol. I. • 2B 194 TONICS. In erysipelas, in gangrene, in extensive suppuration, and in scrofulous and venereal ulceration, the free use of bark is of the greatest advantage. In the various forms of passive hasmorrhagy, in many other diseases of chronic debility, dyspepsia, hypochon- driasis, paralysis, rickets, scrofula, dropsy, and in a variety of spasmodic affections, epilepsy, chorea, and hysteria, cinchona is administered as a powerful and permanent tonic, either alone, or combined with other remedies suited to the particular case. The more com- mon combinations of it are with sulphuric acid as an astringent, with preparations of iron as a tonic, with mercury in syphilis, in spasmodic diseases with valerian, and with cicuta in scrofula, and extensive ulceration. Its usual dose is half a drachm. The only inconve- nience of a larger dose is its sitting uneasy on the sto- mach. It may, therefore, if necessary, be frequently re- peated, and in urgent cases may be taken to the extent of an ounce or even two ounces, in twenty-four hours, though from such large doses probably no adequate advantage is derived. The powder is more effectual than any of the prepa- rations; it is given in wine, in any spiritous liquor, or, if it excite nausea, combined with an aromatic. The cold infusion is the least powerful preparation, but is grateful and sits easy on the stomach; it is however so weak, that it is scarcely used but as a bitter in dys- pepsia. Prepared by previous trituration of the bark with a little magnesia, it is rather more active. The de- coction contains more of the active matter of the bark, and is the preparation generally used when the powder is rejected; its dose is from 2 to 4 ounces; but even it cannot be relied on for any important effect. The spi- ritous tincture, though containing more of the active principles, cannot be extensively used on account of the menstruum, but is principally employed, occasionally and in small doses, of 2 or 3 drachms, as a stomachic. The extract is a preparation of some power, when pro- perly prepared by the joint action of alkohol and water; TONICS. 195 but as this is expensive, the watery extract only is usu- ally found in the shops, and it is very variable in strength. It is given in the form of pill, in a dose from 5 to 15 grains, and affords the best form for combining bark with iron. Bark is likewise sometimes given in the form of ene- ma; 1 scruple of the extract, or 2 drachms of the powder, being diffused in 4 ounces of starch mucilage. The de- coction is sometimes applied as a fomentation to ill-con- ditioned ulcers, or the powder is sprinkled on the ulce- rated surface. Offic. Prep.—Decoct. Cinch. Extr. Cinch. Inf. Cinch. Tinct. Cinch. Ed.—T. Cinch. C. Lond. Dub. Cinchona Carib^ea. Caribaean Bark. This species, belonging to the same genus, a native of the Caribee Islands, has been proposed as a substitute for Peruvian bark, and has as such been received into the Edinburgh Pharmacopoeia. It is more bitter, and less aromatic, is of a brown colour, somewhat convo- luted and fibrous. According to the observations of Dr. Wright, who employed it in Jamaica, its effects are similar to those of the officinal cinchona. The Cinchona Floribunda, or St. Lucia bark, has been also some- times used. It is of a darker brown colour; its taste is sweetish, but becomes extremely bitter. It has been found more liable than the other species to produce nausea and purging. Aristolochia serpentaria. Sei'pentaria Virginiana. Virginian Snake-root. Gynand. Hexand. Sarmentose. Radix. Virginia, Ca- rolina. This root consists of a number of small fibres, issu- ing from one head, of a grayish brown colour; it has a slightly aromatic smell, and a warm bitterish taste. Its active matter is extracted partially by water, and by alko- hol; entirely by proof spirit. By distillation, it affords a small quantity of an essential oil, somewhat fragrant, but not pungent. 196 TONICS. Serpentaria is a stimulating aromatic tonic, which used formerly to be much employed in fevers of the typhoid type, to support the powers of the system. It was given in a dose of from 10 to 20 grains every fourth or fifth hour; with this intention, it is now, how- ever, very rarely prescribed, and in any tonic power it possesses is probably considerably inferior to cinchona. It is sometimes combined with cinchona in the treat- ment of intermittent fever, and occasionally enters as an ingredient into the composition of bitter infusions and tinctures used in dyspepsia.* Offic. Prep.—T. Arist. Serpent. Ed. L. D. UoRSTENrA contrayerva. Contrayerva. Tetrand. Monog. Sea. bride. Radix. Peru, West Indies. This root is in small twisted fibres, of a yellowish colour; has an aromatic smell, and a bitterish taste; yields its active matter to water and alkohol. Contrayer- va, like serpentaria, was formerly used as a stimulant in * The serpentaria is certainly a much more important article than it is here represented to be. Whether alone, it is adequate to the cure of confirmed ague and fever, I am not prepared to say. But in combination with Peruvian bark, it proves a useful auxiliary to that medicine, and enables the stomach in many instances to bear it, when otherwise it would be rejected. To remittent fever it is still better adapted, being often prefera- ble even to the bark, inasmuch as it is rarely offensive to the sto- mach, and may be given, without injury, in those obscure states of the disease, where the remission is not readily discernible. As a remedy in the secondary stages of pneumonia, and in catar- rhal and other winter affections, this species of snake-root has long had an indisputable reputation. It is always employed under these circumstances in infusion with a view of exciting perspira- tion, which it rarely fails to do, and of course, of affording more or less relief. Many diseases might be added, in which it is prescribed with great advantage; but such a detail would be superfluous as, perhaps, the powers of no medicine are more accurately understood by American practitioners. I shall, therefore, only further remark, that it has been found eminently beneficial in checking bilious and other vomitings, and hence, most probably, its great efficacy in that form of pneumonia which is properly enough denominated bilious pleurisy.—Ed. TONICS. 197 typhoid fever, in a dose from 5 to 20 grains, but like it too has fallen into disuse. Mixed with carbonate of lime, it forms the compound powder of contrayerva of the London Pharmacopoeia, which is used as a remedy in diarrhoea. Offic. Prep.—P. Contrayerv. C. Lond. Croton eleutheria. Cascarilla Monoec. Monadelph. Tricocca. Cortex. Bahama Islands, North America. Cascarilla bark is in small quills of a gray colour; has a slightly aromatic smell, and a warm bitter taste; it is highly inflammable. It has been used as a substi- tute for the Peruvian bark, and has been employed too as a remedy in dysentery, and in obstinate diarrhoea. Its usual dose is a scruple or half a drachm, but in modern practice it is little used. Offic. Prep.—Infus. Case. Tinct. Case. Lond.— Extr. Case. Resin. Dub. Cusparia febrifuga. Angustura. Pentand. Monogyn. South America. This bark was imported a few years ago from the Spanish West Indies, the botanical characters of the tree producing it being unknown. These have been lately determined by Humboldt, and the London Col- lege have adopted the name Cusparia Febrifuga, by which they distinguish it. It is in flat pieces, externally gray and wrinkled, internally of a yellowish-brown co- lour, and smooth; it has little odour; its taste is bitter and slightly aromatic. Water, assisted by heat, takes up the greater part of its active matter, which does not seem to be injured by decoction. Alkohol dissolves its bitter and aromatic parts, but precipitates the extractive mat- ter dissolved by water, and its solution is on the con- trary decomposed by water. Proof spirit appears to be its proper menstruum. By distillation, it affords a small quantity of essential oil. The bark triturated with lime or potash, and water, gives a smell of ammonia. Angustura is a powerful antiseptic. It was originally 198 TONICS. introduced in the West Indies as a remedy in fevers, equal or even superior to the Peruvian bark. In this country it has not been much employed as a substitute for cinchona; and in the treatment of intermittent, it has in the trials that have been made of it failed. It has been used principally in obstinate diarrhoea, and in chronic dysentery, or as a remedy in dyspepsia. Its dose is from 10 to 20 grains of the powder, or one drachm in infu- sion or decoction. Its tincture with proof spirit is given in a dose of one or two drachms. Offic. Prep.—Infus. Cuspar. Lond.—Tinct. Angust. Ph. Dub. Swietenia febrifuga. Swietenia. Decand. Monogyn. Trihilate. Cortex. East Indies. The bark of the wood of this tree is of a red colour internally; externally it is covered with a gray epider- mis; it has an astringent bitter taste; it yields its active matter to water, by infusion or decoction, and by evapo- ration an extract is obtained, highly astringent. It was introduced as a substitute for Peruvian bark, and in In- dia has been used as such with advantage. Its dose in substance is half a drachm. Swietenia mahagoni. Mahogany. Cortex. Spanish America, West Indies. This species, of the same genus as the preceding, has similar qualities and virtues, being equally bitter and astringent. It has therefore been received into the Edinburgh Pharmacopoeia, and may be employed to answer similar indications. Colomba. (Calumba, Pharm. Lond.) Colomba. Of the plant which furnishes this root, no botanical account has been obtained. It has been said to be brought from Ceylon; but from later accounts, it appears to be the produce of Southern Africa.* It is in round * Not long ago a plant, which is commonly considered as a spe- cies of Colomba, but which is more probably a species of Gentian, TONICS. 199 thin pieces, evidently formed by transverse sections of the root; the circumference of these is covered with a bark; the woody part is of a light yellow colour. It has an aromatic smell, and a bitter taste. It yields its bitter- ness to water; but proof spirit is its proper menstruum, though the tincture is not very strong. Colomba is a powerful antiseptic and bitter; it is used with much advantage in affections of the stomach and intestinal canal, accompanied with redundance of bile; it is also employed in dyspepsia, and forms a more powerful and grateful stomachic than the common bit- ters. Its dose is half a drachm of the powder, which in urgent cases may be repeated every third or fourth hour. Offic. Prep.—Tinct. Colomb. Ed. Lond. Dub.— Infus. Colomb. Lond. Quassia Simarouba. Simarouba. Decand. Monogyn. Gruinales. Cortex. South America. The bark of the root of this tree, which is the part medicinally employed, is in long pieces, of a fibrous texture and yellowish colour; destitute of odour, and having a strong bitter taste. It is however very variable in its sensible qualities, some having scarcely any bit- terness. Water and alkohol dissolve its active matter; the solution in either suffers no change from sulphate of iron. Simarouba has been celebrated as a remedy in inter- mittent fever, dysentery and chronic diarrhoea, and has been given generally in the form of decoction: in sub- stance the dose is one scruple. Though used in the countries of which it is a native, it is with us rarely pre- was discovered in the vicinity of Marietta in the state of Ohio. It appears from the most authentic accounts which we have had of it, to be a perennial plant, luxuriant and well proportioned, attain- ing to the height of eight or ten feet. I have heard it described as superior to the imported Colomba. But of this I am not altogether persuaded, as the specimens which 1 have seen of it seemed to pos- sess much less of the bitter principle. To the botanist it is known by the title of Frasera Corolinensis, and by the people of the country it is called the Marietta Colomba.—Ed. * 200 TONICS. scribed. An infusion of it has a place in the London Pharmacopoeia. Offic. Prep.—Infus. Simaroub. Ph.%Lvnd. Quassia Excelsa. Quassia. Decand. Monogyn. Gruinales. Lig- num. West Indies. The wood of the root of this tree is of a yellowish white colour; it has a taste intensely bitter, without any odour or aromatic flavour. The bitterness is extracted equally by water and by alkohol. It is used as a remedy in dyspepsia, diarrhoea, and in remittent and intermittent fevers, and is also sometimes employed to check vomiting. It is commonly given un- der the form of the watery infusion; in substance, in which state it has been employed in the treatment of intermittents; its dose is from ten to thirty grains. Offic. Prep.— Infus. Quass. Ph. Lond.—Tinct. Quass. Ph. Dub. Gentiana Lutea. Gentian. Pentand. Digyn. Rotacee. Radix. Switzerland, Germany. This root is in long slender pieces, soft and flexible, of a yellowish colour, with a grayish epidermis. It has a very bitter taste, without any peculiar flavour. This bitterness is extracted both by water and alkohol. Dilu- ted alkohol is its proper solvent. Gentian is a common remedy in dyspepsia, in the form of infusion or tincture; and as a bitter, usually forms the basis of stomachic remedies. In substance, it has been used, though much more rarely, for the cure of intermittents, in a dose of half a drachm. Offic. Prep.—Extr. Gent. Lut. Inf. Gent. C. T. Gent. C. Ph. Ed. Lond. Dub__-Vin. Gent. C. Ed. Anthemis nobilis. Chamaemelum. Chamomile. Syngenes. Poly- gam, superfl Composite. Flores. Indigenous. There are two varieties of these flowers obtained by cultivation, the single and double flowered: the former is much stronger, the odour and taste residing not in TONICS. 201 the white petals, but in the disk or tubular florets. Both have a bitter nauseous taste, and a strong unpleasant odour. The bitterness, with part of the odour, is ex- tracted by water and alkohol, and if the infusion has been made with warm water, it is nauseous. Distilled with water, they yield a small quantity of essential oil. Chamomile is a powerful bitter, and as such is useful in dyspepsia, forming a popular remedy which is in common use. When employed for this purpose, it ought to be under the form of the cold infusion, which is most grateful. The infusion in tepid water, when strong, acts as an emetic, and is often used to promote the action of other emetics. In substance, it has been given as a remedy in intermittent fever, in a dose of half a drachm three or four times a-day. Externally, the flowers steeped in water are employed as a fomentation. The extract, which is intensely bitter, is a convenient vehicle for forming pills, especially when it coincides in virtue with the substance prescribed under that form. Offic. Prep.—Extr. Anth. N. Edin. Dub. Lond.— Inf. Anth! Ol. Anth. Lond.—Decoct. Anthem. Ed. Dub. The following plants, possessing bitterness in a greater or less degree, were formerly much employed, but are now discarded from practice. They possess no virtues but those of bitters, and as they have all more or less of a nauseous flavour, gentian, colomba or quassia is preferred to them. It is necessary to notice only their botanical characters. Artemisia absinthium. Wormwood. Syngenes. Polygam. su- perfl. Composite. Herba. Indigenous. Chironia centaurium. Centaury. Pentand. Monogyn. Rotacee. Herba* * Of the centaury, we have a species, the Chironia Angularis of Linnaeus, which I have reason to believe is, in every respect, a very superior medicine to that which we derive from Europe. It is a very beautiful plant, growing abundantly in many sections of the Vol. I. 2C 202 TONICS. Marrubium vulgare. Hoarhound. Didynam. Gijnmotperm. Ver- ticil late. Herba. Mentanthes trifoliata. Trefoil. Pentand. Monog. Rotacee. Herba. Centaurea benedicta. Blessed Thistle. Syngenes. Polygam. frustran. Composite* Herba. Spain. The remaining substances belonging to this class arc those in which the aromatic quality predominates, blended in some of them with a degree of bitterness. Citrus aurantium Orange. Polyadelph. Icosand. Pomacee. Cor- tex flavus Fructus; Fructus; Fructus immaturus. India. Though a native of India, this fruit is abundantly cultivated in the south of Europe. The outer rind of the fruit has a grateful aromatic flavour, and a warm bitterish taste. It is dried for use; both taste and flavour are extracted by water by infusion, as well as by alko- hol; and by distillation a small quantity of essential oil is obtained. Its qualities are those of an aromatic and bitter. It has been employed to restore the tone of the stomach; and it is a very common addition to combi- nations of bitters used in dyspepsia, communicating to them its grateful odour, and coinciding with them in power. It has likewise been given in intermittents in a dose of a drachm twice or thrice a-day. United States, and affords a pure bitter, with some slight aromatic flavour, which renders it rather pleasant to the taste and grateful to the stomach. As a remedy, it is very extensively employed in our remittent and intermittent fevers, and with great success. It may be exhi- bited during the remission or intermission, or in any stage of the paroxysm, and therefore in some instances is preferable to the Peruvian bark The usual mode of prescribing it is in strong infu- sion, of which copious draughts are directed to be repeatedly ta- ken.—Ed. TONICS. 203 Offic. Prep.—Aq. Citri Aur. Cons. Citr. Aur. Syr. Citr. Aur. Ed.—T. Cort. Aur. Lond. Dub.—Inf. Citr. Aur. Lond. The unripe fruit, Aurantia Curasslaventia, Curassoa Oranges as they are named, retain when dried the aro- matic flavour of the peel, with rather a larger share of bitterness, and are applied to the same uses. The juice of the ripe fruit consists principally of acid and saccha- rine matter, and so far as it has any medicinal virtue is a refrigerant. Citrus medica. Lemon. Polyadelph. Icosand. Pomacee. Cortex fructus. Asia. The exterior rind of the fruit of the lemon is similar in flavour and taste to that of the orange, but is rather less bitter and aromatic; its flavour too is more perish- able, and from both circumstances it is less frequently used, though it may be employed for similar purposes. The juice is strongly acid, consisting chiefly of citric acid; its medicinal applications fall to be considered under the class of refrigerants. Offic. Prep.—Aq. Citr. Med.—Syr. Citr. Med. Ed. —Acid. Citric. Pharm. Lond. Laurus cinnamomum. Cinnamon. Enneand. Monogyn. Qleracea. Cortex. Ceylon. This tree, a native of Ceylon, is now cultivated in India. The cinnamon is the interior bark of the branches of the tree; it is thin and much convoluted, of a texture somewhat fibrous, friable, of a light brown colour, hav- ing an agreeable pungent taste, with a degree of sweet- ness, and a grateful aromatic flavour. Its virtues chiefly depend on a small quantity of essential oil which it con- tains, and which, when obtained by distillation, is highly odorous and pungent. Cinnamon is the most grateful of the aromatics. It is used to cover the unpleasant taste and flavour of other medicines, and to reconcile them to the stomach. It is 204 TOXICS. also employed by itself as a moderate stimulant, given generally under the form of the watery infusion or distil- led water. The former is more grateful, and is often successful in relieving nausea and checking vomiting. Offic. Prep.—Aq. L. Cinn. Sp. L. Cinn. T. L. Cinn. T. L. Cinn. C. Pulv. Cinn. Comp. Ed. Lond. Dub. Laurus cassia. Cassia. Enneand. Monogyn. Oleracee. Cortex. Flores nondum expliciti. India. Th e Cassia Bark resembles that of cinnamon in ap- pearance, taste and flavour; but is distinguished by its taste being more pungent, less sweet, and more mucila- ginous than that of the real cinnamon; by its texture being denser, or less shivery, so that it breaks close and smooth, and by the pieces of it being thicker and less convoluted. Its aromatic quality, like that of cinnamon, resides in an essential oil. It affords a distilled water, stronger than that of the genuine cinnamon, and yields also its taste and flavour to water by infusion. It is used for the same purposes as cinnamon; it is, however, much less agreeable to the stomach, and rather more pungent and stimulating. It cannot, therefore, be always with propriety substituted for the other, especially where the stomach is in an irritable state. The Cassia buds dried, are similar in taste and flavour to the bark, and are often substituted for it in officinal preparations. Offic. Prep.—Aq. L. Cass. Ed. Canella alba. Dodecand. Monogyn. Oleracee. Cortex. West Indies. This is the inner bark of the branches of the tree. It is in quills or flat pieces, of a light grayish colour; its flavour is somewhat aromatic, and its taste is pungent. By distillation it affords a thick essential oil. Canella is employed principally on account of its aro- matic quality, and generally in combination with other remedies to render them more grateful. It thus enters into the composition of several officinal tinctures, and TONICS. 205 has been supposed, in particular, well adapted to cover the flavour of aloes. Offic. Prep.—V. Aloes cum Canella. Ph. Ed. Pulv. Aloes cum Canella. Ph. Dub. Mvristica moschata. Monoec. Monand. Oleracee. Fructus nu- cleus, Nux Moschata dictus; Macis; Hujus Oleum Jixum. India. Under the officinal name Myristica, are compre- hended Nux Moschata or Nutmeg, and Macis or Mace; the former being the seed or kernel of the fruit, the lat- ter the covering with which it is immediately sur- rounded. The tree is a native of the Molucca islands. The external covering and pulp of the fruit are remo- ved, and the nutmeg and mace are dried by exposure to the sun. Nutmegs are round, of a grayish colour, streaked with brown lines, slightly unctuous; they have a strong aromatic flavour, and a pungent taste. They yield their active matter entirely to alkohol: distilled with water, they afford a fragrant and pungent essential oil; by ex- pression, a sebaceous oil is obtained from them, retain- ing their fragrant odour, and part of their pungency. Nutmeg is used in medicine as a grateful aromatic. It may be given in a dose from five to fifteen grains, and is sometimes employed to relieve nausea or vomiting, or to check diarrhoea, taken generally in wine. It has been said to prove narcotic in a large dose. It is also frequently employed to conceal the taste and flavour of unpleasant medicines, and to obviate the nausea they might excite. Mace is a membranous substance, unctuous, of an orange yellow colour, and having, a flavour and taste similar to the nutmeg, but rather less strong. It is used for the same purposes. The expressed oil of nutmeg, which is generally known by the name of Oil of Mace, derives its smell and taste from the essential oil mixed with it. It is sometimes used as an external stimulating application, but in the shops is seldom found genuine. 206 TONICS. Offic. Prep.—Ol. Myrist. Mosch. Sp. Myrist. Mosch.—Ed. Lond. Dub. Eugenia caryophyllata. Caryophyllus Aromaticus. Clove. Po- lyand. Monog. Hesperidee. Flores cum pericarpio immaturo. India. The tree producing cloves is a native of the Molucca islands, and is cultivated in other parts of India. The cloves are the unexpanded flowers, which are dried by fumigating them, and exposing them to the sun. They are somewhat round, the division of the petals of the corolla being perceptible, of a grayish brown colour, slightly unctuous; they have a strong aromatic odour, and a pungent taste. They afford to water their flavour principally; to alkohol their taste. By distillation with water, they yield a fragrant essential oil, not very pun- gent. The oil of cloves commonly met with is rendered acrid by a portion of the resinous extract obtained by the action of alkohol being dissolved in it. Cloves are among the most stimulating of the aro- matics. They are employed principally as adjuvants or corrigents to other medicines. The essential oil is used with the same intention, and likewise as a local applica- tion to toothach. The infusion in tepid water has been employed as a grateful stimulant to relieve the sense of coldness in the stomach, which attends some forms of dyspepsia. Offic. Prep.—Infus. Caryoph. Pharm. Lond.—01. Caryoph. hr.—Ph. Ed. Capsicum annuum. Capsicum. Guinea Pepper, or Capsicum. Pentand. Monog. Solanacee. Fructus. East and West Indies. The fruit of this plant is an oblong pod, of an orange colour, containing a pulp inclosing seeds. The mem- branous pod has an odour aromatic and penetrating, but which is impaired by drying; its taste is extremely hot and acrid, the sensation which it excites remaining long impressed on the palate. Its pungency is completely extracted by alkohol, and partially by water. TONICS. 207 Capsicum is a very powerful stimulant. As such, it has been given in atonic gout, in palsy and dyspepsia, and in the latter stage of fever where the powers of life are nearly exhausted. It is also used as a condiment to food, especially in warm climates, and proves useful by obviating flatulence and promoting digestion. An infu- sion of it in vinegar, with the addition of salt, has been used as a gargle in cynanche; but the practice, though it has been successful in the West Indies, it is not without danger from the inflammation it is liable to induce. The seeds have been found useful in obstinate intermittents, two grains being given at the approach of the cold paroxysm. The dose of the pod is from 5 to 10 grains. Offic. Prep.—Tinct. Capsici. Ph. Lond. Piper nigrum. Black Pepper. Diand. Trigyn. Piperita. Fruct. India. Black or common Culinary Pepper is the unripe fruit of this plant dried in the sun. Its smell is aromatic; its taste pungent. Both taste and smell are extracted by water, and partially by alkohol. The essential oil, ob- tained by distillation, has little or no pungency. Pepper, from its stimulating and aromatic quality, is employed as a condiment to promote digestion: as a medicine it is given to relieve nausea, or check vomiting, to remove singultus, and as a stimulant in retrocedent gout, and paralysis. Its dose is 10 to 15 grains. Its infu- sion has been used as a gargle in relaxation of the uvula. White pepper is the ripe berries of the same plant, freed from the outer covering, and dried in the sun. It is less pungent than the black. Piper longum. Long Pepper. Diand. Trigyn. Piperite. Fructus. East Indies. This is the berry of the plant, gathered before it is fully ripened, and dried in the sun. It is oblong, indented on the surface, of a dark gray colour. In flavour, taste and other qualities, it is similar to the black pepper and may be used for the same purposes. 208 TONICS. Piper cubeba. Cubebs. Diand. Trigyn. Piperite. Fructus. East Indies. Cubebs are the dried fruit of this tree. They have an aromatic odour, and moderately warm taste. Their virtues are similar to those of the other peppers, and being rather weaker, they are little used. Myrtus pimenta. Piper Jamaicensis. Jamaica Pepper. Icosand. Monog. Hesperidee. Bacce. West Indies. The berries of this tree are collected before they are ripe, and are dried in the sun. Their taste, though pun- gent, is much less so than that of the peppers; their fla- vour is fragrant, and has often been compared to that of a mixture of cloves, nutmeg, and cinnamon. The flavour resides in an essential oil; the pungency in a resin. Pi- mento is used in medicine merely as an aromatic, and principally on account of its flavour. Offic. Prep.—Aq. Myrt. Pirn. Ol. Vol. Myrt. Pirn. Sp. Myrt. Pirn. Ph. Ed. Lond. Dub. Amomum Zedoaria. Zedoaria. Zedoary. Monand. Monog. Scita- minee. Radix. India. This root is in oblong pieces, of an ash colour; its smell is aromatic; its taste pungent and bitterish. It contains a portion of camphor along with its essential oil. Its virtues are merely those of an aromatic, and as it is rather weak, it is little used. Amomum Zingiber. Ginger. Monand. Monog. Scitaminee. Radix. India. This plant is cultivated in the West Indies, whence the dried root is imported. It is in small wrinkled pieces, of a grayish white colour, having an aromatic odour, and a very pungent, somewhat acrid taste. The Black Ginger is the root prepared with less care than the White; the latter, previous to the drying, being scraped and washed. Ginger yields its active matter completely to alkohol, and in a great measure to water. By distillation it affords TONICS. 209 a small quantity of essential oil, which is fragrant, but not pungent, the pungency residing in a resino-ex- tractive matter. This root is frequently employed as a grateful and moderately powerful aromatic, either in combination with other remedies, to promote their efficacy or,*pb- viate symptoms arising from their operation, or by itself as a stimulant. With the latter intention, it is used in dyspepsia, flatulence and tympanitis. Its dose may be 10 grains. Offic. Prep.—Syrup. Amom. Zingib. Ph. Ed. Lond. Dub.—Tinct. Zingib. P. Lond. Dub. Amomum repens. Amomum Cardamomum. Cardamomum minus. Lesser Cardamom. Monand. Monogyn. Scitaminee. Semen. India. It was always somewhat uncertain, from which of the above species these seeds are obtained, and more lately, from a more accurate description of the plant, it has been entirely removed from the genus amomum, and placed under a new genus named Elettaria, the name chosen for the species being Elettaria Cardamo- mum. This has been admitted by the London College. The seeds are dried, and imported in their capsules, by which their flavour is better preserved. Their smell is aromatic, their taste pungent, and both are commu- nicated by infusion to water, as well as to alkohol. They afford by distillation an essential oil. They are used merely as grateful aromatics, and are frequently com- bined with bitters. Offic. Prep.—Tinct. Amom. R. Ed. Lond. Dub.— Tinct. Cardom. Comp. Lond. Dub. Carum carui. Caraway. Pentand. Digyn. Umbellate. Semen. Indigenous. Caraway Seeds have an aromatic flavour, and a warm taste, depending principally on an essential oil, which they contain in considerable quantity. They are used to relieve flatulence, one or two drachms beine Vol. I. 2D 210 TONICS. swallowed entire; their essential oil, which has consider rable pungency, and is grateful, is not unfrequently added to other medicines, to obviate nausea or griping. Offic. Prep.—Sp. Car. Carv. Ed. Lond. Dub.—Aq. Car. Lond.—Ol. Car. Lond. Dub. Cop-jANDRUM sativum. Coriander. Pentand. Digyn. Umbellate. Semen. South of Europe. The seeds of this plant have a more pleasant odour when dried than when fresh; their taste is moderately warm. Like caraway, they are used as carminative, and likewise to cover the taste and flavour of some medi- cines, particularly of senna, when given under the form of infusion or tincture. Pimpinella anisum. Anise. Pentand. Digyn. Umbellate. Semen, Egypt. The seeds of anise have an aromatic odour, and a warm taste, with a share of sweetness. They afford, by distillation with water, a considerable quantity of an essential oil, having a strong, rather unpleasant odour, and a sweet taste, without much pungency. They are used chiefly as a carminative in dyspepsia, and in the flatulence to which infants are subject. A small quantity of the seeds may be taken, or, what is preferable, a powder composed of a few drops of the oil rubbed with sugar. Offic. Prep.—Ol. Pimpin. Anis. Ed. Lond. Dub.— Sp. Anis. L,ond.—Sp. Anis. C. Dub. The seeds of the following plants have qualities and virtues so very similar to those of the anise or caraway, that they do not require distinct consideration. They are used for similar purposes, but are scarcely entitled to a place in the Materia Medica. Anethum foeniculum. Fceniculum dulce. Sweet Fennel. Pen- tand. Digyn. Umbellate. Semen. Indigenous. Anethum graveolens. Dill. Pentand. Digyn. Umbellate. Semen. Spain and Portugal. Cuminum cyminum. Cumin. Pentand. Digyn. Umbellate. Semen. South ff Europe. TONICS. 211 Angelica archangelica. Angelica sativa. Garden Angelica. Pentand. Digyn. Umbellate. Semen; Folia; Radix. North of Europe. Of this plant, the root possesses the greatest share of the aromatic quality, though it also belongs to the seeds and leaves. Mentha piperita. Mentha Piperitis. Peppermint. Didynam. Gymnosp. Verticillate. Herba. Indigenous. Of the different mints, this is the one which has the greatest degree of pungency. The leaves have a consi- derable degree of aromatic odour and taste. They afford an essential oil, rich in the aromatic quality and pun- gency of the herb. Peppermint is used as a stimulant and carminative, to obviate nausea or griping, or to relieve the symptoms arising from flatulence, and very frequently to cover the taste and odour of other medi- cines. It is used for these purposes under the forms of the watery infusion, the distilled water, and the essen- tial oil. Offic. Prep—Aq. Menth. P. Sp. Menth. P. Ol. Menth. P. Ed. Mentha viridis. Mentha sativa. Spearmint. Didynam. Gym- nosperm. Verticillate. Herb. Indigenous. Mentha pulegium. Pennyroyal. Didynam. Gymnosp. Verticillate. Herba. Indigenous. These two mints, spearmint and pennyroyal, resem- ble the peppermint in their general qualities, and are used for the same purposes, but are rather less agreea- ble and pungent. Their essential oil and distilled water are also inserted in the Pharmacopoeia. Hyssopus officinalis. Hyssop. Didynam. Gymnosp. Verticillate. Herba. Asia, South and East of Europe. This plant, nearly allied to the preceding in botanical characters, is possessed of very similar qualities and vir- tues, and is sometimes employed for the purposes for which they are used. It has also been considered as a remedy in catarrh, though it can have no efficacy. 212 CHAPTER VI. OF ASTRINGENTS. It has been supposed that the fibres of the living body, either over the whole, or in part of the system, may become relaxed, or lose that density and contrac- tion which is necessary for the due performance of the several functions. And this is considered as an affection of the matter of which the fibre is composed, and not of the living or irritable principle connected with it. It has farther been imagined, that this relaxation may be removed by the application of those substances, which, when applied to dead animal matter, condense and con- stringe it; and such substances, classed as remedies, have received the appellation of Astringents. They are defined by Cullen: " Such substances as applied to the "human body produce contraction and condensation in " the soft solids, and thereby increase their density and " force of cohesion." And by the operation of this cor. rugating power, either directly exerted on a part, or extended by sympathetic action, the morbid affections arising from a state of relaxation are supposed to be re- moved. The arguments adduced in support of these medi- cines exerting such a power, appear more conclusive than those brought in proof of any of the other explana- tions of the operations of medicines, founded on the mechanical physiology. Astringents, it is observed, exert, in a remarkable manner, this corrugating power on dead matter; they are serviceable as medicines in those affections which seem to depend on a relaxed state of the solids; they even corrugate the fibres of living matter, as is evident from the sensation they impress on the tongue and fauces; and applied to bleeding wounds, they restrain the haemorrhage apparently by the same power. ASTRINGENTS. 213 We cannot, however, admit, without limitation, the suppositions on which this hypothesis is founded,—that the affections which astringents obviate depend on me- chanical laxity of the solids, and that these substances act solely by removing that laxity, by inducing a me- chanical ©r chemical change. Debility was indeed once ascribed to such a cause; but it is now admitted, that every degree of strength or weakness depends much more on correspondent variations in the state of the powers peculiar to living matter; and substances capa- ble of obviating diseases dependant on any state of de- bility, must be such as are capable of acting on these powers. Many substances accordingly, arranged as As- tringents, occasion very considerable alterations in some of the functions: they produce effects which cannot be referred to their condensing power, allowing them to possess it; and therefore, in all the changes they pro- duce, part of their operation at least must be referred to actions conformable to the laws of the living system. For reasons of this kind, some have denied the exist- ence of such a class of medicines as astringents. The substances which have usually received that appellation, they have considered as merely moderate stimulants, permanent in their action, and as differing little there- fore from tonics. It must be admitted, however, that there are sub- stances which immediately restrain excessive evacua- tions; and that although between these and tonics there is in several respects a close resemblance, in others they differ widely. The most powerful astringents, oak bark for example, or galls, are much inferior in their tonic power to other substances having little or no astringency; while there are powerful tonics which do not produce the immediate effects of astringents. There appears, therefore, to be a foundation for esta- blishing such a class as astringents, though it is very difficult to point out the precise nature of their opera- tion. It must be admitted, perhaps, that astringents possess a power of corrugating or condensing the animal 214 ASTRINGENTS. fibre. The very sensation they excite in the mouth ap- pears to be a sufficient proof of this, and it is farther established by chemical facts. That they likewise act as permanent stimulants, is proved by their power of removing intermittent fever and other states of the system connected with debility. The one power may be conceived perhaps to modify the other; and to this modification, or to their combined action, the effeots of astringents may be ascribed. The hypothesis of Darwin, that they act by producing absorption, accounts for some of their effects, but not for others, particularly their power of stopping haemorrhage. Astringents, from the powers they possess, are capa- ble of being applied extensively to the treatment of diseases. As stimulants, acting with considerable permanence, they may be substituted for tonics in diseases of debi- lity. It has been found accordingly, that they have power to stop the paroxysm of an intermittent fever, when given a short time before its accession: and in cases of debility, they seem to be often of utility, inde- pendent of their power of checking debilitating eva- cuations. It is however for restraining evacuations that astrin- gents are most usually employed. Haemorrhage, where it does not arise from a solution of continuity, depends on the contraction of the extreme arterial branches not being sufficient to resist the impulse of blood from the larger branches,—a deficiency of contraction generally owing to a debilitated state of these vessels. Astringents, as stimulants, slow and permanent in their action, and not sensibly increasing the force of the circulation, are calculated to obviate such a state; and this may be far- ther promoted by their corrugating power, extended by sympathetic action to the vascular fibre. Hence their use in menorrhagia, haemoptysis, and other discharges of blood; though they likewise frequently fail, from their operation being too slow and feeble, to resist the impetus of the circulation, or counteract the flow from a ruptur- ASTRINGENTS. 215 ed vessel. In epistaxis, or bleeding wounds, they are more powerful, as they can be more directly applied to the part. By a similar operation, they in some measure check serous effusions; hence their use to restrain colliquative sweats. In diarrhoea too, they appear to operate by checking the effusion of fluid from the exhalant vessels, and thus diminishing the increased stimulant operation, which from this cause is exerted on the intestines, and increases their peristaltic motion. In the latter stage of dysentery, where an increased evacuation appears to be connected with debility of the exhalant vessels, their cautious administration is advantageous. And in passive inflammation, attended with increased serous discharge, as in gleet, and in some forms of ophthalmia, the topi- cal application of astringents affords the most successful mode of treatment. In the administration of astringents, it is an obvious caution, that they ought not to be applied to check evacuations where these are critical, or where they are necessary to relieve a plethoric state of the vessels, or a state of increased action; at least unless the evacuation proceed to an alarming extent. Some narcotics, as opium, have sometimes effects apparently astringent. When increased discharges take place from irritation, these remedies, by diminishing irritability, lessen the discharge; they are thus service- able both in haemorrhage and in diarrhoea arising from that cause. But their mode of operation is obviously different from that of astringents, and in the cases in which they are useful, astringents would be less useful, and only by an indirect operation. Astringents may be subdivided into those belonging to the mineral, and those belonging to the vegetable kingdoms, which differ considerably from each other in flheir chemical properties, and probably therefore in the mode in which they produce their astringent effect. 216 ASTRINGENTS. FROM THE MINERAL KINGDOM. acidum sulphuricum. Ahgilla. Super-sulphas argill/set FOTASSJE. Calx. Ferrum. ZlNCUM. Cuprum. Plumbum. FROM THE VEGETABLE KINGDOM. quercus robur. quercus cerris. tormevtilla erecta. Polygonum bistorta. Anchusa tinctori v. h.aematoxylon campechianum. Rosa gallica. Arbutus uva ursi. Mimosa catechu. Kino. Pterocarpus draco. pistacia lentiscus. OF ASTRINGENTS FROM THE MINERAL KINGDOM. Acidum sulphuricum. Sulphuric Acid. Acidum Vitriolicum. Vitriolic Acid. Sulphur combines with oxygen in different propor- tions; when united with the largest proportion, it forms an acid extremely powerful from its state of concentra- tion, the Sulphuric Acid. This acid used to be obtained from the decomposition of sulphate of iron, the Green Vitriol of commerce, by heat, and hence the name of Vitriolic Acid which was given to it. It is now formed ASTRINGENTS. 217 by the combustion of sulphur. The sulphur, reduced to powder, is mixed with from one eighth to one tenth of its weight of nitrate of potash, by which its combustion, when begun, can be continued without the free access of atmospheric air, the nitric acid of the nitrate afford- ing the requisite quantity of oxygen. It is thus burnt in a large leaden chamber; the sulphuric acid, which is slowly formed, is absorbed by water placed in the bot- tom of the chamber, and the acid liquor is brought to the due degree of concentration, by exposing it to heat in glass retorts. It is of a thick consistence, and has an apparent tinctuosity; its specific gravity is 1.850; it is colourless and transparent; is highly corrosive, and pos- sesses all the general acid properties in an eminent de- gree. As obtained by this process, it is not perfectly pure, but contains a little sulphate of potash, and some- times a little sulphate of lead. The quantities of these, however, especially of the latter, are very inconsiderable; they are in a great measure separated when the acid is diluted, and hence this dilution not only renders it more convenient for administration, but likewise more pure. As a medicine, this acid is employed as a refrigerant, but principally as an astringent, and in this property it is undoubtedly superior to any other acid. It is used as an astringent to check the flow of blood in haemoptysis, and the colliquative sweat in hectic fever, indications which it fulfils better than any other article in the Materia Medica. It is sometimes also used in menorrhagia and diabetes; and as a tonic, founded on its astringent pro- perty, in dyspepsia. In its concentrated state, its dose can scarcely be measured. In the Pharmacopoeias, it is therefore ordered to be diluted. According to the for- mula given by the Dublin and Edinburgh Colleges, the Acidum Sulphuricum Dilutum consists of one part of the strong acid with seven of water; it is given in a dose from ten to thirty drops. The London College, without any sufficient reason for the deviation, have ordered, un- der the same name, an acid diluted with not much more than five parts of water. The Acidum Sulphuricum Vol. I. 2E 218 ASTRINGENTS. Aromaticum consists of the acid diluted with alkohol impregnated with aromatics, and is given in a similar dose. From its astringency, this acid is frequently added to gargles, which are employed to check salivation, or relieve relaxation of the uvula. Externally mixed with lard, in the proportion of half a drachm to an ounce, it has been used with advantage in psora, and it has also been given internally in the same disease. Offic. Prep.—Acid. Sulph. Dil. Ph. Ed. Lond. Dub. —Acid. Sulph. Aromat. Ed. Argilla. Argil. This earth, in its pure form, is insipid and inert; but in its saline combinations, at least all of them which, from their solubility, are sufficiently active, there exists a greater or less degree of astringent power. The Boles, of which the Armenian Bole (Bolus Armena) is the chief, are argillaceous earth, impregnated with oxide of iron; they were at one time employed as astringents, but are entirely inert, and are now expunged from practice. Super-sulphas argillje et potassa:. Alumen. Alum. This is a salt composed chiefly of argillaceous earth and sulphuric acid, the acid being in excess. It likewise always contains, however, a smaller portion of potash, and in some of the forms of it met with in commerce, sometimes also ammonia. It is found native, efflorescing generally in the interstices of what is named alum slate; or it is prepared by exposing alum ores, which are native compounds of argillaceous earth and sulphur, to atmospheric air; the sulphur absorbing oxygen, forms sulphuric acid, which unites with the argillaceous earth, with a portion of potash which the ore contains; or if this alkali is not present in sufficient quantity, either it or impure ammonia is added to the liquor obtained by lixiviation, so as to dispose it to crystallize. This liquor is then concentrated by boiling, so as to obtain, on cool- ing, the alum in a solid state, of a crystalline structure, though of no regular form. ASTRINGENTS. 219 This salt is in large transparent masses; it has a styp- tic taste, with a degree of sweetness. From the.excess of its acid it reddens the vegetable colours. It is soluble in eighteen parts of cold, and in less than two of boiling water. The variety termed Roche or Rock Alum (Alumen Rupeum) has a reddish colour from the pre- sence of a portion of oxide of iron. Common alum con- sists of 26 of acid, 12.5 of argil, 10 of potash, and 51.5 of water. Alum, from its astringent power, is employed to check haemorrhagies and serous evacuations: it is thus given in menorrhagia, leucorrhoea, and diabetes; and in leucorrhoea, is perhaps more successful than any other astringent. It has likewise been used, though less fre- quently, in intermittent fever, and in colica pictonum. Its dose is from five to ten grains. The addition of an aromatic is generally necessary, to prevent it from ex- citing nausea, when it is given in the solid form; but the best •form of administering it, is that of Alum Whey (Serum Aluminosum), prepared by adding two drachms of pounded alum to a pint of hot milk; the dose of this is three or four ounces. Externally alum is frequently used as the basis of astringent gargles, and of injections used in gleet; and dissolved with sulphate of zinc or copper, it forms very styptic solutions, employed to check haemorrhage by direct application. Offic. Prep— -Sulph. Alum. Exs. Pulv. Sulph. Alum. C. Ed.—Liq. Alum. C. Lond. Calx. Lime. Calx Viva. Quicklime. Lime is a primary earth, found abundantly in nature, in several states of combination. It is obtained by ex- posing any of the native compounds of it with carbonic acid, usually chalk, limestone, or marble, to a heat gra- dually raised, so that the acid is expelled, and the lime remains pure. It is soluble in water, in sparing quan- tity; about seven hundred parts being required for its solution. Yet even in this weak state of impregnation, the solution which is known by the name of Lime Water (Aqua Calcis) has a strong styptic taste, and is 220 ASTRINGENTS. capable of exerting important chemical agencies, as well as of acting on the living system. As an astringent lime water is employed in diabetes, and in diarrhoea: the dose is one or two pounds in the course of the day. It is used likewise in dyspepsia, in which it proves useful, more by its tonic and astringent power, than by its effect in neutralizing acid in the stomach. Externally it is applied as a wash in ill-conditioned ulcers. Offic. Prep.—Aq. Calc. Ol. Lini cum Calce. Ed. Carbonas calcis. Carbonate of Lime. The various kinds of carbonate of lime, Chalk (Creta Alba), Crabs Claws (Chelae Cancrorum), Oyster Shells (Testae Ostreorum), are not unfrequently used in diar- rhoea, but they evidently prove useful, not by any real astringent power, but by correcting the acidity which so frequently occasions or aggravates that disease. They rather belong, therefore, to the class of antacids. Ferrum. Iron. (Page 174.) This metal has been already considered as a tonic; it is likewise employed as an astringent to check increased evacuations. It is thus used with advantage in some forms of passive haemorrhage, particularly menorrhagia. The advantages derived from it in such cases, may be supposed to depend on its tonic power; the styptic taste, however, of its saline preparations, is a sufficient proof of the presence of astringency to a certain extent; and it is not improbable that this may coincide with, or modify the operation connected with its action as a tonic. The sulphate of iron is the preparation in which this astringent property is most obvious. Zincum. Zinc (Page 177.) This metal has likewise been considered as a tonic. Its saline preparations have, however, a considerable degree of astringency, and there are several medicinal applications of them founded on this quality. Sulphate of Zinc (Sulphas Zinci) has been employed ASTRINGENTS. 221 internally as an astringent in chronic dysentery, and in the treatment of intermittent fever: but from its emetic power its operation is liable to be harsh, and is not easily regulated. Its solution is in common use as an in- jection in gonorrhoea, when the inflammatory state has subsided, and in gleet; two grains being dissolved in an ounce of water, and it frequently succeeds in checking the discharge, apparently from its astringent power. A solution of nearly the same strength is likewise used as a colly rium in ophthalmia; the astringent power of this being increased, according to a formula in the Edin- burgh Pharmacopoeia, by the addition of a few drops of diluted sulphuric acid. Dissolved with alum, it forms a very styptic liquor, which has long been in use for stopping haemorrhage, and checking increased dis- charges by external application. Offic. Prep.—Sol Sulph. Zinc. Ph. Ed.—Liq. Alum. Comp. Ph. Lond. Acetate of Zinc, under the form of solution (Solutio Acetitis Zinci), is obtained by adding a solution of ace- tate of lead to a solution of sulphate of zinc, a decom- position immediately taking place, and sulphate of lead being precipitated, while acetate of zinc remains dis- solved. This has long been in use as a mild astringent injection in gonorrhoea, less liable to produce irritation, or to check the discharge suddenly than the solution of sulphate of zinc, and rather more active than the solu- tion of acetate of lead. It has therefore received a place in the Edinburgh Pharmacopoeia. A solution of the salt in alkohol has been introduced into the Dublin Pharma- copoeia, and when used is largely diluted with water. Cuprum. Copper. (Page 179.) This metal has so far an analogy to the preceding ones, that, along with the general action which it exerts on the system, capable of obviating spasmodic affec- tions, it has a degree of astringent power. This too is conspicuous, principally in its combination with sulphu- ric acid, the sulphate of copper. This in solution is some- 222 ASTRINGENTS. times used externally as an astringent; and dissolved with alum in water, to which a portion of sulphuric acid is added, it forms a very styptic solution, formerly nam- ed Aqua Styptica, sometimes employed by direct ap- plication to restrain haemorrhage. The formula has a place in the Edinburgh Pharmacopoeia. • Offic. Prep.—Sol Sulph. Cupr. Comp. Ph. Ed. Plumbum. Lead. This metal, when rendered capable of acting on the system by oxidation, or combination with acids, pro- duces very deleterious effects, and proves a powerful, though insidious poison. Nor is it easy to explain its mode of action. It appears to act peculiarly on the mus- cular fibre, repressing action, and at length exhausting the irritability of the muscles. When introduced slowly into the system, the intestines are first affected, consti- pation from diminished action takes place, accompani- ed frequently with severe pain. Tremor and debility of the voluntary muscles succeed, and are followed by com- plete paralysis, the muscles losing their firmness and cohesion. When a large quantity of any of the ac- tive preparations of lead is received into the stomach, these symptoms occur suddenly and with violence, giv- ing rise to what is named Colica Pictonum, and the same disease is sometimes suddenly induced by the progressive accumulation of the metal in smaller quan- tities. A sense of contriction is felt in the stomach and bowels, with obstinate constipation and the most severe pain; the pulse is small and hard; respiration becomes laborious; there is general muscular debility and tre- mor, accompanied with cold sweats and convulsions, which have often a fatal termination. From this power of repressing muscular action, lead produces effects analogous in some respects to those of astringents, and it is regarded as an astringent, though its mode of operation is probably dissimilar. The pre- parations of it which have been applied to medicinal use, ASTRINGENTS. 223 are the semi-vitrified oxide, white oxide or sub-car- bonate, and the acetate and super-acetate. Lithargyrum. Litharge. The substance thus nam- ed is the semi-vitrified oxide (Oxidum Plumbi Semi- Vitreum). It is usually obtained in the calcination of lead, with the view of separating the silver, which is frequent- ly associated with it; the flame, with a current of air, being made to reverberate on the surface of the melted metal. It is in flakes of a yellow colour, with some- what of a vitreous lustre. A small quantity of carbonic acid, not exceeding 4 parts in 100, exists in it, appa- rently, however, not essential to its constitution. It is used only in some pharmaceutical preparations, parti- cularly for forming, when boiled with oil, a plaster which serves as the basis of other compound plasters, and which is itself sometimes applied as a healing dres- sing to wounds, proving useful by excluding the air. Offic. Prep.—Emp. Oxid. Plumb. Ph. 'Ed. Lond. Dub. Minium. Red Lead.—This is an oxide containing about 12 of oxygen in 100 parts. It is sometimes ap- plied to the same purposes as litharge, and an ointment formerly in use as a cooling application was prepared by rubbing it with vinegar and oil. It might be discar- ded, however, from the Pharmacopoeia. Cerussa. Cerusse, or White Lead.—This is pre- pared by exposing plates of lead to the vapour arising from vinegar; a white crust is formed on their surfaces, which, when it has accumulated sufficiently, is scraped off, and reduced to a fine powder by levigation. The nature of this substance has not been very well ascer- tained. It has been regarded merely as an oxide; hence the name Oxidum Plumbi Album, given to it by the Edinburgh College. A little carbonic acid, being gene- rally contained in it, either absorbed from the atmos- phere, or formed from the partial decomposition of the acetic acid, it has been considered as a sub-carbonate; and the London College have defined it as such, while. 224 ASTRINGENTS. for a reason not easily imagined, they have named it Car- bonas Plumbi. From theory, it might be inferred to con- tain a portion of the acetic acid by which it is formed; the Dublin College have accordingly named it Sub- Acetas Plumbi, and it is not improbable that this is most correct. It is used only externally, being applied in fine powder to slight cases of excoriation or inflam- mation, and used particularly to relieve these affections in children,—a practice, however, which, from some observations, appears not to be altogether without dan- ger, and which is unnecesssry, as the levigated calamine stone answers equally well. It is used likewise as the basis of an ointment, which is sometimes applied as a cooling dressing to inflamed parts. Offic. Prep.—Ungt. Oxid. Plumb. Alb. Ph. Ed. Acetas Plumbi. Acetate of Lead.—There are two compounds of lead with acetic acid, medicinally em- ployed. One is the salt which has been long known by the name of Sugar of Lead, (Saccharum Saturni); the other a solution, which was named Goulard's Extract of Lead; and it is only lately that the relation between these has been established. The first had been regarded as the proper acetate of lead. Thenard found, that it is the super-acetate, or con- tains an excess of acid, which is necessary to give it its usual crystalline form, which is that of a slender four or six sided prism. When its solution is boiled with a lit- tle oxide of lead, the neutral acetate is formed, which crystallizes in plates. Goulard's Extract, which is pre- pared by boiling vinegar on litharge, Dr. Bostock found to be a solution of the natural acetate. And the terms of Acetate and Super-acetate are now employed by the London College to distinguish these preparations. Super-Acetas Plumbi. Super-Acetate of Lead. This is still named Acetate of Lead (Acetas Plumbi) in the Edinburgh Pharmacopoeia, the nature of it hav- ing only lately been ascertained. It is the sugar of lead of the old nomenclature. The process for preparing it ASTRINGENTS, 225 consists in boiling vinegar on cerusse, until the acid ac- quire a sweet taste, and evaporating the liquid, so that on cooling it affords crystals: it is usually prepared on a large scale. It is in masses composed of slender prisma- tic crystals, aggregated, of a yellowish colour, slightly efflorescent: it has a very sweet and styptic taste, is abundantly soluble in water, but scarcely forms a trans- parent solution even with distilled water, owing to a slight decomposition, in consequence of which a little sub-acetate is precipitated. It consists, according to Thenard's analysis, of 58 of oxide, 26 of acid, and 16 of water. The medicinal use of this salt is nearly limited to its external application. Yet some practitioners have re- commended it in different cases of profuse evacuation, particularly in haemorrhage, where other remedies have failed: it has thus been given in menorrhagia, in the dose of half a grain repeated every four hours: it has likewise been employed in obstinate leucorrhoea, and to restrain the colliquative sweat accompanying hectic fe- ver. From the deleterious agency, however, of lead on the system, it is a remedy which must be used with re- luctance, and which is accordingly scarcely ever ven- tured on in modern practice. There is one circumstance too, that renders its administration more difficult,—its being liable to be considerably influenced by idiosyncra- sy; many facts having sufficiently'established, that its action is extremely unequal, quantities of it having been often taken without any injurious effect, which, in other cases, would have proved in the highest degree delete- rious. As an external application, it is often employed to obtain its astringent effect. A solution of it, of the strength of three grains to an ounce of water, is used as an injection in gonorrhoea; and producing no irritation, is not liable to be attended with the injurious conse- quences which sometimes arise from preparations more active. A solution rather weaker is emploved as a collv- Vol. I. 2F - * 226 ASTRINGENTS. rium in ophthalmia, and can be applied with safety, even in the state of active inflammation. A solution somewhat stronger is a common application in superficial inflam- mation; and an ointment, of which it is the basis, is of- ten employed as a dressing to inflamed or excoriated parts. Its saturated solution, combined with vinegar, is also frequently employed as a discutient. Facts have been brought forward, which apparently prove, that the general effects of lead on the system have been produc- ed by the incautious or too long continued use of these external applications; while, in many cases, they have unquestionably been extensively employed without the production of any bad effect, and indeed are so in com- mon practice; the opposite facts, therefore, if the obser. vations with regard to them have been correct, are pro- bably to be accounted for from the peculiar idiosyncra- cy, which, as has been remarked, exists with regard to the action of lead on the system, in consequence of which some individuals are more liable to be affected by it than others. The neutral acetate of lead, it has been stated above, forms the basis of what has been named Goulard's Ex- tract,—a preparation which has long been in use among surgeons. It is the Aqua Lithargyri Acetati of the former edition of the London College, now named Liquor Plumbi Acctatis; and prepared by boiling vinegar on litharge. Although it differs in chemical composition from the preceding preparation, it does not appear to differ from it in medicinal powers. It is used diluted with water, as a lotion in cutaneous diseases, or as an application to inflamed surfaces. In the original formula for the preparation of this lotion given by Goulard, a little ardent spirit was added to it, and this being in common use has been received as an officinal prepara- tion by the London and Dublin Colleges. Offic. Prep.—-Ungt. Acet. Plumb. Ph. Ed. Lond. Dub.—Liq. Plumb. Acet. Dilut. Ph. Lond. Dub.— Cerat. Plumb. Composit. Ph. Lond. ASTRINGENTS. 227 OF VEGETABLE ASTRINGENTS. The property of astringency in vegetables, denoted by its effect of corrugating the animal fibre, appears to be dependent on a common chemical principle, or at least to be connected with some peculiarity of composi- tion; since vegetable astringents uniformly possess cer- tain common chemical properties. Thus their astrin- gency is extracted both by water and by alkohol; these infusions strike a purple or black colour with any of the salts of iron, deeper in general as the astringent is more powerful; and they are capable of corrugating, more or less strongly, dead animal matter, as is shown in their operation in the process of tanning. In the farther investigation of this subject, it was found, that a peculiar acid exists in the more powerful astringents; the acid which, from being contained abun- dantly in galls, has been named Gallic, and the general chemical characters of which, in the preliminary sketch on the principles of Pharmaceutic Chemistry, have been enumerated. This acid having the property of striking a deep purple colour with the salts of iron, the chemical change which had been more particularly considered as the test of astringency, was supposed to be the astrin- gent principle. To this, however, there existed a very obvious ob- jection, that the acid, when obtained insulated, was pos- sessed of no great astringency, and scarcely indeed of that property in any sensible degree; and farther, that the colour it did strike with the salts of iron was less deep than that from the infusions of the more powerful astringents. The researches of Seguin, some years ago, threw more light on this subject by the discovery of a different principle existing in astringents, and having a better claim to be ranked as the principle of astringency. Ap- plying the proper test to discover it, that of the animal 228 ASTRINGENTS. matter, on which it peculiarly operates, he found, that on adding a solution of animal gelatin to the infusion of a vegetable astringent, as that of galls or oak bark, a co- pious precipitation takes place, consisting of this princi- pie in combination with the gelatin. Being the agent which gives to astringents their property of tanning, it has received the name of Tannin, and its properties, as a proximate principle of vegetables, have been already stated. That it is the principle of astringency in vegetables, admits now of little doubt. Gallic acid has no such power, while tannin has a harsh styptic taste, and the power of corrugating the animal fibre. Seguin had sup- posed, that in the operation of tanning, its action is faci- litated by that of the gallic acid, the acid partially de- oxidizing the skin, and thus bringing it nearer to the state of gelatin with which the tannin combined. A simi- lar action might be supposed to be exerted on the ani- mal fibre in the production of the astringent effect. The theory of Seguin, however, was established by no proof, and the fact alone that some of the most powerful astrin- gents, as catechu or kino, contain no gallic acid, but tannin mixed only with mucilage or extract, is a proof that it is to the action of this principle that the whole effect is to be ascribed. If astringency, as exerted by vegetables, is thus to be considered as the result of the chemical action of the principle on which it depends, there is considerable diffi- culty, as has been already remarked, in conceiving how it can be exerted in the animal system, especially in a distant part, when the astringent acts only on the sto- mach. It can only be conceived, that corrugation, or some similar change, is produced by it in the fibres of the stomach, which may be propagated by sympathy to distant parts, nearly in the same v/ay as the impression of cold is communicated. ASTRINGENTS. 229 Quercus robur. Oak. Monoec. Polyand. Amentacee. Cortex. In- digenous. The bark of this tree possesses a large share of as- tringency, which it yields to water. The infusion con- tains both gallic acid and the tanning principle, the latter in a considerably quantity, attached to the ligneous fibre, which forms the basis of the bark; an ounce of bark afforded, in Mr. Davy's experiments on the principal astringents, 111 grains of solid matter by lixiviation, of which 77 were tannin. Oak bark has been used as a remedy in haemorrhage, diarrhoea, and intermittent fever, given in a dose from 15 to 30 grains. In modern practice, its strong infusion or decoction is occasionally employed as an astringent gargle in cynanche, as an injection in leucorrhoea and profuse menorrhagia, and as a fomentation in haemor- rhoids and prolapsus ani. Offic. Prep.—Extr. Cort. Querc. Dub. Quercuo cerris. Monoec. Polyand. Amentacee. Cyniphis nidus. Galla. Galls. South of Europe. The tubercles, named Galls, are found on the" branches of this tree. Their production is occasioned by the bark being pierced by an insect of the cynips genus, to deposite its egg. The juice exuding slowly, is inspissated, and hardens. The best galls are heavy, knotted on the surface, and of a blue colour. They are nearly entirely soluble in water, at least with the assistance of heat; the infusion reddens the vegetable colours from the action of the gallic acid, and this acid can be pro- cured in considerable quantity, by allowing the infusion to remain exposed to the air until its other principles are decomposed, or by sublimation from the galls. The infusion too contains a large quantity of tannin, as it gives a very copious precipitate with solution of gelatin. It has farther been supposed to hold dissolved extract and mucilage; but the existence of extract is doubtful, and from Dr. Bostock's experiments there appears to 230 ASTRINGENTS. be no sensible portion of mucilage. The proportion of tannin varies considerably in different specimens of galls. In Mr. Davy's analysis of Aleppo galls, 500 grains af- forded to water by lixiviation 185 grains of solid mat- ter, of which 130 were tannin, 31 gallic acid, 12 saline and earthy matter, and 12 supposed to be mucilaginous and extractive matter. In medical practice, galls, though so powerfully as- tringent, are not much employed, and are seldom inter- nally administered. The strong infusion or decoction has been applied to the same purposes as the decoction of oak bark. And an ointment composed of the galls in fine powder with eight parts of simple ointment is used as ar astringent application to haernorrhoidal affections. Offic. Prep.—Tinct. Gallar. Ph. Dub. Tormentilla erecta. Tormentil. Icosand. Polygyn. Senticosa. Radix. Indigenous. The root of tormentil is strongly astringent, with little flavour or bitterness, and though not chemically examined probably owes its astringency to tannin. It has been used in diarrhoea, under the form of decoction, and in intermittent fever, in substance, in the dose of from half a drachm to a drachm. But it is now nearly dis- carded from practice. Polygonum bistorta. Bistort. Octand. Trigyn. Oleracee. Radix. Indigenous. The root of this plant is a pure and very strong as- tringent; as such it has been used in diarrhoea and in intermittent fever, in a dose from a scruple to a drachm. But having probably no superiority over other astrin- gents, and no peculiar virtue, it has fallen into disuse. Anchusa tinctoria. Alkanet. Pentand. Monogyn. Asperifolie. Radix. South of Europe. The cortical part of the root of this plant has a deep red colour, which has the singular property of not being extracted either by water or alkohol, but readily by ex- ASTRINGENTS. 231 pressed oils. It possesses a slight degree of astringency; but it is now only employed to communicate colour to ointments. ILematoxylon campechianum. Lignum Campechense. Log- wood. Decand. Monog. Lomentacee. Lignum. South America. The wood of this tree is of a very deep red colour; it has scarcely any smell; its taste is sweetish and as- tringent. Its active matter is extracted by water, and by alkohol, leaving the ligneous fibre which is its base un- dissolved; both solutions strike a deep purple colour with the salts of iron, and give a precipitate with gela- tin. Logwood has been employed in medicine as an astringent, in diarrhoea and chronic dysentery, under the form of the decoction, or the watery extract. The extract has been proposed to be used as a substitute for kino. Offic. Prep.—Extr. Haematoxyl. Camph. Ph. Ed. Dub. Lond. Rosa Gallica. Rosa Rubra; Red Rose. Icosand. Polyg. Senticose. Petala. South of Europe. The petals of this species of rose have a slight degree of astringency, which is most considerable before they are expanded, and it is in this state that they are collect- ed and dried for use. The fresh leaves of the flowers are made into a conserve with sugar, which was at one time regarded as a remedy of some power in haemopty- sis and phthisis, but which has long been ackowledged to be perfectly inert. The infusion of the dried leaves, slightly acidulated by the addition of sulphuric acid, forms a pleasant astringent gargle. Offic. Prep.—Inf. Ros. Gall. Cons. Rus. R. Syr. Rosae Ph. Ed.—Mel Rosae. Lond. Dub. Arbutus uva ursi. Bears Whortie-Berry. Decand. Monog. Bicornes. Folia. Europe, America. The leaves of this plant have a bitter astringent taste, without any odour. Their watery infusion strikes a deep black colour with the salts of iron, and from their 232 ASTRINGENTS. known astringency, which adapts them even to the pur- pose of tanning, probably contains a large proportion of tannin. From its astringency, uva ursi has been employed in menorrhagia and other fluxes. It has however been used more particularly in cystirrhcea, calculus, and ul- cerations of the urinary organs. In checking the in- creased secretion of mucus from the bladder, which constitutes the first of these diseases, it appears to be superior to other astringents; to calculus, in common with other bitters and astringents, it affords relief, pro- bable by its action on the stomach preventing the gene- ration of acid. More lately it has been recommended in phthisis. Its dose is half a drachm of the leaves in pow- der, twice or thrice a-day. Mimosa catechu. Polygam. Monoec. Lomentacee. India. Ligni Extractum. Catechu. Terra Japonica. To this substance, formerly known by the absurd name of Japan earth, the appellation of Catechu is now appro- priated. It is an extract prepared by boiling the interior wood of the tree with water, and the tenacious residual mass is dried by exposure to the air and sun. It is of a yellow or brown colour, has a bitter and astringent taste, leaving an impression of sweetishness; but its qualities vary considerably. Two kinds are at present met with in the shopb; one is of a light yellowish brown colour, is smooth and uniform in texture, breaks short, is soft and light; the other is of a dark brown colour, more heterogeneous, heavier, and considerably harder. Catechu is almost entirely soluble in water with the assistance of heat, the residuum consisting of accidental impurities. It is nearly equally soluble in alkohol. Its solution strikes a deep black colour with the salts of iron, and gives an abundant precipitate with animal gelatin. From Mr- Davy's experiments, it appears to be composed of tannin, extractive matter and mucilage; the proportions in the best catechu being 54.5 of the first, 34 of the second, 6.5 of third, and 5 residual mat- ter. Our knowledge with regard to the principle named ASTRINGENTS. 233 Extract is so imperfect, that it is difficult to establish any certain conclusion with regard to it; and the sub- sequent experiments of Dr. Bostock, as to the modes of separating what is called Extract from the Tannin of catechu, do not exactly accord with those of Mr. Davy. Dr. Bostock has remarked, too, that catechu gives indi- cations of the presence of gallic acid, and that its watery infusion even reddens the more delicate vegetable colours. Catechu is in common use as an astringent, and in the uniformity and certainty of its operation is probably equal, or even superior to any of the vegetable astrin- gents. It is used in diarrhoea generally under the form of the infusion, or the tincture: or the officinal preparation, the electuary of catechu, consisting of catechu and kino with some aromatics and a little opium is diffused in water, forming what has been named the Japonic Mix- ture. In substance it may be given in a dose from 10 to 20 grains, which may be frequently repeated. Under the form of troches, it is sometimes used in relaxation of the uvula, or sponginess of the gums, being allowed to dissolve slowly in the mouth. Offic. Prep.—Elect. Catechu. Inf. Catech. Tinctt Catech.—Ph. Ed. Lond. Dub. Kino. The substance distinguished by this name was in- troduced a number of years ago into the Materia Medica as a powerful astringent, little being known with regard to its origin, farther than it was said to be the produce of Africa, and obtained probably from the plant afford- ing it by exudation. Subsequent to its introduction, it was met with in the shops very various in its qualities: it still is so, and is obviously of different origin, though there is considerable obscurity with regard to the natural history of these varieties. The London College have described it merely as the produce of an African plant unknown. The Edinburgh College have inserted it in their catalogue of simples, as the concrete juice of the Vol. I. 2 G 234 ASTRINGENTS. Eucalyptus Rcsinifem,—a tree a native of New Hol- land; and there is reason to believe that at least part of what is called Kino in the shops is imported from that country, and is the produce of this vegetable. The Dub- lin College have considered kino as the product of the Butea Frondosa, on the authority of Roxburgh; but in- correctly, as Dr. Duncan has remarked. He has farther observed, what is perfectly just, that much of the kino of the shops bears all the appearance of an extract arti- ficially prepared, and is known to be formed from diffe- rent astringent vegetables. It is not very easy to discriminate exactly among these various substances, and to assign to each its real origin. One variety, and which bears the highest price in the shops, has all the appearance of a natural produc- tion: slender twigs are intermixed in its substance; it is of a reddish brown colour, with a resinous lustre, is very brittle, and has a bitterish astringent taste. This corres- ponds in its characters with the substance first intro- duced as kino, and is still said to be the produce of Africa, and to be imported from Senegal. The kind from New Holland has also the appearance of a natural production, fragments of bark being intermixed with it; it is in more solid masses than the other, is less brittle, and with its astringency has a disagreeable mawkish sweetish taste. The third kind, and which is most com- monly met wiih, has the appearance of an extract tho- roughly dried; it is in small fragments, with a resinous fracture, is of a bi own colour, more approaching to black than the others, and has a taste astringent and slightly bitter. This Dr. Duncan has stated is said to be the produce of the Coccoloba Uvifera. I have also been in- formed, that it is the Extract of the wood of the ma- hogany. The analysis of kino has been executed; but from the difficulty of ascertaining exactly to what substance the name is applied, there is a difficulty in appropriating the results to any of the varieties that are met with. All of them, however, appear to contain a large proportion of ASTRINGENTS. 235 tannin; their solutions giving a deep colour, not purple however, but green, with salts of iron, and a copious precipitate with gelatin. The active matter of all or the greater number of them is soluble in water with the assistance of heat, and is still more easily soluble in alkohol. Kino has been employed as an astringent for the same purposes as catechu, and they are often given in combi- nation. The catechu being more uniform in its qualities, ought perhaps to be preferred. Offic. Prep.—Tinct. Kino, Ph. Ed. Lond. Dub.— Pulv. Kino. Comp. Lond. Pterocarpus Draco. Sanguis Draconis. Dragon's Blood. Dia- delph. Decand. Papilionatee. Resina. South America. The substance to which the absurd name of Dragon's Blood has been given, is a resinous concrete of a dark red colour, and heterogeneous texture, varying also fre- quently in its qualities as it is met with in the shops. It is insipid; and though it has been considered as an as- tringent, has probably no such power, nor is it now applied to any medical use. Pistacia Lentiscus. Mastiche. Mastich. Dioecia. Pentand. Amentacee. Resina. South of Europe. The resin named Mastiche is the produce of this shrub by exudation. It is in small rounded fragments of a light yellowish colour, nearly transparent, brittle, and hard, but when pressed or chewed becoming some- what tenacious. It is chiefly resinous, and is hence dissolved by alkohol, a substance however remaining undissolved, tenacious and elastic, approaching in it its characters to caoutchouc. Mastiche is insipid, and nearly inodorous, giving only a slightly fragrant smell when heated. Though it has been regarded as an astringent, and as such was at one time employed in medical prac- tice, it has no sensible activity, and might be discarded from the lists of the Materia Medica. It is used from its insolubility and tenacity to fill the cavity in carious teeth. 236 SECOND DIVISION. OF LOCAL STIMULANTS. UNDER this division are comprehended those reme- dies, the stimulant operation of which is directed to particular organs. This comprises Emetics, Cathartics, Diuretics, Sialogogues, and those various other classes that have usually been arranged under the title of Eva- cuants, their local operation giving rise to increased secretion, or increased evacuation. CHAPTER VII. OF EMETICS. Emetics are defined, Medicines which excite vo- miting, independent of any effect arising from the mere quantity of matter introduced into the stomach. This definition, however, requires to be still more limited; for there are many substances which occasionally induce vomiting, that are not usually ranked as emetics. All bitter and nauseous drugs have this effect, when given in large doses, or in an irritable state of the stomach; and it occurs frequently as the consequence of the ac- tion of many stimulants and narcotics. The emetic operation, however, from these causes, is neither uni- form nor certain: there are, on the contrary, a number of substances, many of which have no very nauseous taste, or which can have that taste concealed, but which still excite vomiting when given in a sufficient dose in EMETICS. 237 every individual, and in every state of the stomach. To these substances the appellation of Emetics is exclu- sively applied. They may therefore be defined, Sub- stances which excite vomiting, independent of any effect arising from the quantity of matter introduced into the stomach, of any nauseous taste or flavour, or of any narcotic or acrid power. When an emetic has been given in a proper dose, the stomach remains for some time undisturbed. But in 10, 15, or 20 minutes an uneasy sensation, with nausea, supervenes, which continues increasing until vomiting begin. While the nausea only is present, the countenance is pale, the pulse is feeble, quick and irregular, and there is a feeling of cold; but during the action of vo- miting the face becomes flushed, the pulse is quickened, though still feeble, and remains so in the interval of vomiting. The vomiting generally recurs twice or thrice, and then ceases; a degree of nausea remains, which goes off only gradually; there is a degree of lan- guor, and often a disposition to sleep; the pulse is weak and slow, but becomes gradually fuller; the skin is usually moist. The general theory of the operation of vomiting is sufficiently evident. The vermicular or peristaltic mo- tion of the stomach, by which the food is propelled through the pylorus, is inverted; the diaphragm and abdominal muscles are calkd into action by association; the pylorus js contracted, and the contents of the sto- mach are forcibly discharged upwards. In many cases of vomiting, especially when violent, the peristaltic mo- tion even of the upper part of the intestinal canal is also inverted, and bile is brought into the stomach from the duodenum. At the same time, it is very difficult to explain how the peristaltic motion is inverted by emetics. It is a sin- gular fact, that any substance acting as an unusual sti- mulus to the stomach seldom increases its motion, so as to occasion a more speedy discharge of its contents by the pylorus. The motion, instead of being increased, is 238 EMETICS. more commonly inverted, and hence vomiting is the effect peculiarly resulting from such local stimul antac. tion. Nor is it easy to assign any cause for this specific operation. Dr. Darwin gave a different explanation of the nature of vomiting. He considered it as the effect, not of in- creased, but of decreased action of the fibres of the sto- mach. When an emetic is administered, it produces, he observes, the pain of sickness, as a disagreeable taste in the mouth produces the pain of nausea: these uneasy sensations not being acutely painful, do not excite the organ into greater action, but rather repress the motions already existing. The peristaltic motion of the fibres of the stomach becomes languid from the want of the usual stimulus of pleasurable sensation, and in consequence stops for a time, and then becomes inverted, which gives rise to the phenomena. In this theory, there is however equally a deficiency in explaining how the in- version of the motion is effected. There is a considerable difference among individuals with regard to the facility with which vomiting is excit- ed. This susceptibility is also liable to be altered by dis- ease. In the greater number of febrile affections, vomit- ing is easily excited; while in several of the diseases of the class Neuroses, as mania, melancholia and hypo- chondriasis, it is excited with much more difficulty. In the case of poisons, which induce inflammation of the stomach, vomiting is almost a constant symptom; while in those which act by a narcotic power, and in which the irritability of the stomach is impaired, a very power- ful emetic is required to produce any effect. Although nausea or sickness generally accompanies vomiting, this connection is not a necessary one. Some emetics, as sulphate of zinc, act without occasioning much nausea; while others, as tobacco, excite it in a greater degree than is proportioned to their emetic pow- er,—a circumstance sometimes requiring to be attended to in the administration of individuals of this class. EMETICS. 239 The feeble and low state of the pulse, which attends vomiting, has been ascribed either to direct association between the motions of the stomach and those of the heart; or to the nausea excited, which, like other dis- agreeable sensations not acutely painful, have a de- pressing effect, being equivalent probably to an abstrac- tion of stimulus. Emetics, at least those which are mild in their opera- tion, do not appear to waste the irritability of the sto- mach: they have rather an opposite effect: hence diges- tion is often vigorous after vomiting, and hence too gen- tle emetics are often serviceable in dyspesia, and in the temporary diminished tone of the stomach occasioned by intoxication. The state of the stomach produced by vomiting seems to be often extended to the vessels of the skin; it is therefore followed frequently by diaphoresis, and is one of the most powerful means of removing spasmodic stricture from the surface of the body. Emetics have a remarkable power of increasing ab- sorption: hence the benefit they afford in anasarca, and the sudden disappearance of tumors which some- times happens after violent vomiting. Emetics frequently occasion increased evacuation from the intestinal canal; and if they fail to excite vo- miting, very generally operate as cathartics. Some are more apt to have this effect than others, as the prepara- tions of antimony compared with ipecacuan. From the different indications which emetics are ca- pable of fulfilling, they are adapted to the treatment of many morbid affections. Where disease depends on a disordered state of the stomach, arising from over-distention, the presence of acrid or indigestible matters, or any other cause, vo- miting is the easiest and most effectual mode of afford- ing at least present relief. Hence its utility in all cases of indigestion, impaired appetite, acidity in the stomach, pyrosis, or anorexia; in the symptoms arising from in- toxication, and where poisons of any kind have been swallowed. 240 EMETICS. From the strong action of the diaphragm and abdo-s minal muscles in vomiting, the gall bladder and hepatic ducts are emptied of their contents; and hence jaundice, owing to obstruction from biliary calculi, is sometimes suddenly relieved by vomiting. A similar pressure is supposed to be exerted during vomiting on the thoracic viscera, and from this has been explained the expecto- rant effects of emetics, and the relief they afford in some varieties of asthma and catarrh. In the different varieties of febrile diseases, much ad- vantage is derived from the administration of an emetic, especially in the commencement of the disease. In sy- nocha, where there are symptoms of highly increased action, and particularly where there is determination of blood to the head, lull vomiting may be attended with some danger; and in typhus fully established, it cannot be expected to be of much benefit. In the slighter cases of pyrexia, it is often attended with marked advan- tage. The emetic should be given in the evening, as its operation leaves a tendency to sleep, and to diaphore- sis, which it is useful to promote. At one time, the practice of giving emetics in fever in such doses as to excite nausea without producing vomiting was common. It is more distressing to the patient, and does not appear to be equally effectual in stopping the progress of the disease. This mode, how- ever, of giving nauseating doses of emetics, is often useful in haemorrhage, where full vomiting would be dangerous; the nausea excited diminishes the force of the circulation, and hence it is sometimes employed in haemoptysis and menorrhagia. From the powerful effects of emetics, their improper administration may be extremely hurtful, and there are various states of the system which either prohibit their use, or allow them to be employed only with caution. During the operation of vomiting, the blood returns with more difficulty from the head, owing partly to the pressure on the descending aorta, and partly to the in- terrupted respiration, by which the transmission of blood EMETICS. 241 through the lungs is impeded; hence the redness of the countenance, and the vertigo which sometimes accom- pany it. From this cause it must be attended with dan- ger in all cases where there are symptoms of determina- tion to the head, and more especially in plethoric habits. From the strong action of the abdominal muscles ex- erted in vomiting, it has been considered as not without risk in visceral inflammation, in the advanced stage of pregnancy, and in hernia and prolapsus uteri. In ex- treme debility, there is danger of the patient sinking under the violence of the operation. The frequent repe- tition of emetics n chronic diseases is in general preju- dicial, by weakening the tone of the stomach, and ren- dering its motions more liable to be inverted by slight causes. The mode of administering emetics does not admit of many general observations. They should be given in the form of draught; as if in a solid form, the emetic might pass from the stomach into the intestines, with- out exciting vomiting. A common practice is to pro- mote the action of emetics by taking large draughts of s tepid water, or of an infusion of chamomile. If an eme- tic is given in a large dose, this is not necessary, as it will excite vomiting repeatedly at intervals; but if given in a moderate dose, it may excite vomiting only once; nausea and efforts to vomit will recur, however, at in- tervals, and then vomiting may be renewed by a draught of tepid water, or of a bitter infusion. We thus obtain the advantages of repeated vomiting, without the risk attending a large dose of a powerful emetic. Too large a draught ought not to be taken, as it renders the ope- ration more difficult or painful. Some acrid emetics, however, as mustard, require always to be largely di- luted. The most natural subdivision of this class is into Emetics from the Vegetable, and from the Mineral Kingdom. Vol. I. 2 H 242 EMETICS. FROM THE MINERAL KINGDOM. Antimonium. Zinc m. Cuprum. Ammonia. HyDRO-SULPHURETUM AMMONIiE. FROM THE VEGETABLE KINGDOM. CALLICOCCA IPECACUANHA. SciLLA MARITIMA. Anthemis NOBILIS. SlNAP S ALBA Asarum EUROPJEUM. NlCOTIANA TABACUM. EMETICS FROM THE MINERAL KINGDOM. Antimonium. Stibium. Antimony. The metal to which this name is appropriated, is pe- culiarly distinguished as an evacuant, and under various forms of preparation furnishes some of our most pow- erful cathartics, diaphoretics, and expectorants. AH its EMETICS. 243 preparations in larger doses act as emetics, and several of t. em are in common use for their emetic power. It is therefore under this class that its general history may be introduced. Antimony, in the modern chemical nomenclature, is the name applied to the pure metal. This metal is found in nature most abundantly combined with sulphur, and to this ore the name of Antimony was once generally given by chemical and medical writers; the epithet Crude being frequently added to distinguish it, when h is melted out from the impurities mingled with it. The ore in this state is now named Sulphuret of Anti- mony, and the simple name Antimony is appropriated to the metal itself. The native sulphuret is of a gray or blue colour, with metallic lustre; it is opaque, and has usually a striated texture. To free it from the earthy matter with which it is mixed, when dug from the vein, it is fused. Its lus- tre is greater the more completely it is purified. The proportions of its principles are various; sometimes they are nearly equal; in other specimens the quantity of metal is larger; and there are some varieties unfit for medicinal use, as containing other metals, particularly lead, and sometimes copper. These have inferior lustre, and a less distinctly striated texture. The pure metal is usually obtained from the ore by melting the latter with iron-filings, the iron combining with the sulphur, while the antimony, being very fusi- ble, is run out. The metal is of a bluish white colour, and plated texture, moderately hard, and very brittle; it melts easily, and is even volatilized by a heat not very intense; it is oxidated by exposure to the air at a tem- perature moderately increased; and in the state of ox- i de, it is capable of combining with the greater number of the acids. The sulphuret of antimony has little activity, and in- deed produces scarcely any sensible effect on the system. Ihe preparations of the metal are much more active 244 EMETICS. and though of very different degrees of strength, retain the same general mode of action, and possess therefore the same medicinal virtues. They do not exert any general stimulant operation on the system, but are always directed in their action to particular parts, so as to occasion some sensible evacuation. The principal general medicinal application of anti- mony in these preparations has been for the cure of febrile affections. It is given either so as to induce vomiting or purging, or sometimes in smaller doses, so as to produce only gentle diaphoresis; and exhibited in either mode in the commencement of the disease, it has been considered as capable of cutting short its progress. The use of James's powder, which is an antimonial, has been extensive with this view, and both it, the emetic tartar, and other antimonials, are still employed. Their efficacy has usually been ascribed to the evacuation they occasion, while others have considered antimony, appa- rently with little reason, as exerting an action specific or peculiar in itself in the cure of fever, and not explica- ble on the known effects it produces. Its administration is not easily regulated with precision, in small doses it often fails in producing the favourable crisis expected from its operation; and in larger doses it is liable to act with violence, and produce evacuations under which the powers of the system have sunk. It is principally in the commencement of fever that advantage is derived; in the more advanced stages, when the state of debility is induced, more hazard attends its employment, and less advantage is to be expected from it. Antimonials have been found to have good effects in intermittent as well as in continued fever, in several of the phlegmasiae and exanthemata, and even in several of the profluvia, probably from their evacuating opeiation. As an emetic, antimony is distinguished by the cer- tainty, extent, and permanence of its operation. The action it excites in the stomach is both more forcible, and continues for a longer time, than that from other EMETICS. 245 emetics, and hence it produces more complete evacua- tion, and occasions in a greater degree all those effects which result from the action of vomiting. Its action is also less local. It is generally extended to the intestinal canal, so as to produce purging, and very frequently to the surface of the body, so as to occasion diaphoresis or sweat. It is used more particularly where the effects of full vomiting are required; but where these are not wished for, more gentle emetics are usually preferred. Of the preparations of antimony, it is necessary to take only a very cursory view, as they are to be more fully noticed in another part of the work. They may be arranged under those in which the metal is combined with sulphur; those in which it is oxidated; and those in which it is brought into a saline state by combina- tion with acids. Of the first, the Levigated Antimony (Antimonium Fraeparatum), which is merely the native sulphuret reduced to a state of mechanical division, is the only preparation. It has been given as a diaphoretic, espe- cially in chronic rheumatism, and in some cutaneous affections, in a dose from fifteen grains to one drachm; but it is so inert and uncertain, that it is now discarded from practice. The oxides of antimony are more active, but they are liable to the inconvenience of being uncertain in their operation, partly perhaps from their activity being de- pendent on the state of the stomach with regard to acidity, partly from the various degrees of oxidation in which they may exist, and which are not easily rendered uniform, and partly too from their state of aggregation. Proust has supposed, that there are only two oxides of antimony, one at the minimum, containing 18.5 of oxygen in 100 parts, the other at the maximum, containing 23 of oxygen. This supposition rests principally, however, on the vague assumption, that metals are susceptible only of two degrees of oxidation. Thenard has, on the contrary, endeavoured to prove, that there are at least 246 EMETICS. six oxides of antimony capable of being distinguished by the proportions of oxygen which they contain; the one in the lowest degree of oxidation, containing not more than 0.02 of oxygen, that in the highest degree containing 0.32; and the others containing intermediate proportions. It may be doubtful whether these degrees of oxidation can be established with perfect precision; but it is sufficiently probable, that antimony may com- bine with very different quantities of oxygen, and that even, like other metals, its degrees of oxidation are indeterminate, when they are not fixed by external cir- cumstances connected with their formation. One other circumstance rendering the composition of the prepara- tions of this class more complicated and variable, is that they are usually obtained by processes performed on the sulphuret of antimony, and hence they frequently retain a portion of sulphur in their composition. The following oxides of antimony retain a place in one or other of the Pharmacopoeias. Oxidum Antimonii Sulphurettum. Sulphu- retted Oxide of Antimony.—Of this there are two varieties, differing in the proportions of their elements, and in the state of aggregation. The first is what used to be named Crocus of Antimony (Crocus Antimonii), what is now named by the Edinburgh College, Oxidum Antimonii per Nitratem Potassae. It is prepared by deflagrating sulphuret of antimony with an equal part of nitrate of potash. The greater part of the sulphur is oxidated, and either dissipated in the state of sulphu- rous acid, or in the state of sulphuric acid remains combined with the potash of the nitre; a brown oxide / of antimony remains, combined, according to Proust, with one fourth of sulphuret of antimony, but which it is more probable is directly combined with a portion of sulphur. It acts as a diaphoretic, emetic, or cathartic, but is so uncertain in its operation that it is never pre- scribed. It serves for the preparation of some other anti- EMETICS. 247 monials, and is now employed by the Edinburgh Col- lege for the preparation of emetic tartar. The second oxide of this family is what is named Oxidum Antimonii cum Sulphure Vitrificatum, for- merly Vitrum Antimonii.—This is prepared by expos- ing sulphuret of antimony to the action of atmospheric air at a high temperature. The sulphur is dissipated, and the antimony oxidated, and by the intensity of the heat the oxide is vitrified. It still retains combined with it a portion of sulphur, or, according to Proust, one ninth of sulphuret of antimony. The oxide which forms its basis, contains, according to Thenard, sixteen of oxygen in one hundred parts. It has always combined with it too a portion of silex, derived from the crucible m which it is melted, this earth probably promoting its vitrification. Its operation is extremely harsh, and at the same time so uncertain, that it cannot be medicinally employed. Oxidum Antimonii Vitrificatum cum Cera.—This is prepared by exposing the powder of the preceding preparation with an eighth part of wax to heat. It is thus rendered milder, probably bv part of its oxygen being abstracted by the carbonaceous matter of the wax. It is a preparation, however, which has no advan- tage, and though once highly celebrated in dysentery, in a dose of from 5 to 15 grains, has been long in dis- use, and might be expunged from the Pharmacopoeias m which it is still retained. m Oxidum Antimo-i Album, formerly named Antimo- nium Calcmatum.- This is prepared by deflagrating sulphuret of antimony with a large quantity of nitrate of potash, (three times its weight), so that the sulphur is en- tirely abstracted, and the metal is saturated with oxygen. This oxide retains also combined with it a portion of the potash of the nitre. The preparation is one compara- tively inactive, and does not excite vomiting in a dose less than a scruple or half a drachm. In smaller doses, it has been used as a diaphoretic in t*ie treatment of fever. 248 EMETICS. Oxidum Antimonii cum Phosphate Calcis, also named Pulvis Antimonialis.—This is prepared by ex- posing to heat sulphuret of antimony and bone-shavings, until they are converted into a gray coloured substance, which is exposed in a crucible to a more intense heat, until it become white. The animal matter of the bones is decomposed, the sulphur of the sulphuret is dissipa- ted, the metal is oxidated, and this oxide remains mixed or combined (part of it being also in a vitrified state,) with the phosphate of lime of the bones. The preparation is similar in composition to the celebrated James's Powder, for which it is designed as a substitute. It acts as a diaphoretic, emetic, or cathartic, according to the dose in which it is administered, and is employed principally as a remedy in fever, to arrest the progress of the disease at its commencement, or afterwards to obtain a favorable crisis. It is given in a dose from 5 to 10 grains, repeated, if necessary, after an interval of five or six hours, until sweat, purging, or vomiting, is in- duced. Its peculiar advantages are, that with a considera- ble degree of activity, it is less harsh in its operation, and more uniform than some of the other antimonial oxides, while from its insolubility, it acts less rapidly on the stomach than emetic tartar does; it is therefore less liable to excite nausea or vomiting, and can be given so as to obtain with more certainty the general action of antimonials on the system. Its exhibition is best adapted to those forms of fever in which there is increased vascular action: in typhus, less advantage can be expected from it, and it is even hazardous from the excessive evacuations it is liable to induce. Sulphurettum Antimonii Praecipitatum.—This name, obviously incorrect, is given by the London and Edin- burgh Colleges to a preparation formerly named Sulphur Auratum Antimonii. The Dublin College have named it Sulphur Antimoniatum Fuscum. It is prepared by boiling sulphuret of antimony with a solution of potash, and adding to the filtered liquor, sulphuric acid, while EMETICS. 249 any precipitate is thrown down. This precipitate is of a reddish yellow colour; it is a combination of oxide of antimony with sulphuretted hydrogen and sulphur. In a dose from 5 to 10 grains, it produces the usual effects of antimonials, and has been employed as a remedy in fever; but from the uncertainty of its operation, it is discarded from practice. The preparation named Kermes Mineral, and which is used on the continent, is the precipitate that subsides on cooling from the liquor formed by the boiling a so- lution of potash on sulphuret of antimony; it differs from the former in containing less sulphur, and appears indeed to be merely a combination of oxide of antimony with sulphuretted hydrogen. It is given in a similar dose. Antimonii Oxidum.—Under this name, which is far from being distinctive, a preparation is inserted in the London Pharmacopoeia, formed by boiling sulphuret of antimony in muriatic acid, with the addition of a little nitric acid; straining the liquor, and adding to it a solu- tion of sub-carbonate of potash. The precipitate is pro- bably a sub-muriate. It is designed to be employed only in the preparation of other antimonials. By combining the oxides of antimony with an acid, the sources of uncertainty in their operation are in a great measure removed, as their degree of oxidation is rendered determinate, and their activity is not influenced by the state of the stomach with regard to acidity. The greater number of these saline combinations, however, are too acrid to admit of internal administration, and there is one only, that in which the oxide of antimony is combined with tartaric acid, employed in practice. Of all the antimonials, this is most extensively used, and it is also the principal emetic derived from the mineral kingdom. This preparation, the Emetic Tartar of the old no- menclature, the Tartrate of Antimony and Potash of Vol. I. 21 250 EMETICS; Modern Chemistry, (Tartras Antimonii et Potassae), improperly named in the Pharmacopoeias, Tartris An- timonii, and Antimonium Tartarizatum, is obtained by boiling super-tartnve of potash with oxide of antimony; the brown oxide obtained by the deflagration of sul- phuret of antimony with nitre, is ordered by the Edin- burgh College; the white oxide, or rather sub-muriate, obtained from the decomposition of muriate of antimony, is employed by the London and Dublin Colleges: the excess of tartaric acid in the super-tartrate, is saturated by the antimonial oxide; and by evaporation and crystal- lization, a triple salt, tartrate of antimony and potash is procured. Its crystals are triedral pyramids, generally small; and it is readily soluble in water. It consists, ac- cording to Thenard's analysis of it, of 38 of oxide of antimony, 16 of potash, 34 of tartaric acid, and 8 of water of crystallization. Tartrate of antimony and potash is superior to all the antimonials, at least as an emetic; as with a degree of activity, which admits of its being administered with safety, its operation is sufficiently certain and uniform. As an emetic, it is establibhed in common practice: it usually excites vomiting in the dose of a grain, or a grain and a half; but the proper mode of administering it is in divided doses, three or four grains being dissol- ved in four ounces of water, and an ounce of tljis solu- tion being given every quarter of an hour, until it ope- rate. It generally excites full vomiting, and is liable to be somewhat more active in its operation than the mild- er emetics, such as ipecacuan, evacuating not only the contents of the stomach, but inverting even the motion of the duodenum, and either by this or by the compres- sion exerted by the action of the muscles on the abdo- minal viscera causing bile to be discharged: it also fre- quently excites purging. In many cases, however, these are advantages, and in these, as well as in all morbid af- fections, where the stomach is not easily affected, it is the emetic properly employed; while, when the stomach EMETICS. 251 is irritable, where its contents are merely to be evacua- ted, or when the strength is exhausted, the milder eme- tics are to be preferred. In smaller doses, it has been employed as a nauseating remedy in fever,—a practice, however, now nearly relinquished. Assisted in its ope- ration by tepid diluents, it may also be brought to ope- rate as a diaphoretic, and to produce the effects of anti- monials on the general system, though from its action being exerted at once on the stomach, owing to its so- lubility, it is more difficult to administer it with this in- tention without occasioning nausea or vomiting, than some of the less active antimonials, as the phosphate of antimony and lime. Vinum Tartritis Antimonii.—This name is given to a solution of tartrate of antimony and potash in white wine, in the proportion of two grains to the ounce, and is intended as a substitute to what was formerly named Antimonial Wine,—a preparation obtained by digest- ing wine on oxide of antimony, and owing its power to the portion of oxide which the tartaric acid of the wine dissolved. A similar preparation is inserted in the Lon- don Pharmacopoeia, under the name of Liquor Antimo- nii Tartarizati, in which the tartrate of antimony and potash is dissolved in wine diluted with water. The propriety of either is doubtful. It has no advantage over a solution of extemporaneous preparation; and there is some reason to believe, that the tartrate in this state of solution is liable to spontaneous decomposition. In the preparation of the London College, this will probably happen still more readily from the dilution of the wine. It is principally as a diaphoretic that antimonial wine has been employed, in a dose of one drachm, its opera- tion being often promoted by combination with tincture of opium. Murias Antimonii.—Muriate of Antimony is the only other saline preparation of this metal inserted in the Pharmacopoeias; and it has a place as affording a pro- duct employed in the preparation of other antimonials. £52 EMETICS. Sometimes it has been applied externally as an escha- rotic. Zincum. Zinc. (Page 177.) Sulphate of Zinc, it has already been remarked, is a powerful emetic; and as it operates speedily, and with much force, it is sometimes employed in cases where it is difficult to excite vomiting, but where it is of importance that the contents of the stomach should be immediately evacuated, where any narcotic poison has been swallowed. Its dose is from 5 to 20 grains, accor- ding to the state of the stomach, and it should be given in a state of solution. Cuprum. Copper. (Page 179.) Sulph ate of Copper acts as an emetic, and its oper- ation taking place almost as soon as it has reached the stomach, and without inducing much nausea, it has been recommended in some cases, where the object is merely to obtain the mechanical effects from the opera- tion of vomiting, as in incipient phthisis, in which ad- vantage has been supposed to be derived from the com- pression exerted on the thoracic viscera. Its operation is, however, liable to be very harsh even in the small dose of I or 2 grains, in which it has been prescribed. In a larger dose, it has sometimes succeeded in pro- ducing vomiting, where the stomach, from the opera- tion of a narcotic poison, had not been affected even by the sulphate of zinc. The acetate or sub-acetate of cop- per has, like the sulphate, an emetic power, and has been employed in similar cases in a dose of one or two grains. It is liable to the same disadvantages. Ammonia.—Ammonia dissolved in water is applied to different medicinal purposes, and under some of the other classes it is to be more fully considered. When given in a pretty large dose, it is liable to excite vomit- ing, and it is sometimes employed to quicken the oper- ation of other emetics where they have failed, a tea- EMETICS. 253 spoonful being given in a cupful of cold water, and a draught of tepid water being swallowed after it. Hydro-sulphuretum Ammonite.—The Hydro- sulphuret of Ammonia obtained by passing a current of sulphuretted hydrogen gas through a solution of ammo- nia in water, was introduced by Dr. RoUo, and has been received into the Edinburgh Pharmacopoeia. It acts with much energy on the stomach, inducing nausea in a small dose, and in a larger dose occasioning vomiting. It is scarcely used as an emetic, but rather as a nausea- ting remedy; and the principal application of it has been in the treatment of diabetes, with the view of reducing the morbid appetite and increased action of the sto- mach. It was given in a dose of from 5 to 15 drops, twice a-day, and with advantage so far as related to the reduction of the increased action of the digestive or- gans. EMETICS FROM THE VEGETABLE KINGDOM. Ipecacuanha. Ipecacuan. Callicocca Ipecacuanha. Cephaelis Ipecacuanha of Wildenow. Pentand. Monogyn. Aggregate. Radix. South America. The natural history of this vegetable is still some- what obscure, and the obscurity is increased by the roots of different plants being sometimes met with in the shops as ipecacuan. Hence the plant affording it has been suc- cessively referred to different genera. It is now, by the Edinburgh and London Colleges, referred to the genus Callicocca, and distinguished as a species by the name Ipecacuanha; but it appears still uncertain, whether the two more common varieties of ipecacuan are products of the same vegetable, the Peruvian and the Brazillian. The former has been even considered as a different spe- cies. The ipecacuan of the shops is usually in small wrinkled pieces, externally gray, internally whiter; has 254 EMETICS. a faint smell, and a bitter, slightly acrid taste. It contains both a resinous and gummy matter, or at least a matter principally soluble in alkohol, and another more soluble in water. It is generally stated, that its emetic power, and indeed its principal virtues, reside in the former. Dr. Irving has affirmed that they depend on the latter. Its active matter is completely extracted by proof spirit or wine. Vinegar likewise dissolves it, but at the same time greatly weakens its power. By decoction with wa- ter, its activity is greatly impaired, though the water dis- tilled from it has scarcely any emetic effect. It is even injured by being kept long exposed in the state of pow- der to the air and light. Ipecacuan is the mildest of those emetics which are at the same time sufficiently certain in their operation. It evacuates the contents of the stomach, without ex- citing violent vomiting, or extending its action beyond this organ; and is hence adapted to many cases where violent vomiting would be prejudicial. The medium dose of it as an emetic is 15 grains, though 20 or 30 may be taken with perfect safety, as it only operates more speedily, and a dose rather large is even preferable to a small dose, as more certain, and producing less nausea. The ipecacuan wine acts as an emetic in the dose of an ounce. Though principally employed as an emetic, ipecacuan is occasionally prescribed with other views. It was originally introduced as a remedy in dy- sentery, given either in such a dose as to produce full vomiting, or in the quantity of 2 or 3 grains repeated every three or four hours, till it occasioned vomiting, diaphoresis, or purging. It has been given in a similar mode in obstinate diarrhoea. In spasmodic asthma, it is exhibited in a full dose to relieve the paroxysm; and in a dose of 3 or 4 grains continued every morning for some weeks to prevent the disease. A singular idiosyn- crasy has been observed in some individuals with re- gard to it, difficulty of breathing being induced by the effluvia arising from it in powder, especially when it is diffused in the air. In hzemorrhagies it is given in EMETICS. 255 nauseating doses, the nausea diminishing the force of the circulation. Combined with opium, it forms a very powerful sudorific. Offic. Prep.—?. Ipecac, et Opii. Vin. Ipecac. Edin. Lond. Scilla maritima. Squill. Hexand. Monog. Liliacee. Radix. South of Europe. Squill is the bulbous root of a plant growing on the sandy shores of Spain and Italy. It has little smell; its taste is bitter and acrid, and it is capable of inflaming the skin; its acrimony is lessened by drying; but its bit- terness and active powers as a medicine are little im- paired. In drying it loses about four-fifths of its weight. Its active matter is extracted by water, alkohol, and vinegar. The latter is the solvent commonly employed, as it best covers its nauseous taste, and it does not ap- pear to injure its powers. Squill, when given in a sufficient dose, excites vomit- ing, though it is seldom used with that intention in sub- stance. The vinegar of squill acts as an emetic in a dose of 2 or 3 drachms, as does the syrup when given in double that quantity; and either of them is sometimes given in pertussis; the syrup, in particular, from its sweetness, being easily given to children. The dose is a drachm to a child below five years of age, and its acti- vity is advantageously promoted by the addition of a little ipecacuan wine. This root is, however, much more used as a diuretic and expectorant; uses of it which are afterwards to be noticed. Offic. Prep.—Acet. Scill. Mar. Pil. Scill. Syr. Scill. Mar. Ed. Lond. Dub.—Tmct. Scill. Lond. Drub. Anthemis nobilis. Chamomile. (See p. 200.) All bitter drugs are liable to excite nausea or vomit- ing. Chamomile has perhaps more peculiarly this effect; a strong infusion of the dried flowers in tepid water ex- cites vomiting, and a weaker infusion is often employed to quicken the action of other emetics, a draught of it being taken instead of tepid water. 256 EMETICS. Sinapis alba. Mustard. Tetradyn. Silig. Siloquose. Semen. Indi- genous. Mustard-seed, when bruised, has a very conside- rable degree of pungency, and in powder, given in the dose of a large tea-spoonful, mixed with water, operates as an emetic. From its stimulant quality, it has been re- commended in preference to other emetics in apoplexy and paralytic affections, and in such cases has sometimes been found to excite vomiting, when these had failed. It is convenient also as an auxiliary, when the dose of an emetic has not operated, a little of the powder of mus- tard being taken diffused in tepid water. Asarum Eunoi'.su ,'. Asarubt-cca- Dodecand. Monogyn. Sarmen- tacee. Folia. Indigenous. The leaves and root of this vegetable, prior to the in- troduction of ipecacuan, were frequently employed on account of their emetic quality; the dose of the dried leaves was 20 grains: of the dried root, 10 grains. As they were occasionally violent in their operation, and at the same time uncertain, they have fallen altogether into disuse. The plant is still retained in the Materia Medica as an errhine. Nicotiana tabacum. Tobacco. (See p. 143.) The leaves of this plant, in a person unaccustomed to their use, by chewing, or smoking, excite even in a small dose very severe and permanent nausea and vomit- ing: the same effects have followed even from their ex- ternal application to the region of the stomach; and this method of exciting vomiting has been proposed to be employed in cases in which emetics cannot be easily ad- ministered by the mouth. Tobacco is sometimes taken under the form of infusion by the common people, but its operation is always harsh, and accompanied with se- vere sickness. 257 CHAPTER VIII. OF CATHARTICS. Cathartics are those medicines which quicken or increase the evacuation from the intestines; or which, when given in a certain dose, produce purging. They are medicines of considerable importance, and differ from each other very considerably in their powers. Cathartics evidently act, by stimulating the intestines so as to increase the natural peristaltic motion. Their contents are thus more quickly propelled and evacuated. The greater number, or perhaps all of them, have how- ever a farther effect. They stimulate the extremities of the exhalant vessels, terminating on the inner surface of the intestines: they thus cause a large portion of fluid to be poured out, and hence the evacuations are more co- pious, and of a thinner consistence. Some cathartics have this power of increasing the effusion of fluids from the exhalants much more than others, such for instance are the Saline Purgatives. Dr. Cullen has even supposed that some may act solely in this way, and without in- creasing directly the peristaltic motion. There is, how- ever, no proof of this; and it seems scarcely probable that any substance should act as a stimulant on these vessels, without at the same time stimulating the moving fibres of the intestines. The action of cathartics is not confined to the parts to which they are directly applied. Their stimulus is extended to the neighbouring organs, and hence they promote the secretion, and increase the discharge of the bile and other fluids usually poured into the intestinal canal. These effects are produced in very different de- grees, by different cathartics, and there seems some reason for admitting an opinion adopted by the ancients, that certain cathartics have peculiar powers, in this re- spect; some, for instance, having the power more parti- Vol. h 2K1 258 CATHARTICS. cularly of promoting the discharge of bile, others that of the mucus of the intestines, or of the serum; and it is not improbable, adds Dr. Darwin, that the pancreas and spleen may be peculiarly stimulated into action, by some others of this class of medicines. There is likewise a difference in cathartics with re- spect to the parts of the intestinal canal on which they act. Some increase its peristaltic motion through its whole length; others, as aloes, have their action more confined to the lower part, and principally to the rectum. Lastly, it is to be observed, that the action of many cathartics is extended even to the stomach; its peristal- tic motion is increased, either from association with the motion of the intestinal canal, or from the action of the stimulus of the cathartic applied, and its contents are therefore more quickly discharged by the pylorus. From this cause, a full dose of a saline purgative will sometimes operate in half an hour after it is given. There are several other differences between the me- dicines belonging to this class: some act slowly; others more quickly: some are liable to occasion nausea and griping, and in a large dose tenesmus; others, even when they operate effectually, are free from these disa- greeable effects: some produce only one evacuation, others continue to act for a considerable time. Besides the differences between particular cathartics, a general difference in their mode of operation has been supposed to exist, from which they have been classed under two divisions. Some operate mildly, without exciting any« general affection of the system, without even stimulating perceptibly the vessels of the intes- tines, and hence they merely evacuate the contents of the canal. Others are more powerfully stimulant: they occasion an influx of fluids from the exhalant vessels, and from the neighbouring secreting organs: they even extend their stimulant effect to the system in general, and if taken in too large a dose are liable to excite much irritation, and even inflammation on the surface of the intestines. The former are distinguished by the CATHARTICS. 259 title of Laxatives, the latter are named Purgatives, and the stronger of them Drastic Purgatives. The distinc- tion is not altogether correct, since it refers merely to a difference in power; yet neither is it one to be alto- gether neglected. From the indications which cathartics are capable ol fulfilling, their utility in many cases of morbid affection must be obvious. In some general affections of the sys- tem, they procure a prompt, copious, and therefore use- ful depletion. And wherever there exists retention of the contents of the intestinal canal, where these contents are acrid, or where extraneous bodies are present, their evacuation by the operation of a cathartic is the ob- vious method of treatment. The valuable observations of Dr. Hamilton have esta- blished, however, still more clearly the importance of this class of remedies, have shown that they admit of more extensive application, and have pointed out with more precision than has hitherto been done, the princi- ples which regulate their administration. In many diseases, there exists a state of the intestinal canal giving rise to retention of its contents, which is not to be obviated by the occasional administration of a cathartic, but which requires a continuation of the ope- ration short of that of purging, until the healthy state of the bowels be restored. By this practice the cure of diseases has been accomplished, which, previously to Dr. Hamilton's publication, were treated by very dif- ferent methods, and were not supposed to be so pecu- liarly connected with any state of the alvine evacuation. Thus in fever, the peristaltic motion of the intestines is diminished, the faeculent matter is retained, and be- comes a source of irritation; its evacuation, therefore, by the exhibition of purgatives is clearly indicated, nor has this been altogether neglected. Physicians, how- ever, were scarcely aware of the necessity of producing it to a sufficient extent; and in fevers of the typhoid type in particular, were frequently deterred from doing so by the fear of reducing the strength of the system by 266 CATHARTICS. an evacuation considered as debilitating. Dr. Hamil- ton's observations establish the propriety of the freer use of purgatives in fever, so as to produce complete and regular evacuation of the bowels, through the whole progress of the disease; and the cases he has published afford striking proofs of the advantages de- rived from the practice. It is attended with equal advan- tage in scarlatina. Several of the diseases comprehended under the class Neuroses appear to depend on, or to be very intimately connected with a torpid state of the intestines, from which an accumulation of their contents takes place, proving a source of irritation that often affects the gene- ral system. Chorea is proved by Dr. Hamilton's obser- vations to arise from this cause; and he has introduced with great success the mode of treatment, by the free use of purgatives, continued until the healthy state of the alvine evacuation has been established. The same practice, and with similar success, applies to hysteria, and, in Dr. Hamilton's opinion, to that species of teta- nus, which, prevailing in warm climates, and in warm seasons, appears to have its origin in disorder of the stomach and bowels. An ample evidence has establish- ed the success of the same treatment in the marasmus which attacks the young of both sexes, which is mark- ed by loss of appetite, weakness, wasting of the body, and at length total prostration of strength; likewise in chlorosis, and in that hasmatemesis to which females are liable between eighteen and thirty years of age. In some of these diseases, the quantity of matter accumu- lated in the intestines is extremely great; the extent to which the exhibition of purgatives must be carried, and the length of time during which they must be continued, much exceed what would be calculated on from the usual administration of remedies of this class. The whole practice requires therefore both decision and perseverance. Analogies from some of these diseases lead to a simi- lar exhibition of cathartics in other fevers, particularly in CATHARTICS. 261 the bilious remitting fever of warm climates, in measles, erysipelas, and small pox; likewise in scrofula, in dys- pepsia, whether simple, or complicated with hysterical or hypochondriacal mania; in cramp of the stomach, or of the extremities; in palpitation of the heart, and in those cases of hydrophobia which are not the effect of specific contagion. With regard to several of these, ex- perience has established the soundness of the analogy. In colic, and in ileus, the exhibition of cathartics is required, though there is considerable caution necessary in their application to avoid such irritation as would excite or increase inflammation. In dysentery, similar advantages are derived from them, and the same caution is requisite in their use. Cathartics are farther employed with other intentions than merely to evacuate the intestinal canal. From the effusion of serous fluid which they occasion, by their stimulant action on the exhalant vessels, they are sup- posed to produce a diminution of fluids with regard to the whole body. This is in some measure an abstraction of the usual exciting powers acting on the system, and hence purging constitutes a part of what is named the Antiphlogistic Regimen, and is employed in inflamma- tory affections. By a similar operation, it increases absorption. There exists a certain relation between the exhaling and absorbing powers, so that when the action of the one is increased, that of the other is augmented: the increased exhalation of serous fluid, therefore, into the intestines, which cathartics occasion, causes an in- creased absorption; and thus the different species of dropsy are often cured by purging. It is evident that those cathartics which stimulate the exhalant vessels are best calculated to fulfil this indication; hence saline purgatives are in general most serviceable in dropsy. Partly, it is supposed, from the serous evacuation which cathartics occasion, and partly on the derivation which they make from the head, and partly, no doubt, by removing a source of irritation, cathartics are of utility in preventing and removing apoplexy; in all 262 CATHARTICS. comatose affections, in mania, phrenitis, and the differ- ent species of headach. Cathartics, especially the more powerful ones, require to be administered with caution even in diseases where they are indicated, by peculiar circumstances, particu- larly any tendency to inflammation or to extreme debi- lity; also during pregnancy, immediately after delivery, during the flow of the menses, and in those liable to haemorrhoidal affections. The too frequent use of them induces wasting of the body, and sometimes renders the intestines morbidly irritable, so that purging is easily excited, while in other habits it renders them more torpid, and induces costiveness. Some cautions are requisite with respect to the mode of administering cathartics. Many of them are apt to excite nausea or vomiting,—effects which are prevent- ed by giving them at intervals in divided doses, or often by combining them with some aromatic. Such a com- bination also obviates the griping which they often occasion. The more active cathartics ought always to be given in divided doses; as in certain habits, even a small dose is liable to occasion unpleasant symptoms. In general also, these acrid cathartics ought to be given rather in combination, as the effect is obtained with more certainty. Colocynth, or scammony, or any other drastic purgative, may fail if given alone in such a dose as it is proper to venture on; but if smaller doses of two or three of them be mixed, their operation is more cer- tain and easy. They irritate less when given in a liquid form: in that form too they act more speedily than when given in a solid state: hence, when we wish a cathartic to operate slowly, it is best given in the form of pill, and at bed time, as the state of diminished susceptibility in sleep retards the operation. In general, however, it is preferable to give the dose of a cathartic in the morning, as the operation of it is less troublesome to the patient. Dr. Hamilton has pointed out the common error in the exhibition of cathartics, that of their not being given to the requisite extent; and given the general rule in all CATHARTICS. 263 morbid affections, of repeating, and, if necessary, en- larging the dose while the evacuations remain offensive, or of an unnatural appearance, without however carry- ing their administration so far as to produce purging, unless this be the indication which is designed to be fulfilled. Cathartics may be arranged in some measure accord- ing to their power, placing those first which operate mildly, and which have usually been denominated Laxa- tives, and proceeding to those which are more powerful, and have other effects than merely evacuating the con- tents of the canal. The Saline Cathartics may be placed under the latter division, though their operation, as has been already explained, is somewhat peculiar. To the class may also be added those substances which act as cathartics under the form of Enema. 264 CATHARTICS. A—LAXATIVES. Manna. Cassia fistula. Tamarindus indica. RlCINUS COMMUNIS. Sulphur. Magnesia. B.—PURGATIVES. Cassia senna. Rheum palmatum. convolvolus jalapa. helleborus niger. Bryonia alba. cucumis colocynthis. momordica elaterium. Rhamnus catharticus. Aloe perfoliata. convolvolus scammonia. Stalagmitis cambogioides. sub-murias hydrargyri. Sulphas magnesia. Sulphas sodje. Sulphas potassje. super-tartras potass.e. TARTRAS POTASSiE. TARTRAS POTASS^E ET SODJE. Phosphas SODiE. murias sod.s. Tbrebinthina veneta. NlCOTIANA TABACUM. CATHARTICS. 265 LAXATIVES. Manna. Manna. Fraxinus Ornus. Fraxinus Rotundifolia. Polygam Dicec. Ascyroid. Succus concretus. South of Europe. This substance, though afforded by several vegeta- bles, is usually obtained from different species of the ash-tree, particularly those mentioned above, which are cultivated in Sicily and Calabria. It is procured by spontaneous exudation, but more copiously by inci- sions made in the bark of the trunk. The juice, which exudes, soon becomes concrete. When it exudes slowly, the manna is more dry and white, and of a texture some- what granulated, forming what is named Flake Manna. When the exudation is more copious, the juice is of a darker colour, and concretes into a soft unctuous-like mass, less pure than the other. Manna has a sweet, though somewhat unpleasant taste, and possesses the general chemical properties of saccharine matter; it is entirely soluble in water and alkohol. The chemical difference between it and pure sugar is not very well established. When dissolved in alkohol, with the aid of heat, the solution on cooling de- posites crystals apparently purely saccharine; and by concentration of the residual liquor, a mucilaginous ex- tractive matter remains not crystallizable, having the peculiar taste of the manna. Although sugar in its unrefined state proves laxative, manna is so in a greater degree. The dose of manna, as a laxative, is from one to two ounces to an adult, but it scarcely operates with suffi- cient effect to admit of being employed alone. Though mild in its operation, it is apt to produce flatulence and griping, and hence it is principally used in combination with other cathartics, particularly with senna, the bitter taste of which it covers. This combination is in common use as a purgative to children. Offic. Prep.—Syrup. Mannas. Pharm. Dub. Vol. I. 2 h 266 CATHARTICS. Cassia fistula. Purging Cassia, or Cassia in pods. Decand. Monog. Lomcntacce. Fructus; Pulpa Fructus. Egypt; East and West Indies. The fruit of this tree is in pods, nearly an inch in diameter, and ten or twelve in length. The external membranous part is firm and hard, the pulp within is of a black colour, and has a sweet taste, with a slight de- gree of acidity. It is extracted by boiling the bruised pods in water, and evaporating the decoction. It is so- luble in water. According to Vauquelin's analysis of it, it contains, besides the fibrous part, gluten, jelly, mucilage, and saccharine matter. This pulp proves gently laxative in a dose of four or six drachms; in the large dose necessary to occasion purging, it is apt to induce nausea or griping, and even as a laxative it has no particular advantage. The sole consumption of it is in the composition of the officinal preparation known by the name of Electuarium Sennas. There is another electuary in the Pharmacopaeias, to which, as being the principal ingredient, it gives its name, and in which it is combined with manna and pulp of tamarinds, but this is never used. Offic. Prep.—Elect. Cass. Fist. Ed. Lond. Dub. Tamarindus indica. Tamarind. Monadelph. Triand. Lomen- tacee. Fructus conditus. East and West Indies, America, Arabia. The pod of this tree includes several large hard seeds, with a brown viscid pulp, very acid. This pulp, mixed with the seeds and small fibres, and with a quantity of unrefined sugar added to preserve it, forms the Tama- rinds of the shops. Vauquelin found it to contain, be- sides the sugar mixed with it, citric and malic acids, super-tartrate of potash, tartaric acid, jelly, mucilage, and fibrous matter. The pulp of tarmarinds, besides its virtues as an acid, proves laxative, when taken to the extent of an ounce, or an ounce and a half, but it is too weak to be employed alone. It is generally added to other cathartics, which are CATHARTICS. 267 given in the form of infusion, with the view of promot- ing their operation or of covering their taste. It is an ingredient in the Electuanum Sennae, and there is an officinal infusion of it with senna, which affords a very pleasant purgative. Offic. Prep.—Inf. Tam. Ind. cum Cass. Sen. Ed. There are some other sweet fruits which have a laxative quality, as the Fig (Ficus Carica,) and the Prune (Prunus Domestica). These are sometimes used in domestic practice, and they are also ingredients in the Electuary of Senna. Ricinus communis. Palma Christi. Moncec. Monadelph. Tricocee. Oleum; Semen. West Indies. The seeds of the capsules of this plant are farina- ceous, with a considerable quantity of unctuous matter intermixed. They afford, by expression or decoction, an oil which is used in medicine in this country under the name of Castor oil. When obtained by decoction of the bruised seeds in water, it is purer and less acrimo- nious than when obtained by expression. It is of a yellowish colour, and has scarcely any peculiar taste or smell. It is the only example of an expressed oil having any medicinal activity. As a laxative, castor oil acts mildly, and at the same time very effectually; it also operates in a shorter time than almost any other cathartic. Possessed of these ad- vantages, it is a cathartic frequently employed; and is more peculiarly adapted for exhibition, where any de- gree of irritation is to be avoided. Its dose is one ounce. It is taken floating on peppermint-water, mixed with any spiritous liquor, or any purgative tincture, as that of senna; or diffused in water by the medium of gum, sugar, or the yolk of an egg. 268 CATHARTICS. From the Mineral Kingdom, two laxatives, are derived, Sulphur and Magnesia. Sulphur is an inflammable substance, found in nature nearly pure, and likewise in combination with several of the metals. The greater part of the sulphur of com- merce is the produce of volcanic countries. It is natu- rally mixed with earthy matter, from which it is freed by sublimation, forming the Sulphur Sublimatum, Flores Sulphuris, or Flowers of Sulphur. When melted and run into cylindrical molds, it forms Roll Sulphur, which is usually less pure. Sulphur is of a light yellow colour; is insipid; has a faint smell, when rubbed or heated; is very fusible and volatile; and when heated in atmospheric air, burns with a blue flame, and the production of suffocating fumes. It is insoluble in water or alkohol, but is dissolved by oils, and combines with the alkalies, several of the earths, metals, and metallic oxides. It was, until lately, regard- ed as a simple substance; there is reason to believe, however, that it contains hydrogen, and that the pure inflammable base has not yet been obtained. Sulphur, in a dose of 2 or 3 drachms, acts as a laxative, and so mildly, that it is often used in haemorrhoidal af- fections, and in other cases where, though the operation of a purgative is indicated, any irritation would be in- jurious. It likewise passes off by the skin, and is ad- ministered internally, and is applied externally in psora. In habitual dyspnoea and in chronic catarrh, advantage has been derived from it, probably partly from its action as a laxative, and partly as a diaphoretic. The solution of it in oil has been used in these cases, but this pre- paration is both acrid and extremely nauseous. Sulphur is always best given in the form of electuary. The puri- fication of sulphur by washing is ordered in the Phar- macopoeias, but is a process altogether unnecessary. Precipitated by an acid from its solution by an alkali or lime, it is obtained of a whiter colour than in its usual state, and this precipitated sulphur is used in preference CATHARTICS. 269 to the sublimed sulphur in forming ointments. The combination of it with potash, Sulphurettum Potassse, has also been introduced into the Pharmacopoeias, prin- cipally with the view of affording a substance which has been supposed capable, by its chemical action, of coun- teracting the operation of metallic preparations where these have been taken in excess. Offic. Prep.—Sulphur Lotum. Ol. Sulph. Ung. Sulph. Ph. Ed. Lond. Dub.—Sulph. Prsecipit. Ph. Lond.—Sulph. Potass. Ed. Dub. Magnesia is a simple earth, not found pure in na- ture, but existing abundantly combined with certain acids, and from these saline combinations it is obtained by processes to be afterwards noticed. Either pure or in the state of carbonate, it is used as an antacid and laxa- tive, in a dose of a drachm or more. Its laxative effect is generally considered as owing to its forming with the acid in the stomach a saline combination, which, like its other salts, is purgative, though, as it generally has this effect, it probably has itself a weak cathartic quality. From being insipid and mild, it is well adapted for exhi- bition to infants. PURGATIVES. Cassia senna. Senna. Decand. Monog. Lomentacee. Folia. Egypt, Arabia. The dried leaves of this plant are of a yellowish green colour; have a 'faint smell, and a bitter taste. Their active matter is extracted both by water and alkohol by infu- sion. By decoction with water, its activity is much im- paired. Senna is a purgative very frequently employed, having a considerable degree of activity, without being liable to be violent in its operation. It is usually given in the form of the watery infusion, 2 drachms being infused in 270 CATHARTICS. 4 or 6 ounces of tepid water generally with the addition of a few coriander seeds, to cover its flavour, and obviate griping. It is also frequently combined with manna, with tamarinds, or with super-tartrate of potash; and as its taste can be covered by sugar or manna, it is a purga- tive very generally given to children. There is an offi- cinal tincture of it which operates as a purgative in the dose of an ounce; there are also officinal infusions of it; and it enters into the composition of several other pre- parations employed as cathartics. Offic. Prep.—Elect. Cass. Senn. Extr. Cass. Senn. Inf. Tarn. Ind. cum Cass. Sen. T. Cass. Senn. C. Ed. —Inf. Senn. Pulv. Senn.C. Lond.—Syrup. Senn. Lond. Dub. Rheum palmatum. Rhubarb. Enneand. Trigyn. Oleracee. Radix. Tartary. Besides the Rheum Palmatum, two other species, the Rheum Undulatum, and Rheum Compactum, are cultivated with the view of obtaining their roots, to be used in medicine; nor is any considerable difference, it is said, to be observed between the root obtained from any of them when it is properly dried and preserved. The best rhubarb is that named Russian or Turkey; it is in small pieces, with a large hole in the middle; of a lively yellow colour, with streaks of white; has a smell peculiar, and somewhat aromatic; and a bitter slightly styptic taste. Another kind is imported from the East Indies, or rather from China, in larger masses, more compact and hard, heavier, less friable than the other, and having less of an aromatic flavour. Rhubarb, cultivated in this country, has been prepared equal to either of the others, but in general it is inferior, probably from less care being be- stowed on its cultivation and preparation. The active principles of rhubarb are not very well ascertained. It is somewhat mucilaginous, and yields part of its powers to water by infusion. Alkohol like- wise dissolves a considerable proportion of it; and di- luted alkohol appears to be its most proper solvent, CATHARTICS. 271 dissolving all its active matter. It appears too to contain a portion of tannin, as it gives a deep colour with the salts of iron. It has the combination, rather singular, of an astringent with a cathartic power; and it does not ap- pear, from any analysis of it, whether these reside in different proximate principles or not. The watery infu- sion is said to be more purgative than the spiritous, and by applying heat to the rhubarb in substance, its purga- tive quality is lessened, while its astringency remains. The Chinese rhubarb is supposed to be more astringent than the Turkey. Every kind of it contains a quantity of earthy matter, chiefly lime, combined with sulphuric and citric acids, forming the principal part of the white streaks. This is generally more abundant in the Turkey rhubarb than in the others. The dose of rhubarb as a cathartic is one scruple or , half a drachm. Along with its purgative operation, it exerts a moderately astringent power, and has hence been considered as peculiarly adapted for exhibition in diarrhoea, any acrid matter being evacuated before it acts as an astringent. From the conjunction of bitterness with these qualities, it is likewise often used in dyspepsia and hypochondriasis, to obviate costiveness. And it en- ters into a number of officinal preparations, in which it is either the principal medicine, or combined with aloes, bitters, or aromatics. Offic. Prep.—Inf. Rhei P. T. Rhei P. Ed. Lond. Dub.—Y'm. Rhei. T. Rhei et Aloe. Tinct. Rhei et Gent. Pil. Rhei. C. Ed.—Tinct. Rhei, C. Extr. Rhei, Lond. Convolvolus jalapa. Jalap. Pentand. Monogyn. Campanacee. Radix. Mexico. The dried root of jalap is imported in thin transverse slices; it is solid, hard, and heavy; of a dark gray colour, and striated texture. It has little smell; its taste is bitter and subacrid. Jalap contains a resinous and a gummy matter, its purgative quality appearing to reside in the former, as it is extracted by alkohol, while its watery infusion is com- paratively inert. Proof-spirit is its proper menstruum. 272 CATHARTICS. This root is an active purgative, producing full eva- cuation from the intestines; sometimes occasioning, however, nausea or griping. Its medium dose is half a drachm. Besides being given alone, it is very frequently used to quicken the action of other cathartics, of mild muriate of mercury for example; or it is combined with others, which are supposed to render it less stimulating, as with the super-tartrate of potash. It operates most mildly and effectually in substance, and is therefore sel- dom given under any form of preparation. Offic. Prep.—T. Conv. Jal. Ed. Lond. Dub.—Extr. Cbnv. Jalap. Ed. Dub.—Pulv. Jalap. C. Ed. Helleborus niger. Melampodium. Black Hellebore. Polyand. Polygn. Multisilique. Radix. Austria, Italy. The root of this plant consists of short articulated fibres attached to one head, externally dark-coloured, in- ternally white. Its taste is very acrid, but the acrimony is much impaired by drying and by age. Its active power seems principally to reside in its resinous part. By decoction with water it yields half its weight of gum- my matter, with some resin; and the extract obtained by inspissation of this, is milder than the root itself. Its distilled water, it is affirmed, is acrid, and even cathartic. Black hellebore root is a very powerful cathartic, so violent, indeed, and at the same time uncertain in its operation, that it is scarcely ever used in substance: the watery extract of it, which is milder, has sometimes been employed. On its cathartic power probably de- pends any advantage that may be derived from its ad- ministration in mania and melancholia, in which dis- eases it was highly celebrated by the ancients. In dropsy it has been employed as a hydragogue cathartic, princi- pally under the form of the spiritous extract. It was likewise strongly recommended by Mead as an emme- nagogue, in the form of tincture, but with others has seldom been successful. Offic. Prep.—T. Helleb. N. Ed. Lond. Dub___Extr. Helleb. Ed. Dub. CATHARTICS. 273 Brtonia alba. Bryony. Moncec. Syngenes. Cucurbitacee. Radix. Indigenous. The root of this plant, when recent, is highly acrid; by drying it becomes milder. In a dose of 20 grains of the dried root, it acts as a strong cathartic, and generally also as a diuretic. It is, however, somewhat uncertain, and liable to be violent in its operation, and is therefore little used. Cucumis colocynthis. Colocynth. Moncec. Syngenes. Cucurbi' tacee. Fructus pulpa. Syria. The part of this plant used in medicine, is the dried spongy or medullary part of the fruit. It is white, soft and porous, and has the seeds, which are comparatively inert, mixed with it. Its taste is intensely bitter. Boiled in water, it gives out a large portion of mucilage, less active than the colocynth itself. Alkohol also dissolves only part of its active matter. Colocynth is one of the most drastic purgatives, so much so that its operation is not easily regulated. Its dose is from 3 to 6 grains, but it is seldom that it is given by itself, being rather used to promote the ope- ration of other cathartics. Combinations of it with jalap, aloes, or mild muriate of mercury, are thus given in obstinate constipation, in mania, and coma, and in these combinations it operates more mildly and more effec- tually than if given alone. Its infusion has been recom- mended as an anthelmintic. Offic. Prep.—V\\. Aloes cum Colocynth. Ed.—Extr. Colocynth. Lond.—Extr. Colocynth. Comp. Lond. Dub. Momordica elaterium. Wild Cucumber. Monac. Syngenes. Cucurbitacee. Fecula Fructus. South of Europe. The expressed juice of the fruit of this plant depo- sites a fecula, which when dried, has been known by the name of Elaterium. It is a very powerful cathartic, and from the violence of its operation has been ventured to be exhibited only in the most obstinate cases. Its dose is half a grain, repeated everv hour, or everv se- Vol. I. 2M 274 CATHARTICS. cond hour, till it operate. As a hydragoguc cathartic, it has sometimes been given in dropsy. Rhamnus catharticus. Buckthorn. Pentand. Monogyn. Dumose. Baccarum succus. Indigenous. The berries of this vegetable are very succulent, and the juice they afford by expression has a cathartic power. Made into a syrup by boiling with sugar, it operates in a dose of an ounce. It is disagreeable, however, in its operation, being liable to occasion thirst and griping, and is seldom used. Offic. Prep.—Syr. Rhamn. C. Ed. Lond. Aloe. Aloe Socotorina. Aloe Barbadensis. Aloes Socotorine, and Barbaboes. Aloe Perfoliata, et Spicata. Hex and. Monogyn. Li- liacee. Succus spissatus. Africa, Asia, America. Aloes is a concrete resinous juice. Several varieties of it are met with in the shops, which differ in their pu- rity, and likewise in their sensible qualities. The Soco- torine, brought from the African island of Socotora, is considered as the purest. It is in small pieces of a red- dish-brown colour. The Barbadoes aloes is in large masses, of a lighter colour, and having an odour much stronger, and more unpleasant than the former. It is also named Hepatic Aloes. The Cabbaline is still more impure, more foetid, and is weaker in its power. There is still some uncertainty with regard to the species pro- ducing these varieties. The Aloe Perfoliata is that refer- red to by the Edinburgh College, as affording the varie- ties both of hepatic and socotorine aloes. The Dublin College refer to the Aloe Spicata, and it is said to be this species which is a native of the Cape of Good Hope, whence much of the aloes of the shops is imported. The London College give the same species as that which affords the Socotorine Aloes; while the Barbadoes Aloes, on the authority of Sibthorp, they consider as the produce of a species named Aloe Vulgaris. The Socotorine aloes is the inspissated expressed juice of the leaves of the plant. The Barbadoes aloes is pre- CATHARTICS. 275 pared by cutting the plant, and boiling it in water. The liquor is evaporated to the consistence of honey, and is run into large gourd shells, in which it becomes concrete. The taste of all the kinds of aloes is intensely bitter; their odour disagreeable. They consist of extract and resinous matter, the former being in larger quantity; the latter, obtained by the action of alkohol, has little smell or taste. Diluted alkohol dissolves all the active matter of this concrete juice. Aloes, as a cathartic, has some peculiarities. It is more slow in its operation than any other purgative; it merely evacuates the contents of the intestines, and no greater effect is obtained from a large dose than from one comparatively moderate. These have been regarded as proofs, and perhaps justly, that its operation is prin- cipally on the larger intestines. Its medium dose is 10 grains. As a purgative, it is often employed to obviate habitual costiveness, and it is often combined with other cathartics to produce more complete evacuation. From the supposition of its stimulant operation being more particularly exerted on the rectum, it has been supposed to have a tendency to occasion haemorrhoids,—an opi- nion for which there does not appear much foundation. On the supposition too of its stimulating effect being extended to the uterus, it has been regarded as a pur- gative to be avoided during pregnancy, and on the same hypothesis it has been supposed to exert an emmena- gogue power. Offic. Prep.—P\\. Aloes. Pil. Al. cum Assafoet. Pil. Aloes cum Colocynth. P. Aloes cum Myrrh. T. Aloes jEth. T. Aloes cum Myrrh. Vin. Aloes Socc. Ed.__ Pil. Aloes cum Zingib. Pulv. Al. cum Canella. Pulv. Al. cum Guaiac. Ph. Dub—Pulv. Aloes Comp. T. \loes C. Decoct. Aloes. Extract Aloes. Lond. 276 CATHARTICS. Convolvolus scammonia. Scammony. Pentand. JMonogyn. Cam- panacee. Gummi-resma. Syria. Scammony is obtained by cutting the root of the plant, and inspissating the juice which exudes, by ex- posure to the sun and air. It is in bmall fragments, of a blackish gray colour, having little smell, and a bitter sub- icrid taste. It is however variable in i;s quali'ies and is often adulterated by the intermixture of earthy matter. It is one of what are namtd Gum resins, and consists of resin and gum in general nearly in equal proportions. Scammony is one of the most drastic purgatives, and is employed chiefly where the less powerful substances of this class would fail. Its dose is from 5 to 10 grains, but it is generally combined in a smaller dose with other cathartics. It is also used as a hydragogue purgative in dropsy, combined usually with super-tartrate of potash. Offic. Prep.—Pulv. Scamm. C. Ed.—Pulv. Scamm. C. Confect. Scamm. Lond. Gambogia. Gamboge. Stalagmitis Cambogioides. Polyand. Monoec. Tricocce. Gummi-resina. India. This gum-resin is obtained by exudation, from in- cisions made in the branches and trunk of the tree. It is brittle, of a lively yellow colour, and resinous frac- ture, has a taste bitter and acrid. Water and alkohol partially dissolve it, and its solution in alkohol becomes turbid on the addition of water. Gamboge is a very powerful cathartic, liable in large doses to excite vomiting, or to act with \ iolence, and occasion profuse evacuations, with griping and tenes- mus. Its medium dose is from 2 to 6 grains. It is sel- dom employed but in combination with some of the other powerful cathartics, in obstinate constipation. It is also used to expel the tape-worm, and as a powerful hydragogue cathartic in dropsy In the latter application of it, it is frequently combined with super-tartrate of potash. Offic. Prep.—Pil. Gambog. Comp. Ph. Lond. CATHARTICS. 277 Mumas hydrargyri. mitis. Calomelas. Mild Muriate of Mer- cury. Calomel. SuW-muriate of Mercury of the London and Edinburgh Pharmacopoeias. Thouoh several of the preparations of mercury have a degree of cathartic power, this is most evident in the mild muriate; and this preparation is even in common use as a cathartic. It operates as such, when given alone in a dose of from 5 to 10 grains, but with more cer- tainty and power when its operation is promoted by the addition of a little jalap or rhubarb. One valuable qua- lity which it has, is that of promoting the operation of other cathartics, without exciting any additional irrita- tion, or rendering them liable to act with violence; it is therefore, in more obstinate cases, combined with colo- cynth, scammony, or gamboge; and such a combination affords the safest of the powerful cathartics. A division of Cathartics remains, intermediate in their operation between the Laxatives and Purgatives, more powerful than the one, less acrid and stimulating than the other. These are the Neutral Salts. They appear to act principally by stimulating the exhalant vessels on the inner surface of the intestines, so as to cause a larger portion of serous fluid to be poured out, which at once dilutes the contents of the canal, and by its operation, aided by the stimulus of the saline matter, accelerates the peristaltic motion. By the watery evacuation which they thus occasion from the general system, they are particularly adapted to those cases where inflammatory action or tendency to it exists. Sulphas magnesije. Sulphate of Magnesia. This salt, formerly known by the name of Bitter Purging Salt, and Epsom Salt, is found in mineral waters, whence it has been extracted, but at present is 278 CATHARTICS. principally obtained from the liquor remaining after the crystallization of muriate of soda from sea-water, which holds a quantity of it, and of muriate of magnesia dis- solved. This is boiled down, and when exposed to suf- ficient cold affords a mass of slender needle-like crys- tals. These are deliquescent from the presence of a little muriate of magnesia; the sulphate, when pure, forms large regular crystals, which are rather efflorescent. They are soluble in nearly an equal weight of water. Their taste is extremely bitter. This salt is used as a purgative, in a dose of from one to two ounces, dissolved in water. Though its taste be bitter, it has been remarked that it remains better on the stomach than many other cathartics, especially when given in small repeated doses, and in a solution largely diluted. Exhibited in this manner, it has been particu- larly recommended in ileus and colica pictonum. Sulphas Sod^e, Sulphate of Soda, long known by the name of Glauber's Salt, is prepared by various pro- cesses on a large scale; but in that given in the Phar- macopoeias, it is obtained from the residuum of the decomposition of muriate of soda, by sulphuric acid, in the preparation of muriatic acid. The saline mass is dis- solved in water; any excess of acid is neutralized by the addition of lime, and the pure sulphate of soda is ob- tained by evaporation. Its crystals are six-sided prisms; they are efflorescent, soluble in three parts of cold, and in an equal part of boiling water. The taste of this salt is very bitter and nauseous. It is one of the saline pur- gatives in most common use. Its medium dose is an ounce and a half, dissolved in six or eight ounces of water. Sulphas potass^e. Sulphate of Potash, formerly named Vitriolated Tartar, is prepared by the direct combination of its principles, or by neutralizing the ex- cess of acid, in the residuum of the distillation of nitric acid from sulphuric acid and nitre. It forms in small irregular crystals, which require 17 parts of cold water CATHARTICS. 279 for their solution. In a dose of 4 or 6 drachms, this salt acts as a purgative, but its comparatively sparing solu- bility prevents it from being much employed; in one of 2 or 3 drachms, it is given as an aperient, frequently in combination with rhubarb or other vegetable cathartics. Super-tartras potassjE. Super-Tartrate of Potash, formerly Crystals or Cream of Tartar, (Crystalli vel Cremor Tartari.) This salt is gradually deposited from wine, in the progress of the slow fermentation which it suffers when kept, and is purified by repeated solutions and crystalli- zations. It consists of potash, with an excess of tartaric acid. Its taste is sour. It is in irregular crystals, which are sparingly soluble in water, requiring about 60 parts of cold, or 30 of boiling water. This salt operates as a purgative in a dose of 4 or 6 drachms, and being free from any unpleasant taste, it is not unfrequently used, given generally under the form of electuary; the only inconvenience attending its operation, is its being liable to occasion flatulence; and if habitually used, it is liable from its acidity to injure the tone of the stomach. It appears, at the same time, to increase the action of the absorbent system; hence as a hydragogue and diuretic it is employed in dropsy, and is also the cathartic most effectual in removing obesity. Tartras potass*. Tartrate of Potash. Tartarum Solubile. So- luble Tartar. This salt, the neutral tartate of potash, formerly nam- ed Soluble Tartar from its greater solubility, is prepar- ed by saturating the excess of acid in the super-tartrate by the addition of potash. From its affinity to water, it is not easily crystallized with regularity; when obtained by evaporation, it is even somewhat deliquescent: its taste is bitter. It is a mild purgative, and at the same time operates effectually, given in a dose of six drachms or an ounce. 280 CATHARTICS. Tartras sodje et potassjE. Tartrate of Soda and Potash. This salt, formerly known by the name of Rochelle Salt, is a triple one, being prepared by saturating the excess of acid in the super-tartrate of potash by soda. It crystallizes in large and regular transparent rhomboi- dal prisms, which are permanent in the air, and soluble in about six parts of cold water. Its taste is less unplea- sant than that of the greater number of the saline purga- tives, and it operates in a similar manner. Its medium dose is an ounce, given usually dissolved in tepid water. Phosphas sodje. Phosphate of Soda. To prepare this salt, bones are calcined to whiteness? so as to obtain the phosphate of lime which is their base. This is submitted to the action of sulphuric acid, which combines with part of the lime, and leaves a super-phosphate of lime, which is dissolved by water. To this solution, a solution of carbonate of soda is added, till there be a slight excess of alkali; the soda combines with the excess of phosphoric acid, and by evaporation the phosphate of soda is crystallized. Its crystals are rhomboidal prisms. Its taste is the least nau- seous of all the saline purgatives, and its operation is equally mild and effectual. Hence it has been establish- ed in practice, and is useful as a cathartic where there is any tendency to nausea. One ounce of it is given, dissolved generally in tepid water, or soup made with- out salt. Besides the preceding Cathartics, there are some which are employed only under the form of Enema. Murias sodje. Muriate of Soda, Common Sea Salt. This salt probably has some cathartic power, but its strongly saline taste prevents it from being employed. It forms the active ingredient, however, of the common CATHARTICS. 281 domestic enema; from half an ounce to an ounce of it being dissolved in a pound of tepid water, and a small quantity of expressed oil added. Terebinthina veneta. Venice Turpentine. Pinus Larix. Moncec. Monadelph. Conifere. The resinous juice of this tree, the Larch, exudes from incisions made in its trunk. It is of the consis- tence of honey, has the peculiar smell of the turpentines, and a bitter acid taste. It consists of resin and essential oil; sometimes it is employed as a cathartic under the form of enema, half an ounce of it being triturated with the yolk of an egg, and suspended in a sufficient quan- tity of water. As it has a considerable share of acrimo- ny, it is employed only where those of milder operation fail. NlCOTIANA TABACUM. TobaCCO. (p. 143.) The smoke of tobacco, introduced into the intestines, has sometimes succeeded in producing evacuation in colic and ileus, after other purgatives have failed, not improbably from its narcotic operation inducing relax- ation of the muscular fibre. An infusion of 1 or 2 drachms of it in a pint of warm water is more conve- nient; but much caution is requisite in the use of either, as tobacco, from its narcotic power, is apt to induce extreme sickness and debility. It is only where other methods have been unsuccessful, that its administration can be proper. Vol. I. 2 N 282 CHAPTER IX. OF EMMENAGOGUES. The medicines distinguished by the appellation of emmenagogues, are those which are capable of pro- moting the menstrual discharge. The suppression of this discharge is supposed to arise from debility of the uterine vessels, or deficiency of action in them. Hence, it might be inferred, that the medicines capable of exciting it must be such as can stimulate these vessels. General stimulants, or tonics, may to a certain de- gree have this effect, since, in consequence of their ac- tion, the uterine vessels must be stimulated in common with other parts. There are accordingly several stimu- lants, both diffusible and permanent, employed as em- menagogues. It is doubtful whether there is farther any particular determination to these vessels. It is sufficiently certain, that there are many substances, which, when received into the stomach, have their stimulant operation more particularly determined to one part than to another; to the kidneys for example, the bladder or other organs. It seems possible, a priorit that there may be substances disposed to act more peculiarly on the uterus; yet expe- rience does not confirm this supposition; there being perhaps no proof of any of the substances styled Era- menagogue, producing their effect from any specific power. A stimulant effect, however, produced in neighbour- ing parts, seems to be in some degree propagated to the uterine vessels; and hence several medicines exert an emmenagogue power, greater than can be ascribed to any general action they exert on the system. It is thus that some substances, belonging to the class of cathar- tics, have been supposed to act, their stimulus being EMMENAGOGUES. 283 communicated from the larger intestines to the uterus. They are probably of advantage too in amenorrhcea, sim- ply as cathartics, removing that state of torpor in the in- testinal canal connected with the disease. There is also one stimulus, that of electricity, which can be brought to act directly on the uterine system, and it has been sometimes found to operate as a powerful emmenagogue. The individuals belonging to this class may be ar- ranged in some measure according to these distinctions; the most active of them being substances belonging to other classes; and there being a few only supposed to be possessed of any specific emmenagogue power. With regard to all of them, it may be added, that there are no medicines so uncertain in their operation, and none in which the conclusions respecting their efficacy are more liable to fallacy. 284 EMMENAGOGUES. FROM THE CLASS OF ANTISPASMODICS. Castoreum. Ferula assafoetida. bubon galbanum. FROM THE CLASS OF TONICS. Feruum. Hydrargyrum. FROM THE CLASS OF CATHARTICS. Aloe. helleborus niger. SlNAPIS ALBA. RUBIA TINCTORUM. RUTA GRAVrOLENS. JUNIPERUS SABINA. Castoreum. Castor. (Page 153.) Under the history of Castor already given, it was remarked, that it appears to be a substance wholly inert. As an emmenagogue, it has been given in the dose of ten grains in substance, or more frequently under the form of tincture in the dose of one drachm. No reliance is now placed on its powers. Assafoetida. Assafoetida. (Page 156.) All the foetid gums have been supposed to possess, along with their antispasmodic property, the power of acting more peculiarly on the uterine system, and have EMMENAGOGUES. 285 been therefore employed as emmenagogues. Assafoetida, the strongest of them, has been given in amenorrhoea m a dose of ten or fifteen grains, or in the form of tinc- ture; but probably with little advantage. Galbanum, another of these foetid gums, next in strength to assa- foetida, has been given in a similar dose. Ferrum. Iron. (Page 174.) The powers of iron as a tonic may be supposed ca- pable of being exerted on the uterine system, and of removing suppression of the discharge arising from deficient action of the uterine vessels, more especially when this is connected with a state of general languor and debility. In such cases, accordingly, it is frequently employed as an emmenagogue. .The carbonate of iron is given ma dose of five or ten grains daily, continued for some time; the more active preparations of the sul- phate and muriate are likewise prescribed, but in gene- ral there is some difficulty in continuing their adminis- tration, unless in small doses, from the irritation they are liable to occasion. The chalybeate mineral waters afford perhaps the best form of administering iron in amenorrhoea. Hydrargyrum. Quicksilver. (Page 164.) The general stimulant operation of this metal mav like that of iron, be supposed to be so far exerted on the uterine system, as to obviate any state of diminished action; some of its preparations are accordingly occa- sionally employed in amenorrhea. The mild muriate or calomel is the preparation generally used. It is jyiven in the dose of a grain; more frequently however, in com- bination with other emmenagogues, to promote their action, than alone. Aloe. Aloes. (Page 274.) This cathartic, it has already been remarked, is sun- posed to operate more peculiarly on the larger intes- tines; and its stimulant operation, it has been imagined 286 EMMENAGOGUES. is thence propagated to the uterus. Hence its celebrity as an emmenagogue, though what efficacy it has pro- bably depends principally, if not entirely, on its mere cathartic power. It is given under the form of pill or tincture; and frequently in combination with other remedies, particularly with myrrh, rhubarb, and the preparations of iron. Helleborus niger. Black Hellebore. (Page 272.) Black Hellebore is a powerful cathartic; it was also highly recommended by Mead as an emmenagogue under the form of tincture, one drachm of this being given as a dose at bed time, and continued for some time. Its emmenagogue might be supposed to depend on its cathartic power; in this dose, however, and under this form, it has little sensible effect; and any advantage derived from it is extremely doubtful. The extract has been employed as a more active preparation in combina- tion with aloes, or with carbonate of iron. Sinapis alba. Mustard. (Page 256.) Semen. Th e seeds of this plant have a considerable degree of pungency, and when taken unbruised to the extent of half an ounce or an ounce, have a purgative effect. This is a popular remedy, not unfrequently used in amenor- rhoea and chlorosis. Rubia tinctorum. Madder. Tetrand. Monogyn. Stellate. Radix. South of Europe. The root of this plant is in slender twigs, of a red colour; it has a bitter taste, with little smell. It has been recommended as an emmenagogue, in a dose of half a drachm thrice a-day. It appears to be nearly inert, and its inefficacy is generally acknowledged. Ruta graveolens. Ruta. Rue. Decand. Monogyn. Multisiliqu*. Herba. South of Europe. This herb, when recent, has a strong unpleasant smell, and a bitter taste. By distillation it affords a EMMENAGOGUES. 287 pungent essential oil. It has been prescribed as an emmenagogue under the form of the watery infusion; and the oil is sometimes combined with aloes, and other medicines of the same class, probably with little advantage. Offic. Prep.—Extr. Rutae Gr. Ed. Dub.—0\. Rutce, Dub.—Confect. Rutae, Lond. Juniperus sabina. Savin. Dioecia. Monadelph. Conifere. Folia. South of Europe. The leaves of this plant have a bitter penetrating taste, a strong unpleasant odour, and a considerable degree of acrimony. They afford a very large quantity of essential oil, possessing the general virtues of the plant. Savin is a stimulant, the operation of which has been supposed to be powerfully directed to the uterine sys- tem; so much so, that, according to the common opi- nion, it is capable of procuring abortion. It has in con- formity to this been considered as an emmenagogue, but it is scarcely ever administered internally. Exter- nally, the powder of the dried leaves is used as an escha- rotic, and mixed with lard as a stimulant to excite suppuration from inflamed surfaces. Offic. Prep.—Extr. Sabina?, Ph. Dub.—CevaX. Sa- bin. Dub. Lond.—0\. Sabina;, Ed. Dub. 288 CHAPTER X. OF DIURETICS. Diuretics are those medicines which increase the urinary discharge;—an effect which is probably pro- duced by different modes of operation. It is obvious, that any substance capable of stimu- lating the secreting vessels of the kidneys, by direct application to them, may increase their action, and thus produce a more copious discharge of urine. It is proba- bly in this way, that many of the saline diuretics act: the principal office of these organs seems to be to separate from the blood the saline matter it contains, and which would otherwise accumulate in the system; when sub- stances of this kind, therefore, do not operate as cathar- tics, but are received into the circulating mass, they are brought to the kidneys in the course of the circulation, are secreted by their vessels, and exciting in them in- creased action, a larger portion of watery fluid is also secreted. Several of these substances, as nitre, or the fixed alkalis, can be detected in the urine by chemical tests after they have been administered, and therefore there can be little doubt of this being the mode in which they operate. There is evidence even of some vegetable diuretics passing off by the same emunctories. The flavour of asparagus, or of garlic, or turpentine, for example, may be observed in the urine discharged an hour or two after they have been received into the stomach. It is also probable, however, that a diuretic effect is in other cases produced by substances acting only on the stomach, the action they excite being communica- ted by sympathy to the kidneys. Squill and tobacco appear to act in this manner, as there is no proof that they are received into the circulating mass; they act DIURETICS. 289 very peculiarly on the stomach, and when they occasion vomiting or purging, they generally fail in their diure- tic effect. It may be concluded, therefore, that they ex- ert a peculiar action on the stomach, which, propagated to the kidneys, by means of the general connection subsisting between all the parts of the system, causes an increase in the urinary discharge. The different kinds of ardent spirits diluted with water, seem to act in a similar manner, as their diuretic effect usually takes place very speedily. There is still a third mode, in which it seems proba- ble that some substances produce a diuretic effect, es- pecially in a state of disease. It is known that persons who drink sparingly, discharge less urine than others; or that where the watery part of the blood is carried off by perspiration, the urinary discharge is diminished. It is farther known, that large draughts of water, or of any mild diluent, if not determined to the skin by external warmth, occasion an increased discharge of urine. It seems probable, therefore, that a similar effect may be produced, by the action of substances which power- fully stimulate the absorbent system, and thus bring an increased quantity of serous fluid into the course of the circulation. Digitalis is probably a remedy of this kind. Its effect as a diuretic is more certain and powerful, when given to a person labouring under dropsy, than to one in health; it appears too to be one of those me- dicines which stimulate most powerfully the absorbent system; its diuretic power in dropsy, therefore, is pro- bably principally owing to its enabling the absorbents to take up the serous fluid effused; this is of course brought into the circulation, and like any other watery fluid is discharged by the kidneys. On the same principle is explained the utility of a practice, which has been employed to promote the ac- tion of diuretics, that of conjoining mercury with them. Thus, the action of squill as a diuretic, is rendered more certain and powerful by combination with calo- mel; each of them being given in separate doses, or Vol. I. 2 0 290 DIURETICS. both being united in one formula. The efficacy of this is probably dc ivcd from the mercury stimulating the absorbents, and, by introducing the effused fluid into the system, promoting the direct diuretic action of the squill. The action of diuretics is promoted, by drinking mod«rately of watery liquors; hence the practice that was formerly adopted in dropsy, of diminishing the al- lowance of drink, is explodtd; it was of little benefit in preventing the accumulation of effused fluid, and the abstinence from liquids that was enjoined, rather pre- vented the action of the diuretic remedies that were employed for the cure of the disease. Many cases even have occurred, in which pure water, mineral waters, or mild diluents, have acted as diuretics, and effected a cure in dropsy. The action of diuretics is also considerably depend- ent on the state of the vessels of the skin. If, when a medicine of this class has been given, these vessels are stimulated by external warmth, its action is rather de- termined to the surface, and sweat or diaphoresis takes place. But if the surface is kept cool, the diuretic effect is more certain; so much indeed does this state of the surface determine to the kidneys, that the usual dia- phoretics may be brought to act as diuretics. The general effects of diuretics are sufficiently evi- dent. They discharge the watery part of the blood, and by that discharge they indirectly promote absorption. Dropsy is the disease in which they are principally em- ployed, and they are adapted to every form of it. The disease can also be removed with less injury to the pa- tient, by exciting the urinary discharge, than by any other method. The success of diuretics in dropsy is however very precarious; sometimes none of them suc- ceed; sometimes one acts more powerfully than another, though in this there is no uniformity; nor are the causes of this variety of operation well understood. In general, it is obvious, that where a strong predisposition to the disease exists, or where it originates from organic affec- DIURETICS. 291 tions of the liver, or other chylopoetic viscera, no great advantage can be expected from the mere evacuation of the water by the action of diuretics: it is only in those cases where an accumulation of fluid has taken place from diminished absorption, or some similar cause, that they can be expected to effect a cure. It accordingly often happens in practice, that an increased discharge of urine is effected by the exhibition of diu- retics, and still the dropsical swellings are not removed, or, if they are, they speedily return. Diuretics have been likewise used in calculous affec- tions, with the view of preventing at least the increase of the calculus, by rendering the urine more watery: and they have occasionally, though rarely, been em- ployed to lessen plethora, or check profuse perspira- tion. The use of diluents, so as to increase the quan- tity of urine, is of use in gonorrhoea, and other affec- tions of the urinary passages, by lessening the acrimo- ny of the urine, which excites pain from its action on these parts, when they are in an inflamed state. The cautions with regard to the administration of diuretics, are obvious from what has been said of their operation. The surface of the body must be kept cool, and therefore the doses of the medicine ought to be given in the course of the day, and the patient should if possible be kept out of bed. The use of diluents ought to be permitted, at least this is more necessary with respect to those diuretics belonging to the class of salts, and which operate directly on the secreting ves- sels of the kidneys. The individual diuretics may be considered under the subdivisions of Salts, Vegetable Diuretics, and one or two derived from the animal kingdom. 292 DIURETICS. SALINE DIURETICS. POTASSA. Acetas potass.*:. Super-tartras potassje. NlTRAS POTASSJE. Spiritus ETHERIS NITROSI. FROM THE VEGETABLE KINGDOM. SciLLA MARITIMA. Digitalis purpurea. NlCOTIANA TABACUM. SOLANUM DULCAMARA. LACTUC \ VIROSA. COLCHICUM AUTUMNALE. GKATIOLA OFFICINALIS. Spartium SCOPABIUM. JUNIPERUS COMMUNIS. COPAIFERA OFFICINALIS. PlNUS BALSAMEA. PlNUS LAKIX. FROM THE ANIMAL KINGDOM. Meloe VESICATORIUS. SALINE DIURETICS. Potassa. Potash, either pure, or in the state of sub- carbonate, is a diuretic; and, as has been already re- marked, is secreted by the kidneys, so that when con- tinued for a sufficient time, it renders the urine alka- line. The saline matter from the ashes of broom, worm- wood and other plants, which is sub-carbonate of pot- ash, more or less pure, used formerly to be frequently prescribed in dropsy. It is difficult to continue the ad- ministration of the alkali, however, to the requisite ex- tent, without occasioning irritation; and being inferior in diuretic power to the super-tartrate of potash, it has fallen into disuse. When employed, the dose of the sub- carbonate is 20 or SO grains dissolved in a large quan- DIURETICS. 293 tity of water, and repeated three or four times in the course of the day. Acetas potassje. Acetate of Potash. Sal Diureticus. This salt, prepared by saturating potash writh acetic acid, and evaporating the solution to dryness, is obtain- ed in the state of a white foliated mass, deliquescent and very soluble in water. It has been considered as a powerful diuretic, and has been used in dropsy, half a drachm of it dissolved in water being given every hour or two until it operate. It is uncertain in its operation, however, and has therefore fallen into disuse. Super-tartras potassje;. Super-tartrate of Potash. Cream of Tartar. (Page 279.) This salt, of which the chemical history has been already given, and its applications as a cathartic noticed, is extensively employed as a remedy in dropsy, and is inferior to few of the substances belonging to this class. There are two modes under which it is exhibited, either so as to obtain principally its diuretic effect, or along with this its action as a hydragogue cathartic. When given with the first intention, the form of exhibition is solution in water, from half an ounce to an ounce being dissolved in the due proportion of water, and this being taken in the course of the day, its operation on the kid- neys being promoted by dilution. The more usual prac- tice, however, is to give it in substance, either diffused in a little water, or made into an electuary with syrup, and in such doses as to occasion purging to a certain extent. The dose is various, its operation being appa- rently much dependent on the action of the absorbents being excited, and this, in different states of disease, being effected with more or less difficulty. Half an ounce is given at first, and this is increased to an ounce, or even two ounces in twenty-four hours, the increase of dose being continued until its effects on the kidneys or bowels is obtained, and care being taken not to push it so far as to produce greater evacuation than the strength of the patient can support. It generally causes 294 DIURETICS. a considerable discharge of serous fluid into the intes- tinal canal, so as to produce watery evacuations, and at the same time augments the quantity of urine; the size of the dropsical swelling soon begins to be reduced; and the effused water, according to those practitioners who have represented its efficacy in the most favoura- ble light, is not only removed, but any renewal of the -effusion is prevented with more certainty than by the action of other diuretics: hence it has been regarded as in general superior to the other medicines of this class in the treatment of dropsy. There can be no doubt that super-tartrate of potash proves often a powerful remedy; yet the general remark applies to this as well as to the other diuretics, that it sometimes fails, where others succeed. It is frequently necessary too to give it in such large doses to obtain its diuretic or hydragogue effect, that it excites nausea and flatulence, weakens the appetite, and injures the tone of the stomach: and as a greater degree of debility is in- duced by the operation of purging than by merely ex- citing the urinary discharge, there is some risk of the powers of the system being exhausted under its pro- tracted use. These effects, therefore, require to be guarded against, and sometimes render it necessary to substitute other diuretics where it has received a fair trial. Nitras potass.*. Nitrate of Potash. Nitrum. Nitre. This salt, consisting of nitric acid and potash, is frequently formed on the surface of the soil, in warm climates. In the South of Europe, its production is accelerated by artificial arrangements. Animal and vege- table substances, in a state of decomposition, are mixed with a quantity of carbonate of lime, the mass is ex- posed to the air, but protected from the rain, and is occasionally stirred up. After a number of months, the materials are found to contain nitrate of lime and nitrate of potash. These salts are extracted by lixiviation with water: impure sub-carbonate of potash is added, by DIURETICS. 295 which the nitrate of lime is decomposed, and the quan- tity of nitrate of potash increased; and this salt is puri- fied by repeated solutions and crystallizations. During the process by which the nitrate of potash is formed, it appears that the oxygen of the atmospheric air, and that afforded by the vegetable matter, combines with the nitrogen of the animal matter so as to form nitric acid, which is attracted in part by the lime present, and in part b)r a quantity of potash, either contained in the ma- terials, or, as some have supposed, actually' formed dur- ing the process. Nitrate of potash is crystallized in bexaedral prisms. Its crystals are soluble in six parts of cold, and in an equal weight of boiling water. It is decomposed by heat, affording a large quantity of oxygen gas; and from the facility of this decomposition, is an important phar- maceutic agent in oxidating bodies. This salt has a cool and sharp taste, and occasions a sense of coldness in the stomach when swallowed. When given in moderate doses, continued for some time, its presence can at length be detected in the urine by che- mical tests. Its virtues are those of a refrigerant and diuretic; and, as possessing both, it has been used prin- cipally to relieve ardor urinae in gonorrhoea. The prac- tice, however, is now relinquished, either as inefficaci- ous, or as rather hurtful, if the nitre is secreted with the urine, as it must render it more stimulating. Its dose is from 5 to 20 grains repeated twice or thrice a-day, with the free use of diluents or demulcents. Its diure- tic power is too inconsiderable to admit of its being employed as a remedy in dropsy. Offic. Prep.—Troth. Nitrat. Pot. Ed. Spiritus etheris nitrosi. Spirit of Nitrous Ether. Nitric acid, added in due proportion to alkohol, converts it into a species of ether; but as the process is difficult, from the violent chemical action that taker place, it has long been the practice to use less acid than is required to change the whole alkohol into this pro- duct; a portion of nitric ether is formed, and this is 296 DIURETICS. obtained by distillation, combined with the unchanged alkohol, and generally also from the mutual action not having been complete with a portion of free acid. This forms what used to be named Spiritus Nitri Dulcis, what is now named Spiritus Etheris Nitrosi. Its odour is fragrant; its taste sharp and acidulous. In medicine it is employed as a refrigerant and diuretic, in a dose of 20 or 30 drops. Being grateful to the stomach, and re- lieving flatulence, it is often used to correct or promote the action of more powerful diuretics in dropsy. DIURETICS FROM THE VEGETABLE KINGDOM. Scilla maritima. Squill. (Page 255.) The medicinal applications of squill as an emetic have been already stated. .Under this article are to be considered its powers as a diuretic. Squill, foxglove, and super-tartrate of potash, are the diuretics principally employed in modern practice in the treatment of dropsy; and it is not easy to assign precise- ly their comparative powers, one frequently proving successful when either of the others has previously fail- ed. Squill operates more directly as a diuretic than the super-tartrate of potash does, and is not liable, even if its administration has been carried rather far, to produce those injurious effects which arise from the action of foxglove in an over dose. As a diuretic, squill is always given in substance, un- der the form of the dried root. Its dose is from one to three grains. A grain may be given at first, morning and evening, in the form of pill, and this increased slowly until its diuretic effect is obtained. If the dose is too large, it is liable to excite nausea, and the rule has even been delivered, to give it always to the extent ne- cessary to induce some degree of nausea. The produc- tion of this effect can be regarded, however, only as a test of the squill being in an active state; it is not neces- sary to its diuretic operation; it proves distressing to the patient; and it has been observed, that when it has DIURETICS. 297 once been given to such an extent as to induce this state of the stomach, the same state is more liable to recur even when after an interval it is given in smaller doses. Its nauseating operation, therefore, ought rather to be avoided by the due regulation of the dose. The diuretic power of squill is much promoted by combination with mercury, and it is more frequently perhaps employed in this combination than alone. Of the mercurial preparations, either the common pill, or calomel, may be used; the usual medium dose from which we obtain the general action of either on the sys- tem, being added to the dose of the squill, or being given in the evening, while the squill is given in the morning. The superiority of their combined action probably de- pends on the mercury stimulating the absorbent sys- tem, while the squill excites the action of the vessels of the kidneys. This combination is farther well adapted to the treatment of dropsy, connected as it frequently is with obstruction or chronic inflammation of the liver or neighbouring organs. Where the mercurial preparation occasions purging, as this impedes the diuretic action of the squill, mercurial friction may be substituted. Digitalis purpurea. Foxglove. (Page 138.) Foxglove has already been considered as a narcotic; it is a still more important article of the Materia Medi- ca as a diuretic. It had frequently been used as an em- pirical remedy in dropsy; but the occasional violence of its narcotic operation, when not administered with due precaution, prevented it from being employed in prac- tice, until Dr. Withering pointed out, with more preci- sion, the rules to be attended to in its exhibition. It is difficult, as has been already remarked, to com- pare the powers of the principal diuretics; yet, on the whole, perhaps foxglove is superior to all of them in eva- cuating the water in dropsy: and the conclusions of Withering are still nearly just, that " so far as the re- " movalof the water will contribute to cure the patient, " so far may be expected from this medicine;" and that Vol. I. 2 P 298 DIURETICS. " although digitalis does not act universally as a diuretic, " it does so more generally than any other."—In hydro- thorax, its superiority to other diuretics is more clearly established than in ascites or anasarca; and in the first of these states of dropsy, it is unquestionably superior to any other remedy. Withering remarked, that it was most successful in those cases of dropsy in which debility was completely marked, where the countenance is pale, the pulse weak, and the muscular energy reduced; while, in an opposite state of the system, it was more liable to fail. In the latter case, therefore, he recommended a pre- vious exhibition of squill, or of super-tartrate of potash, by which some reduction of strength might be induced. The observation, however, has not altogether been con- firmed by subsequent experience. If it were, it would afford a strong presumptive proof, that the efficacy of foxglove in dropsy depends on its stimulant action. There is a peculiarity in its operation, that it may be continued for some time without sensibly increasing the flow of urine; the increase then suddenly commences, and continues of itself without requiring the continued administration of the remedy for several days, and to a very great extent, so that the dropsical effusion is more speedily reduced by the action of it than by any other diuretic. Its diuretic power too appears only when it is administered in dropsy, and hence there can be little doubt that it operates principally, if not entirely, by ex- citing the action of the absorbents. The absorbed fluid is then discharged by the kidneys. The diuretic effect is not connected with its nauseating operation, or with the reduction in the force of the circulation; it can, on the contrary, be obtained without either of these accompany- ing it; and Withering remarked even, that he had found the increased discharge of urine to be checked, when the doses had been imprudently urged so as to occasion sickness. He observed also, that if it purges, it is almost certain to fail. Foxglove is given under the form of the dried leaves in substance, or in infusion or tincture. The tincture has been supposed to be better adapted to its exhibition as DIURETICS. 299 a narcotic. The infusion is a preparation sufficiently uniform and active, and its dose is rather more easily regulated with precision, so as to admit of a gradual in- crease, than that of the powder. Its action too is at once exerted on the stomach, and there is therefore less risk of its effect being delayed until it is accumulated. The medium dose of the powder is at first from half a grain to a grain twice a-day: from half an ounce to an ounce of the infusion, prepared according to the formula of Withering, now received into the Pharmacopoeias, is a similar medium dose. The great desideratum with regard to this remedy, is to conduct its administration so as to obtain its full diu- retic effect, without those consequences which arise from it when its action is accumulated in the system. The rules given by Withering for its administration, are to give it in a dose from 1 to 3 grains of the powder twice a-day; or one ounce of the infusion, which, if the symp- toms be urgent, or the patient stronger than usual, may be given once in eight hours: and the dose is to be con- tinued until the medicine either acts on the kidneys, the stomach, the pulse, or the bowels; and is to be stopped on the first appearance of any one of these effects. Though Withering enjoined strictly the caution ne- cessary in the use of this remedy, the doses prescribed in his directions are perhaps rather large; and the method which has sometimes too been recommended of pro- gressively increasing the dose until the effects are obtain- ed, is improper. If the dose be at first small, or at least if having been raised to one grain of the powder, or one ounce of the infusion, twice in twenty -four hours, it be continued at this quantity, the diuretic operation will be obtained in no long time without any unpleasant symp- tom, and when it commences, will continue of itself, even though the dose be suspended. Or if, from pecu- liarity of habit, or state of disease, the dose requires to be increased, it ought to be done slowly, and without that regularly progressive augmentation which has been recommended. And if the effect begin to cease before the reduction of the dropsical swelling be completed, it 300 DIURETICS. may be easily renewed by a repetition of this moderate dose. This mode of administering foxglove is that sug- gested by the nature of its action. The peculiarity which has always been pointed out as characteristic of this me- dicine, is its tendency to accumulate in the system, its effects not appearing for a time, but at length being sud- denly induced. There is no necessity, therefore, to in- crease its dose, or to give one that is large, with the view of speedily inducing its action, since, merely from its continued administration, this will in no long time be established, and without that hazard which is otherwise incurred from this peculiarity in its operation. The alarming symptoms which foxglove is liable to produce, it has already been remarked, are best obviated by small doses of spiritous cordials warm; sulphuric ether, aro- matic spirit of ammonia, bitter infusions, and aromatics. Vinegar, which is an antidote to other narcotics, might be tried. There are other diseases in which foxglove has been supposed to prove useful by its diuretic power; as in insania, or in epilepsy connected with serous effusion in the brain; and more especially in dyspnoea arising from serous effusion in the bronchia?,—anasarca pulmonum, as this affection is named. It may, in the treatment of dropsy, be advantageously- combined with other diuretics; and its action, like that of squill, is said to be promoted by the operation of mer- cury. Nicotiana tabacum. Tobacco. (See p. 143.) Tobacco, in its general action, has some resemblance to foxglove, being narcotic, emetic, and diuretic. As a diuretic, it has been employed in dropsy, under the form of infusion, one ounce of the dried leaves being infused in a pint of water, and six or ten drops being given, and gradually increased to 60 or even 100. It possesses, however, no peculiar advantage to recommend it, and its diuretic effect is generally accompanied with sickness and vertigo. DIURETICS. 301 Solanum dulcamara. Woody Nightshade. Bitter-Sweet. Pen- tand. Monogyn. Solanacee. Stipites. Indigenous. The young shoots or branches are the part of this plant used in medicine; when first chewed, they have a bitter taste, which is soon followed by a degree of sweetishness, a peculiarity whence its name is derived; their smell is strong and disagreeable. By drying, their activity is much impaired. An infusion or decoction of the dried stalks in water has been recommended as a diuretic in dropsy, but it is a remedy of uncertain ope- ration, and is scarcely ever prescribed. Offic. Prep.—Decoct. Dulcamar. Ph. Lond. Lactuca virosa. Strong-scented Lettuce. (P. 145.) This plant, though it possesses a narcotic quality, is also a diuretic, and has been recommended under the form of the inspissated juice as a remedy in dropsy, the dose being gradually increased from 5 or 10 grains to 2 or 3 drachms. Though celebrated by the German practi- tioners, it is never used in this country. Colchicum autumnale. Meadow Saffron. Colchicum. Hexand. Trigyn. Liliacee. Radix. Indigenous. The root of this plant is bulbous; when recent, it is extremely acrid, a small quantity occasioning a sense of burning heat in the stomach, strangury and tenesmus; at other times, it is entirely void of acrimony; differences owing to climate, age or season. It was recommended by Storck as a remedy in dropsy, under the form of oxymel or syrup; these have been received into the Pharmacopoeias, the dose of either being 2 or 3 drachms. From the uncertainty, however, of its operation, colchi- cum has not been established in practice. Offic. Prep.—Syr. Colch. A. Ed.—Oxymel. Colch. Dub.—Acet. Colch. Lond. Gratiola officinalis. Hedge-Hyssop. Diand. Monogyn. Perso- nate. Herba. South of Europe. The leaves of this plant have a strong bitter taste, with little smell. They prove emetic and cathartic, but in a smaller dose produce a diuretic effect, and have been 3Q2 DIURETICS. recommended under the form of infusion in the treat- ment of dropsy. Their operation, however, is always uncertain, and liable to be violent. Spartium scoparium. Broom. Diadelph. Decand. Papilionacee. Summitates. Indigenous. The tops of the young branches of the broom have a bitter taste, which is communicated both to water and alkohol. The watery decoction is used as a popular remedy in dropsy, and sometimes with success. It acts in general both as a cathartic and diuretic. Offic. Prep.—Extr. Genist. Ph. Dub. Juniperus communis. Juniper. Diacia. Monadelph. Conifers. Bacce. Indigenous. The berries of this shrub have an aromatic smell, and a warm sweetish taste, with a degree of bitterness, the former qualities residing in the pulp, the last in the seeds Distilled with water they afford a considerable quantity of essential oil. Juniper berries given in infusion prove diuretic. The essential oil retains this property; and the spirit of juni- per, or diluted alkohol impregnated with it, has been prescribed as a cordial and diuretic in dropsy. Offic. Prep.—Ol. Juniper. Spir. Junip. C. Comp. Ed. Lond. Dub. Copaifera officinalis. Balsamum Copaibae. Balsam of Copaiba or Copavia. Decand. Monogyn. Dumose. Balsamum. South America. This resinous juice, for it is improperly named a bal- sam, is the produce by exudation from incisions made in the trunk of the tree. It is thick and tenacious, trans- parent, with a yellow tinge; has a peculiar smell not dis- agreeable, and a pungent bitter taste. It is soluble in alkohol, and in expressed and essential oils. Distilled with water, it affords nearly half its weight of an essential oil, an insipid resin being the residuum. Balsam of Copaiba increases the urinary discharge, and communicates to the urine a violet odour. In too large a dose it is liable to excite inflammation of the urinary passages. From its power of stimulating these DIURETICS. 303 parts, it frequently proves successful in the cure of gleet, where the inflammation has entirely subsided, and the discharge continues from weakness of the exhalants or absorbents. It has also been given inleucorrhcea, and in haemorrhoidal affections. Its dose is 20 or 30 drops twice or thrice a-day, given in the form of bolus, or, what is pre- ferable, as remaining more easily on the stomach, and less irritating, diffused in water by the medium of mucilage.* Pinus balsamea. Balsamum Canadense. Canadian Balsam. Mo- ncecia. Monadelph. Conifere. Balsamum. North America. This resinous juice, for it, like the preceding, is improperly named a balsam, as it affords no benzoic acid, exudes spontaneously from the trunk of the tree. It is of a light yellow colour, transparent, tenacious, and inflammable. By age it becomes thicker; its smell is agreeable; its taste pungent. It is soluble in alkohol and oils, and affords an essential oil by distillation, similar to the oil obtained from the other turpentines or resinous juices of the different species of pinus. The medicinal virtues of this resinous juice seem to be the same as those copaiba, and it is used for the same purposes. Its dose is from 30 to 50 drops. Of any ©f the turpentines it is the purest. * It is now upwards of ten years since I have trusted exclusively to the Balsam Copavia in the cure of gonorrhoea, and my confidence in its powers is fully established. Contrasted with the ordinary mode of treating the disease by injections, this plan has a decided superio- rity. It is more convenient to the patient. It produces no swelled testi- cle. It occasions no strictures. It leaves no gleet. It is more prompt and certain in the cure. This is no new practice. The Copavia was once much employed in gonorrhoea, but limited chiefly to the advanced stages of the dis- ease and the doses were small. My experience has taught me to pursue an entirely opposite course. I prescribe the medicine at the very commencement of the attack, utterly regardless of all the ap- pearances of inflammation, and exhibit it freely. Nothing more speedily abates the ardor urinae, chordee and other troublesome affections. It will sometimes be useful to combine with the Copavia the dulcified spirit of nitre, and a considerable portion of laudanum. If judiciously administered, the Copavia will commonly effect a cure in three or four days, and sometimes, in a much shorter period. I have 304 ■DIURETICS. Pinus larix. Terebinthina Veneta. Venice Turpentine. Mo?ioecia. Monadelph. Conifere. This juice exudes spontaneously, and in still greater abundance from incisions in the trunk of the tree. It is thick and tenacious, semi-pellucid, of a yellowish colour, has a peculiar smell, and a bitter pungent taste. By dis- tillation, with the addition of a small quantity of water, to prevent the temperature from rising too high, it af- fords a large quantity of an essential oil, which is light, volatile, and inflammable, but more sparingly soluble in alkohol than any other essential oil. The residuum is a resin nearly insipid. Venice turpentine derives all its virtues from its essen- tial oil, and it is this oil, Oleum Terebinthinae, Oil of Turpentine, that is used in medicine, more frequently than the juice itself. It is a powerful stimulant, directed more particularly in its action to the urinary passages, as is evident from the violet odour it communicates to the urine, and. from the inflammation it excites when given in too large a dose. From this specific action it has been employed in gleet in a dose from 5 to 10 drops, but its operation is always liable to be violent. It was highly recommended by Cheyne as a remedy in chronic rheumatism, especially lumbago, given to the extent of 2 or 3 drachms mixed with honey. It is scarcely possi- ble, however, to give it in such a dose without being rejected from the stomach, or acting violently on the urinary organs. Externally it is applied by friction as a stimulant to parts affected with cramp and rheumatism; sometimes too it is used as an application to burns, or as a styptic to bleeding wounds. Resina Alba vel Flava. White or yellow resin is the I have known it often to put an end to the disease in less than twenty-four hours. But to attain this free and prompt operation of the medicine, the patient must honestly abstain f.-om every stimu- lating article of diet or drink, and impose upon himself a complete state of rest. Without these precautions, this and all other modes of managing gonorrhoea are counteracted and abused. I have also found the Copavia very serviceable in relieving the strangury from blisters.—Ed. DIURETICS. 305 residuum of the distillation of turpentine; its various shades of colour arising from the purity of the juice, or from the degree of heat applied. It has little smell or taste, but appears from the practice of the farriers, who give it to horses, to have some degree of diuretic power. It is only employed in the composition of ointments and plasters, which it renders more adhesive, and per- haps more stimulating. Various compositions of this kind have a place in the Pharmacopoeias, as the Ceratum Resinae, or Unguentum Resinosum, long known by the name of Basilicon, the Emplastrum Resinosum and others. Pistacia terebinthinus. Chio or Cyprus Turpentine.—Pinus picea. Strasburgh Turpentine.—Pinus sylvestris. Common Turpentine. Ditec. Pentand. The Chio turpentine is more fragrant and grateful than the preceding; its powers are the same, and not being easily procured, it is never used. The same ob- servation may be made with respect to the Strasburgh Turpentine, the produce of the Pinus Picea. The Com- mon Turpentine (Terebinthinus Communis), the pro- duce of the Pinus Sylvestris, contains less essential oil, and is more offensive to the stomach than any of the other turpentines. DIURETICS FROM THE ANIMAL KINGDOM. Meloe vesicatorius. Cantharis. Spanish Fly. Lytta Vesicatoria. Blistering Fly. Coleoptera. This insect is collected from the leaves of certain plants in Spain and Italy, to which it adheres; they are first exposed to the vapours of vinegar, and are then dried in the sun. They are of a rich, lively green and yellow colour; have a faint unpleasant smell, and a taste slightly acrid. The active matter of cantharides inflames and excoriates the skin, and is used as the basis of the common vesicatories. It appears to have a peculiar de- Voi.I. 2Q 306 DIURETICS. termination to the urinary organs, as even from the ex- ternal application strangury is sometimes induced; and a small dose of the cantharides internally administered acts with much violence on the kidneys and bladder, producing inflammation and a discharge of bloody urine. In dropsy, it has been given as a diuretic in a dose of one grain once or twice a day, continued for some time: it has been prescribed in a similar dose in obstinate gleet and leucorrhoea, and in retention of urine arising from debility of the body of the bladder, or in the oppo- site affection of incontinence of urine. It is principally in the latter of these affections that the internal admi- nistration of cantharides is attempted,—where the ina- bility to retain the urine arises from weakness of the sphincter vesicae, a state which the cantharides by its local stimulant action is adapted to remove. Its action requires to be moderated by the ^ree use of diluents. It has also been employed as a stimulant in amenorrhoea; and it is still more extensively used externally as an epispastic. Offic. Prep.—Emp. Mel. Ves. T. Mel. Ves. Ung. Pulv. Mel. V. Ph. Ed. Lond. Dub.—Emp. Mel. Vesic. Comp. Ung. Inf. Mel. V. Ed.—Emp. Calefac. Dub. CHAPTER XL OF DIAPHORETICS. Diaphoretics are those medicines which increase the natural exhalation by the skin. When they excite this so copiously as to produce sweat, they are named Sudorifics. The operation of both is the same, differing only in degree; diaphoretics in doses sufficiently large acting as sudorifics, and sudorifics in diminished doses, or under peculiar circumstances, occasioning only a slight diaphoresis. The fk:id effused too is in both cases alike, being chiefly the watery part of the blood, with a DIAPHORETICS. 307 slight impregnation of saline matter. In the one case it is discharged more slowly, and therefore passes off in the state of vapour; in the other it is discharged co- piously from the exhalant vessels in the liquid form. The operation of these medicines is not obscure; the natural exhalation is merely increased; the action of the exhalant vessels on the surface must therefore have been augmented, and the substances belonging to this class must be those which stimulate these vessels. Of stimuli of this kind, external heat affords an ex- ample; it is directly applied to the vessels, and must occasion in them an increased action; hence it often produces sweat, and always promotes the action of sudorifics. The same effect may be likewise produced by a dif- ferent operation,—by increasing the general force of the circulation; this acts as a stimulus on the exhalant ves- sels, and increases their discharge. Hence violent mus- cular exercise is perhaps always attended with copious sweating. In one or other of these modes, the medicines belong- ing to this class operate,—either by directly stimulating the cutaneous exhalant vessels, or by indirectly com- municating to them an increased action by increasing the force of the circulation. The saline diaphoretics seem to act in the former manner; they have little or no action on the vascular system, neither increasing the velocity nor force of the circulation; their action therefore is exerted on the sto- mach, and thence communicated to the vessels of the skin. Perhaps they may likewise be absorbed into the mass of blood, as they readily pass with the chyle, or enter the absorbent vessels, and may act more directly on the cutaneous vessels. Those diaphoretics, on the contrary, which are more stimulating, probably act by increasing the force of the vascular system, as they usually augment the force and frequency of the pulse, previous to occasioning sweat. Diaphoresis is not, however, the necessary conse- quence of the circulation being increased in force; for 308 DIAPHORETICS. it often happens that the pulse is frequent and hard, when the skin remains dry. In this case there seems to exist a constriction of the exhalants, sufficient to resist the impetus of the blood, and whatever can remove this will favour sweating. Diaphoresis, therefore, it may in general be said, will follow from increased vascular ac- tion, when the exhalants of the skin are not morbidly con^ricted; and it will take place still more copiously when the circulation is increased in the larger vessels, while the exhalants themselves are relaxed. On this view is to be explained the operation of tepid diluents, and of external warmth in promoting sweat, the ten- dency of both being to increase the force of the circu- lation, and at the same time occasion relaxation of the cutaneous vessels. From the latter effect, small doses of emetics are favourable to diaphoresis; and, from the same principle, the superior sudorific power of the com- bination of opium with ipecacuan, or the preparations of antimony, may perhaps be accounted for; the pri- mary operation of the one being to increase the action of the vascular system; that of the other, by its nau- seating effect, to diminish the action at the surface, as is apparent from the paleness of the skin and the sense of coldness with which nausea is attended. The primary effects of diaphoretics are to evacuate the watery part of the blood, and thus lessen the quan- tity of it in the circulating system; to determine the blood to the surface from the internal parts; to increase the action of the absorbents, and to remove spasmodic stricture of the cutaneous vessels, and render the skin moist and relaxed. It is doubtful, however, whether the first of these ef- fects takes place to any extent; for, during sweating, th'-re is generally considerable thirst: as much fluid may therefore be taken in, as will supply what is thrown out; and farther, the other fluid secretions, particularly that of urine, are diminished during this operation. It is probable, therefore, that li.tle alteration takes place in the quantity of fluid contained in the body from the DIAPHORETICS. 309 action of diaphoretics; and we can scarcely, in any case, ascribe any beneficial effects they produce to this cause. The last effect is perhaps the most important; at least it is on this principle, the removing spasmodic stricture of the cutaneous vessels, that the efficacy of diaphore- tics in inflammatory diseases has been explained. In such affections the skin is dry, and the external heat augmented; but when diaphoresis has been induced, that state is removed, and the skin remains moist and cool. It is with the view of producing these effects that diaphoretics are used in synocha, acute rheumatism, and in the various phlegmasiae. Several circumstances contributed to lead physicians to the free use of diaphoretics in fevers. The skin is generally dry and hot; and it was often observed, that a spontaneous salutary crisis was marked by diaphoresis, or even by a copious sweat. Hence it was concluded, that by following the path nature pointed out, and in- ducing this relaxed state of the vessels of the skin, the disease might be removed. Theory too had its influ- ence in carrying this practice to an immoderate extent, fever being supposed to arise from the presence of morbific matter in the system, and sweating being an evacuation by which it was supposed to be discharged. The limits to the practice have long been established; little advantage appears to be derived from it in the treatment of fevers of the typhoid type, and it is prin- cipally in the various phlegmasiae that it is employed. As evacuating the serous part of the blood, and as promoting absorption, sudorifics have been sometimes employed in the different species of dropsy, especially in anasarca, in which the circulation in the extreme vessels on the surface is more or less languid. Cases occur where it is not easy to increase the discharge by urine, and in these sweating has been had recourse to as less debilitating than purging, the only other evacua- tion that can be excited with advantage. It has been remarked too, that the operation of diaphoretics, when 310 DIAPHORETICS. it has been excited, has been accompanied by an in- crease in the quantity of urine, a proof of absorption having been promoted. It is difficult, however, to ex- cite sweating in dropsy, and the practice is rarely at- tempted. By determining to the surface, and preserving a gen- tle diaphoresis, they are found serviceable in asthma, dyspepsia, habitual diarrhoea, chronic dysentery, and chronic rheumatism. In various obstinate cutaneous affections, as herpes and lepra, advantage has been derived from the use of diaphoretics, probably from altering the morbid state of the extreme vessels on the surface. The use of the warm bath, and the antimonial and mercurial diapho- retics, are found more particularly serviceable in such affections. Several circumstances require to be attended to in the administration of sudorifics. If the disease is in- flammatory, the action of the vascular system strong, and the skin dry, with great heat on the surface, those which are of the stimulating kind arc to be avoided, as if they fail in producing sweat, they may aggravate the symptoms. The free use of warm diluents is proper and even necessary, under the operation of full sweat- ing. The patient should be laid in flannel, not only as preserving the temperature more uniform, but also as it absorbs the moisture which would otherwise carry off the heat too rapidly, and cool the surface. The covering ought rather to be light, as there is no neces- sity for much external warmth. Too much heat, espe- cially when unaccompanied by humidity, sometimes rather prevents sweating, probably by stimulating the exhalant vessels, and increasing their force of resistance. It is promoted by partial fomentation, as the applica- tion of flannel dipped in warm water, and pressed out, to the feet. Lastly, care is to be taken to avoid the ap- plication of cold, either by the admission of cold air to the surface, or the drinking of cold water while the sweat continues, or for some time after it has ceased. When the sweat is to be checked, it is best done by DIAPHORETICS.' 311 drying the surface, removing the patient into dry flan- nel, and allowing him to expose his hands and arms to the air. The particular diaphoretics may be arranged accord- ing to the affinity in their operation, as they operate by increasing the action of the vascular system, or as they act without any sensible stimulant operation, though it is somewhat difficult to trace the distinctions of these, or even with regard to every individual to assign the kind of action it exerts. DIAPHORETICS. Acetas ammonia. CllRAS AMMONIA. Carbonas ammonia. murias ammonia. Sub-murias hydrargyri. antim nium. Sulphur, Opium. Camphor. guaiacum officinale. Daphne mezereum. Laurus sassafras. Salvia officinalis. Acetas ammonia. Acetate of Ammonia. All the ammoniacal salts are supposed to have a diaphoretic power. The acetate is the one which has been principally used; its solution (Aqua Acetatis Am- monias) having been long celebrated under the name of Spirit of Mindererus (Spiritus Mindereri) as a diapho- retic in febrile affections. It is prepared by neutralizing 312 DIAPHORETICS. distilled vinegar, by adding to it carbonate of ammonia, the carbonic acid being disengaged with effervescence, and the acetate of ammonia remaining in solution. Its Strength must be various, according to the degree of concentration of the vinegar, and hence it is given in divided doses, an ounce being given every hour or two, and its operation promoted by tepid diluents and the sweating regimen. As it produces no increase of vas- cular action, it has been supposed well adapted to ex- hibition in inflammatory fevers, as synocha and acute rheumatism, and it is in such cases that it is usually employed. Its diaphoretic power, however, there is rea- son to suspect, is not very great, though it may be em- ployed perhaps with some advantage when its opera- tion is promoted by the addition of small proportions of opium and antimony. Externally it is used as a discutient, and sometimes as an application to inflamed parts. Citras ammonia. Citrate of Ammonia. - Lemon juice, neutralized by potash, affords a reme- dy, which has long been employed under the name of Saline Mixture, as a refrigerant in fever. When it is neutralized by ammonia, it is supposed, along with its refrigerant, to have a diaphoretic power. Citric acid being the chief constituent ingredient of the juice of the lemon, this preparation is of course a citrate of ammonia. In the diluted state in which the mixture is prepared, it can have no great power; but its diaphore- tic operation is sometimes promoted by the addition of a few drops of tincture of opium and antimonial wine. Carbonas ammonia. Carbonate of Ammonia. This salt is employed either under the solid form, or in a state of solution. In the former state, it is ob- tained by sublimation from a mixture of muriate of ammonia and carbonate of lime, the heat applied giv- ing rise to a double decomposition, and the carbonate DIAPHORETICS. 313 of ammonia being sublimed. It forms a concrete mass, white and efflorescent, which retains the pungent am- moniacal odour, and which, as it also changes the vege- table colours to a green, is probably to be regarded as a sub-carbonate. Its solution (Aqua Carbonatis Am- monias) is prepared by distilling water from a mixture of muriate of ammonia and sub-carbonate of potash, carbonate of ammonia being formed, sublimed, and dissolved by the water which distils over. Under either form it is used as a stimulant, and sometimes as a su- dorific, its dose being 10 or 15 grains of the concrete salt, and from half a drachm to a drachm of the solu- tion. Its operation is promoted by the sweating regi- men. As a stimulant, the solution is given in a similar dose in languor or faintness; and the concrete salt is applied to the nostrils, forming what is named the pun- gent smelling salt. Murias ammonia. Muriate of Ammonia. Sal Ammoniacus. Sal Ammoniac. This salt is prepared by various processes, on a large scale, for the purposes to which it is applied in the arts. The greater number of these consist in ob- taining an impure ammonia from animal substances by distillation, combining it with sulphuric acid, and de- composing this sulphate of ammonia by muriate of soda, the muriate of ammonia formed from the mutual action of these compound salts being sublimed. It is thus obtained in a solid dense mass, somewhat ductile and semi-transparent. It is soluble in about three parts of cold water, and may be crystallized from its hot so- lution. In medical practice it is little employed. It has- been supposed, in the dose of one drachm, to act either as a diuretic or diaphoretic, according to the mqde in which it is administered; the first effect being obtained when the surface of the body is kept cool; the other when external warmth is applied, with the use of tepid diluents. It is also sometimes applied externally as a discutient, dissolved in distilled vinegar. But it has Voi. I. 2R 314 DIAPHORETICS. a place in the Pharmacopoeias principally as being em- ployed in pharmacy. Hydrargyri murias mitis. Sub-murias Hydrargyri. Mild Muriate of Mercury. Sub-muriate of Mercury or Calomel. (Page 277.) v This preparation of mercury is sometimes employed to obtain its action on the cutaneous vessels; and in cer- tain diseases, particularly eruptions on the surface, and chronic rheumatism, has been supposed to prove useful by increasing the insensible perspiration. Combined with opium, or with guaiac, it has been supposed to exert a still greater degree of diaphoretic power. Antimonium. Antimony. (Page 242.) A sympathy appears to exist between the stomach and the surface of the body, in consequence of which, the state of the one is to a certain extent communicated to the other; the nauseating effect, for example, of eme- tics being accompanied with diminished action at the surface. This effect is apparently produced by the pre- parations of antimony; and some of them, particularly the oxide of antimony with phosphate of lime, and the tartrate of antimony and potash, are hence employed as diaphoretics in febrile affections. The former is given in a dose from 5 to 10 grains, repeated every third or fourth hour, until its operation as a sudorific, cathartic or emetic, is produced; the latter being given in a dose of one-half or one-fourth of a grain in a similar manner. The action of both is aided by warm diluents, and some- 'times that of the tartrate of antimony and potash is ren- dered more certain and powerful by combination with opium. The sulphuret of antimony levigated has been employed as a remedy in some cutaneous diseases, and chronic rheumatism; and has been supposed to operate by increasing the insensible perspiration. DIAPHORETICS. 315 Sulphur. Sulphur. (Page 268.) Sulphur, it has already been remarked, passes off by the cutaneous vessels, and with some increase, it has been supposed, of the insensible perspiration. Hence has been explained the advantage sometimes derived from it in habitual dyspnoea, and in chronic catarrh. The so- lution of it in oil, Oleum Sulphuratum, has been used in the same cases, but is a preparation both acrid and nauseous. Opium. Opium. (Page 121.) Opium, in a pretty large dose, produces sweat, par- ticularly when its operation is promoted by diluents and external warmth. It is difficult, however, to employ it alone as a sudorific, from its narcotic power being ne- cessarily exerted at the same time. But by combination with antimony or ipecacuan, a modification of power is produced, more important perhaps than any other aris- ing from the combination of remedies: the narcotic ope- ration of the opium is in a great measure prevented, the nauseating effect of the ipecacuan or antimony is also diminished, and we obtain a sudorific more powerful and certain than any other. In the combination with an- timony, thirty-five drops of antimonial wine are usually added to twenty-five of tincture of opium. The combi- nation with ipecacuan is still more powerful. It is an officinal preparation (Pulvis Ipecacuanhas et Opii), and consists of one part of ipecacuan, one of opium, and eight parts of sulphate of potash; these being rubbed together into a fine powder, the sulphate of potash ren- dering this more easy by dividing the opium, and les- sening its tenacity. This has long been celebrated as a sudorific, under the name of Dover's Powder, and is the medicine which is uniformly employed where copious sweating is to be induced, as in acute rheumatism, in anasarca, and in every other disease in which this indi- cation is to be fulfilled. Its medium dose is ten grains, given generally in a bolus; its operation is promoted by 316 DIAPHORETICS. tepid diluents and external warmth, the patient being confined to bed. If it fail in producing sweat, other five grains may be given at the end of an hour, and some- times even it is necessary to give a larger dose. When it operates, the sweating is generally profuse, and by the proper management can be kept up for several hours. The power of the combination probably depends on the joint action of the opium and ipecacuan, the for- mer increasing the force of the circulation, the latter, by its action, propagated to the surface, diminishing the re- sistence in the exhalant vessels, and causing, therefore, the fluid to be more easily and copiously poured out. Such is the effect of this modification, that the combi- nation can be given with safety in pure inflammatory affections, attended with increased vascular action, where the exhibition of opium alone would be attended with hazard. Camphora. Camphor. (Page 118.) Camphor has been employed as a diaphoretic in acute rheumatism, in different forms of fever, and in several of the exanthemata, particularly small pox, in a dose from 5 to 15 grains. Its operation as a sudorific is not sufficiently certain, however, when it is given alone. Sometimes it is combined with nitre, with antimonials, mild muriate of mercury or opium. Guaiacum officinale. Guaiac. Decand. Monogyn. Gruinales. Lignum et Gummi resina. South America and West Indies. The wood of this tree, and a concrete resinous sub- stance obtained by exudation from incisions in its trunk, are the parts of it used in medicine. The wood is hard and heavy, of a yellowish colour, has little smell, and a slightly warm bitter taste. Its vir- tues depend on the small portion of resinous matter which it contains. Guaiac wood was introduced into practice as a re- medy in the treatment of lues venerea, and was at one time even considered capable of effecting a radical cure. DIAPHORETICS. 317 Its powers are now better ascertained. It is employed merely as an auxiliary, and sometimes with advantage, in promoting the action of mercury in the confirmed state of the disease, and in alleviating the various symp- toms which arise from a protracted mercurial course. It is likewise occasionally prescribed in cutaneous dis- eases, in scrofulous affections, and in chronic rheuma- tism. The form under which it is administered, is always that of decoction, for which a formula is given in the Pharmacopoeias. A quart of this is drunk in the course of the day. If taken warm it produces dia- phoresis. Offic. Prep.—Dec. Guaiac. Off. Comp. Ed. Guaiacum. Gummi-Resina. This is obtained by exudation from incisions made in the trunk of the guaiac tree. It is friable, of a green- ish or grayish colour, and resinous lustre, has an odour somewhat fragrant, and a warm bitterish taste. It was usually regarded as a gum resin, but the experiments of Mr. Brande have shown that it possesses some pe- culiar properties, whence it has been regarded as a dis- tinct principle. It is very liable to changes of colour, apparently from the action of oxygen. Its powder is at first of a gray colour, but becomes green from expo- sure to the air; and when its solution in alkohol is de- composed by acids, the precipitate assumes various tints of colour. When acted on by concentrated nitric acid, it affords oxalic acid; by the diluted acid a pro- duct is formed more highly resinous. It is almost en- tirely soluble in alkohol. Water by digestion on it dis- solves a little extractive matter. Guaiac is a stimulating medicine, proving diaphore- tic in a dose of about half a drachm, and purgative in a larger dose. It is a remedy employed in chronic rheu- matism, being given so as to excite sweat, or more usually in smaller doses to keep up a gentle diaphore- sis. Its sudorific power is promoted by opium or the preparations of antimony. It is given either in sub- 318 DIAPHORETICS. stance in the form of bolus, or diffused in water by the medium of mucilage, or in tincture. The tinctuie of it in spirit of ammonia is more highly stimulating than that in proof-spirit, and is generally preferred. Offic. Prep.—T. Guajac. T. Guajac. Amm. Edin. Lond. Dub.—Mist. Guaiac. Lond. Daphne mezereum. Mczereon. Pentand. Monogyn. Veprecule. Cortex radicis. Indigenous. The bark of the root of this plant is the part of it used in medicine: its taste when it is chev/ed for some time is extremely acrid; but this acrimony is somewhat impaired by drying; it is extracted by water and by vi- negar. Mezereon is a stimulating diaphoretic, which, by de- termining to the surface of the body, has been found of service in chronic rheumatism, and in cutaneous dis- eases. Its principal medicinal application has been in syphilis; and it has been regarded as peculiarly effica- cious in removing venereal nodes, and thickening of the ligaments and periosteum, and in disposing ulcera- tions' to heal. It is given in the form of decoction; 2 drachms of the bark, with half an ounce of liquorice root, being boiled in 3 pounds of water, to 2 pounds, and 4 or 6 ounces of this decoction being given four times a-day. From its acrimony it is somewhat liable to excite nausea, hence it is often given in a weaker decoction, and combined with guaiac and sarsaparilfa. Such a combination forms the Decoctum Sarsaparillae Compositum, an improved formula for the Lisbon diet drink, which has been so highly celebrated in the treat- ment of these affections. Offic. Prep.—Dec. Daphn. Mez. Ed. Laurus sassafras. Sassafras. Enneand. Monogyn. Oleracee. Lignum. America. This wood has a moderately fragrant smell, and a sweetish aromatic taste. It affords an essential oil by distillation, and yields to water, by infusion or decoc- EXPECTORANTS. 319 tion, its flavour, and part of its taste. It is slightly sti- mulant and diaphoretic. Its infusion has been drunk freely in cutaneous diseases, and in chronic rheuma- tism; and it is frequently added to decoctions of sarsa- parilla, guaiac and mezereon, probably without com- municating any real virtue. Offic. Prep.—Ol. Laur. Sassaf. Ph. Ed. Salvia officinalis. Sage. Diand. Monogyn. Verticillate. Folia. South of Europe. The leaves of this shrub have an aromatic smell, and a warm bitterish taste. Its aqueous infusion drunk warm, has been used to produce sweat, or to promote the action of sudorifics; the aromatic quality of the sage adding something perhaps to the power of the warm diluent. CHAPTER XII. OF EXPECTORANTS. Expectorants have been defined, those medicines which facilitate, or promote the rejection of mucus, or other fluids from the lungs and trachea. The theory that has been given of their mode of operation is ex- tremely obscure and hypothetical. It has been supposed, that in certain diseases, a greater quantity of serous fluid is thrown out by the exhalant vessels in the lungs than the absorbents can take up, and that expectorants facilitate the rejection of this fluid. But as expectora- tion of this kind is a complicated, and partly voluntary operation, dependent on the action of a variety of mus- cles, it is difficult to perceive how these remedies can produce this effect. There are only two classes of me.- 320 EXPECTORANTS. dicines which seem capable of promoting expectora- tion in this manner: powerful stimulants, which, when extreme debility is present, may promote it by giving vigour to the voluntary muscles exerted in this opera- tion, and emetics, which, by exciting vomiting, com- press the thoracic viscera, and by calling all the neigh- bouring muscles into strong action, and rendering both expiration and inspiration more forcible, may facilitate the expulsion of matter from the cavity of the lungs. But these exert no specific action, and are therefore not entitled to the appellation of expectorants; nor indeed are they usually considered as such. If, therefore, by expectorants, are understood sub- stances capable of promoting, by some specific action on the parts concerned, the expulsion of fluid from the lungs, there seems no reason to believe in the existence of such remedies. Dr. Cullen, after admiting the difficulty of giving a satisfactory theory on this subject, supposes that the promoting of expectoration by these remedies may be owing to their " increasing the secretion of the liquid, that is, to afford a mucus: this, as it is poured from the arteries into the follicles, being always a thin fluid, it may dilute the mucus in the follicles, and may cause it to be poured out from these in a less viscid state, and thereby render it more easy to be brought up by cough- ing, that is, to be more freely expectorated." It is possible that some expectorants may act in this manner; but the action of the different individuals be- longing to the class, and especially their action in diffe- rent diseases, cannot always be explained on this prin- ciple. It is probable that there are several modes of operation, in which certain medicines may appear to promote expectoration, and which may give them a claim to the title of expectorants. In the first place, by removing constriction on the exhalant vessels in the lungs, expectoration will appear to be promoted. From this constricted state, the usual quantity of fluid is not thrown out to lubricate these parts: expectoration must of course be more scanty than usual; and if medicines be given capable of removing EXPECTORANTS. 321 the constriction, expectoration will become more co- pious. At the same time, the disease will be at least partially relieved, as that morbid state of the vessels, from which some of its symptoms originate, is re- moved. It is apparently by such a mode of operation that the promoting of expectoration is of service in pneumonia, catarrh, and asthma, the principal diseases in which expectorants are employed. The remedies by which such an effect is induced, according to this mode of operation, must be principally those belonging to the class of antispasmodics, or those which have the power of inducing nausea, either of these being capable by their action of removing constriction of the exhalant vessels. It is not possible, however, to reduce all the medicines ranked as expectorants to this mode of operation. On the contrary, some of them seem to act on a very differ- ent principle. In certain diseases, as in humoral asthma and catarrhus senilis, there seems to be, from debility of the exhalants, or from deficient action of the absor- bents, an increased quantity of fluid in the lungs. There appears to be certain substances more peculiarly deter- mined to the pulmonary vessels, as their odour is dis- cernible in the air expired. These may stimulate the exhalant vessels through which they pass, and by this stimulus may moderate the effusion of fluid, and thus render the expectoration of the remainder more easy. Any medicine promoting absorption of this effused fluid, will to a certain extent have a similar effect. There is still another mode in which the quantity of fluid in the lungs may be diminished, that of determin- ing to the surface of the body, so as to increase the in- sensible prespiration; and it is probable, that some of the substances which have been used as expectorants, particularly those connected with the class of diaphore- tics, owe what virtues they have to this operation. Expectorants are not then to be regarded as medi- cines, which assist the rejection of a fluid already secre- ted, or which, according to Dr. Cullen's opinion, alter its consistence, and render it thin where it is too viscid, by Vol. I. 2S 322 EXPECTORANTS. which its explusion is rendered more easy. They are rather to be considered either as increasing the natural exhalation, where it has been deficient, in which case the expectoration that takes place is the consequence of this, and not the cause of any relief that is afforded; or as diminishing the quantity of fluid where it is too copi- ous, either by stimulating the exhalant vessels, increasing -the action of the pulmonary absorbents, or determining to the surface of the body, by which diminution the expulsion of the remaining fluid is facilitated. On one or other of these principles, we may, with sufficient proba- bility, explain the effects of this class of remedies, and their application to the treatment of diseases. From this difference in the mode of operation of ex- pectorants, it is evident that they will prove useful in opposite diseases, and that in some diseases advantage may be derived from those belonging to one division, but not from the others. In pneumonia, where the expectoration is deficient, as this arises not from any deficiency of power to expec- torate, but from a diminution of the fluid usually thrown out into the bronchia?, owing to a constricted state of the exhalant vessels, it is evident that those expec- torants, which act by removing such a state, will be most useful, while such expectorants as stimulate these vessels would be rather prejudicial. Hence the utility in such cases of nauseating doses of tartrate of antimony, or of ipecacuan; and similar advantage may be derived from their use in catarrh, and perhaps also in spas- modic asthma. On the contrary, where the effusion of fluids into the bronchiae is too great, as in humoral asthma, or in the chronic cattarrh to which old people are subject, those expectorants which are more directly stimulant, as the different balsams, and several of the gum-resins, as myrrh or ammoniacum, ro those which promote absorption, as squill or foxglove, will be found more useful. In considering the particular expectorants, they may be arranged as nearly as possible according to these subdivisions. 323 EXPECTORANTS. Antimonium. Ipecacuanha. Digitalis purpurea. Nicotiana tabacum. SciLLA MARITIMA. Allium sativum. polygala senega. Ammoniacum. Myrrha. Myroxylon PERUIFERUM. Toluifera balsamum. Styrax benzoin. Styrax officinale. Amyris gileadensis. Antimonium. Antimony. (Page 243.) Of the preparations of antimony which have been employed as expectorants, the principal are the hydro- sulphuretted oxide, and the tartrate of antimony and potash. The first, under the forms of what are named Kermes mineral, and golden precipitate of antimony, was at one time celebrated as a remedy in pertussis and in pneumonia, in a dose of from 5 to 10 grains; but being uncertain in its strength, has fallen into dis- use. The tartrate of antimony and potash is used in the same cases, and in some forms of asthma and catarrh, in the dose of one-eighth of a grain, repeated every se- cond or third hour. It is also frequently combined with squill and other expectorants. Ipecacuanha. Ipecacuan. (Page 253.) Ipecacuan, operating in the same manner nearly as antimony, has like it been used as an expectorant in a dose of two or three grains. It is, however, less fre* quently employed. 324 EXPECTORANTS. Digitalis purpurea. Foxglove. (Page 138.) Digitalis is employed with much advantage in humoral asthma,—dyspnoea aquosa, and in catarrhus senilis, obviously from its power of promoting absorp- tion, by which it removes the fluid accumulated in the lungs apparently from diminished action of the absorb- ents. By diminishing the quantity of this fluid, it faci- litates the expectoration of the remainder, and hence appears to act as an expectorant, and it relieves the difficulty of breathing, and the irritation to which its accumulation gives rise. In such cases, it is proper to give it rather in small doses, than to push its operation to any great extent; a grain of the dried leaves, or half an ounce of the infusion daily, will be a sufficient dose. Nicotian a Tabacum. Tobacco. (Page 143.) Tobacco has been celebrated as an expectorant in chronic catarrh and humoral asthma, under the form of the watery extract, the dose of which is two or three grains. Its general action being similar to that of fox- glove, it no doubt operates in these morbid affections 6n the same principle, though probably much inferior to the other. Scilla maritima. Squill. (Page 255.) Sojiill, next to its employment as a diuretic in dropsy, is most frequently used as an expectorant; and it is more particularly in those cases where there is an accumulation of the pulmonary mucus that it is pre- scribed; hence it probably operates by its power of pro- moting absorption. In inflammatory states of the sys- tem, where, from constriction of the pulmonary vessels, the exhalation is diminished, it is probably less useful; it has even been considered injurious in pneumonia, unless when combined with tartrate of antimony. As an expectorant, it is also used in pertussis, and in that disease is frequently given in such a dose as to produce vomiting. In all these cases it is generally used under EXPECTORANTS. 325 the form of the vinegar or syrup of squill, the dose of the former being half a drachm, of the latter a drachm, repeated every third or fourth hour. The squill pill is sometimes used in chronic catarrh in a dose of 10 grains daily. Allium sativum. Garlic. Hexand. Monogyn. Liliacee. Radix. South of Europe. The root of this plant, which is of the bulbous kind, has, when recent, a foetid smell and acrid taste. By being long kept it becomes shrivelled and inert. Its taste and smell are extracted by water by infusion; by decoction they are nearly lost. By distillation it affords an essential oil odorous and acrid. Garlic has a considerable analogy to squill, and its operation is probably nearly the same: it acts as a diu- retic, diaphoretic, and expectorant; hence its use in dropsy, rheumatalgia, and humoral asthma. Its dose is half a drachm or 2 scruples, swallowed whole, or made into pills with soap. A syrup prepared by digesting it in vinegar, and boiling the liquid with the due propor- tion of sugar, has been used as an expectorant. Exter- nally garlic bruised is applied as a stimulant and rube- facient. Offic. Prep.—Syr. Alii, Ph. Dub. Polygala senega. Seneka. Rattlesnake-root. Diadelph. Oc- tand. Lomentac. Radix. North America. This root is in articulated shoots, of a grayish yel- low colour; its taste is bitter and pungent. Its active matter is extracted partially by water with the assistance of heat, and completely by alkohol. Seneka has been frequently employed as an expecto- rant in pneumonia, after the highly inflammatory stage of the disease has been subdued. Its dose in substance is from 10 to 20 grains, but it is generally used in the form of decoction, of which, when prepared according to the formula of the Edinburgh College, an ounce, or an ounce and a half may be given every second or 326 EXPECTORANTS. third hour. As it operates also as a diuretic, it is pro- bable that its efficacy depends on its power of increas- ing absorption, and hence that it is more adapted to those cases where there is an accumulation of fluid in the bronchia?, than to affections of an opposite nature. Offic. Prep.—Dec. Polygal. Seneg. Ed. Lond. Ammoniacum. Ammoniac. Gummi-resina. This gum-resin is brought from Egypt and the East Indies; the tree which produces it having not been ac- curately known. The London College have now, on the authority of Wildenow, designated it as the Heracleum Gummiferum, this having been raised by that botanist from the seeds often found mixed in the gum ammo- niac of the shops. It is in large masses, or, when of the best quality, in small round fragments, yellow on the surface, and white within. It has a faint smell, and a nauseous taste. It is partially soluble in alkohol. Water triturated with it forms a milky-like mixture, from which, on standing, a resinous matter subsides. Gum-ammoniac is principally employed as an expec- torant, and is frequently prescribed in asthma and chro- nic catarrh. Its dose is from 10 to 30 grains; either given under the form of pill, or diffused in water, and frequently combined with squill or tartrate of antimony. Externally it is applied as a discutient, under the form of plaster, to white swelling of the knee, and to indo- lent tumors, being beat into a soft mass with vinegar, and spread on leather. Offic. Prep.—Emp. Amm. Emp. Ammon. cum Hydr. Lond.—Mist. Ammon. Lond. Dub. Myrrha. Myrrh. Gummi-resina. Myrrh is the produce of Arabia and Abyssinia; the plant from which it is obtained has never yet been ac- curately described. It is in small irregular pieces of a reddish brown colour, has a smell rather fragrant, and a warm bitter taste. It consists of gum and resin; the latter appearing to constitute its active matter. Alkohol EXPECTORANTS. 327 dissolves the resin, and the solution is rendered turbid by the affusion of water. Water boiled on the myrrh dissolves the gummy matter, to which part of the resin adheres, and this evaporated affords the watery extract, which is less active than the myrrh itself. Myrrh is an expectorant, which has been regarded as too stimulating to be employed in pneumonic in- flammation, but which has been often employed in asthma and chronic catarrh, and sometimes in phthisis. Its dose is from 10 to 20 grains. The watery extract, which has been preferred by many physicians to the myrrh itself, and which is the form under which it has been used in phthisis, seems to be an injudicious pre- paration, as the myrrh is merely weakened in power. Myrrh is also sometimes employed in amenorrhoea. Its tincture is in common use as a stimulating application in sponginess of the gums, and sometimes also to foul ulcers. Offic. Prep.—Tinct. Myrrh. Ph. Ed. Lond. Dub. Myroxylon peruiferum. Balsamum Peruvianum. Peruvian Balsam. Decand. Monogyn. Lomentacee. South America. This balsam is said to be extracted by boiling the bark and young branches of the tree with water; it has * also been affirmed that it is obtained by exudation. It is thick and viscid, of a reddish-brown colour, has a strong smell somewhat fragrant, and a bitter pungent taste. It affords a small portion of essential oil by dis- tillation, and of acid of benzoin by sublimation. Its re- maining matter is resinous. It is entirely soluble in alkohol. Peruvian balsam is considerably stimulant. It has been employed as an expectorant in catarrh and dysp- noea, more particularly in those forms of these diseases where the secretion of pulmonary mucus is increased, and may perhaps be of some advantage in stimulating the exhalants or absorbents. It has likewise been pre- scribed as a remedy in paralysis, chronic rheumatism, and leucorrhoea. Its dose is from 5 to 15 grains, and it 328 EXPECTORANTS. is best given diffused by mucilage, or made into pills by anv vegetable powder. Offic, prep.—T. Bals. Per. Lond. Toluifera balsamum. Balsamum Tolutanum. Balsam of Tolu. Decand. Monogyn. Lomentacee. South America. Tolu balsam is obtained from incisions in the trunk of the tree; it thickens, and in time becomes concrete, and of a resinous fracture and appearance; it has a fra- grant odour, and a warm sweetish taste. It dissolves entirely in alkohol, and communicates its odour and taste to water by boiling. It contains a small quantity of acid of benzoin. This is the mildest of all the balsams. It has been used as an expectorant, and its tincture or syrup some- times enters into the composition of mucilaginous mix- tures used in catarrh, but its powers are very inconsi- derable, and it is employed principally on account of its flavour. Offic. Prep.—Syr. Toluif. Bals. Ph. Ed. Lond.— Tinct. Toluif. B. Ed. Dub. Styrax benzoin. Benzoinum. Benzoin or Benjamin. Decand. Monogyn. Bicornes. Balsamum. India. This balsam is obtained by exudation; it is in brittle masses, composed of brown and white fragments; its smell is fragrant; it has little taste. It consists almost wholly of resin, and is therefore nearly entirely soluble in alkohol. It likewise contains a considerable portion of that peculiar acid, which, as it exists in greater quan- tity in it than in any other vegetable matter, is named Benzoic acid. This is obtained from it by sublimation, or by decoction with water, and likewise by boiling it with potash or lime, with either of which it combines, and is afterwards separated by the addition of an acid. It is in white brilliant scales, retains the flavour of the benzoin, and with acidity has likewise a degree of pun- gency. Benzoin is rarely employed in medicine. Its acid is EXPECTORANTS. 329 used as an expectorant in asthma, in a dose of 10 or 15 grains; but it is probably a medicine of little power. It enters into the composition of the ammoniated and cam- phorated tinctures of opium, and is scarcely applied to any other use. Offic. Prep.—T. Benz. C. Ed. Lond. Dub. Styrax officinale. Storax. Decand. Monogyn. Bicornes. Bal- samum. South of Europe, Asia. This substance is in masses soft and slightly unctu- ous, of a brown colour, with scarcely any resinous lus- tre or appearance; it has a strong fragrant odour, and a bitterish pungent taste. It consists principally "of resin, with a small portion of benzoic acid. It resembles ben- zoin in its virtues; was formerly used as an expecto- rant, but is now little regarded. The purification of it, ordered in some of the Pharmacopoeias, is altogether superfluous. Offic. Prep.—Styrax. Purif. Ph. Lond. Dub.—V\\. Styrac. Dub. Amyris gileadensis. Balsamum Gileadense. Balsam or Balm of Gilead. Octand. Monogyn. Dumose. Arabia. t This balsam, obtained by incisions made in the trunk of the tree, is in the form of a milky juice, highly fragrant, and is so much valued in the East, that it is said not to be imported into Europe. A coarser kind is obtained by strong decoction of the branches and leaves, of a yellow colour, and thick consistence; its taste is warm and bitter; its flavour somewhat fragrant. What is met with in the shops, under the name of Balsam of Gilead, is a resinous juice having none of these quali- ties, and probably the produce of a different plant. It seems little superior to the finer kinds of turpentine. The medicinal virtues of the genuine balsam of Gi- lead have been very highly extolled, undoubtedly with much exaggeration. The common balsam is scarcely used; but its qualities seem to be similar to those of the balsam of Peru, with more acrimony. Vol. I. 2 T 330 CHAPTER XIII. OF SIALAGOGUES. Sialagogues are substances which increase the sa- livary discharge. This may be effected either by the mastication of substances, which, by their acrimony and pungency, excite the action of the vessels which secrete the saliva, or by the internal exhibition of certain medi- cines. Of the latter, mercury is the only certain siala- gogue; and all its preparations, when administered in certain quantities, produce salivation to a greater or less extent. As a class of remedies, sialagogues are of little im- portance. The sialagogue operation of mercury, it has already been remarked, does not appear essential to its efficacy in any disease, but is regarded merely as a test of the mercury acting on the system. The acrid siala- gogues, by increasing the secretion of saliva, and by their pungency, sometimes relieve the pain of toothach, • and have been supposed useful, by the derivation they occasion, in some kinds of headach. SIALAGOGUES. Hydrargyrus. Anthemis Jyrethrum. Arum maculatum. cochlearia armoracia Daphne mezereum. Amomum zingiber. NlCOTIANA TABACUM. SIALAGOGUES. 331 Hydrargyrus. Quicksilver. (Page 164.) No satisfactory explanation has been given of the pe- culiarity which mercury, under every form of prepara- tion, has of exciting the secretion of the saliva. Some have remarked, that in consequence of the gravit) of this metal, by which, when received into the circula- tion, it is disposed to retain the " direct line in which it is propelled from the heart, it is more certainly deter- mined to the vessels of the head," a solution of the dif- ficulty which is altogether absurd. It has likewise been supposed to act by lessening the consistence of the blood, and disposing it to pass more easily into the sa- livary glands, so as to increase their secretion,—an opi- nion equally gratuitous and improbable. Dr. Cullen en- deavoured to solve the problem, by supposing that mercury has " a particular disposition to unite with am- moniacal salts, and that such salts are disposed to pass off by the salivary glands more copiously than by any other excretion." But mercury has no peculiar tenden- cy of this kind; and if it had, these salts are not more abundant in the saliva, than in some other secretions. If another hypothesis might be hazarded, the following perhaps would afford some explanation of this singular property. The urine appears more peculiarly designed to convey matter which has been received into the cir- culating mass, but which is still excrementitious, from the system. To pass, however, with this fluid, it is necessary that the matter conveyed should be soluble in it; and when it is so, we can discover it in the secretion by chemical tests. If there is any property connected with it, therefore, which shall prevent this solubility, it probably will prevent the substance from being secret- ed. Now, the phosphoric acid, abundant in urine, must in this mode counteract the secretion of mercury in any form of preparation, by forming with it a compound insoluble, and to which the slight excess of acid cannot communicate solubility. The mercury, therefore, ex- isting in the circulating mass, when brought, in the 332 SIALAGOGUES. course of the circulation, to the secreting vesseh of the kidneys, will not pass through their whole course, but if conveyed so far as to be combined with phosphoric acid, will, from this combination, be incapable of being conveyed onwards, and will therefore be retained in the composition of that part of the blood which does not enter into the secretion, but returns into the circulation. It must be discharged by some other emunctory: a por- tion of it appears, from some facts, to pass off by the insensible perspiration; but the tenuity of this secretion, if the term may be employed, mu^t be unfavourable to this mode of discharge. The salivary secretion is one by which it may be more easily transmitted; and this transmission may even be facilitated by the affinity ex- erted to the oxide of mercury by the muriatic acid, the soda and ammonia, which are the chief saline ingredi- ents in saliva; for it deserves to be remarked, that triple compounds of these substances,—a soda-muriate, and ammoniaco-muriate of mercury, are to a certain extent soluble in water; and if the mercury is thus secreted, it will of course stimulate the secreting vessels through which it passes, and increase the discharge. The increase in the salivary discharge, effected by mercury, is attended with pain and a sense of heat in the mouth, with softness and swelling of the gums, and sometimes with slight ulceration, or with a consider- able degree of swelling, extending over the throat and face. These effects, when excessive, are best checked by the use of opium, of purgatives, of a blister applied to the throat, and, as Mr. Pearson has recommended, free exposure to a cool dry air. From theory, the admi- nistration of sulphur, or sulphuret of potash, has also been recommended. The remaining Sialogogues act only by topical appli- cation. Anthemis pyrethrum. Pellitory of Spain. Syngenes. Polygam. superfi. Composite. Radix. South of Europe. This root, though cultivated in this country, is ge- SIALAGOGUES. 333 nerally imported from Spain. In taste is hot and acrid, its acrimony residing in a resinous principle, which al- kohol dissolves, forming a very acrid tincture. It is a remedy which, from stimulating the salivary glands, and exciting a discharge of saliva, is used in toothach, and sometimes gives relief. It has also been chewed in palsy of the muscles of the throat. Arum maculatum. Wake-Robin. Gynand. Polyand. Piperite. Radix. Indigenous. The root of this plant, when recent, is extremely acrid; by drying, its acrimony is much impaired. In di- gesting it with alkohol, or with water, and evaporating either solution, an extract is obtained less acrid than the root itself, the vapour condensed has not much acri- mony, and hence the principle in which this property resides appears to be one very easily decomposed. It resembles pellitory, and may be applied to the same purposes, but its pungency is unpleasant. Internally, it has sometimes been used as a stimulant in palsy and rheumatism. Cochlearia armoracia. Raphanus rusticanus. Horse-radish, Tetradyn. Silic. Siliquose. Radix. Indigenous. Th e root of this plant, when recent, has a penetrat- ing taste, with a degree of sweetness. It excites, when chewed, a sense of heat, and a discharge of saliva. Its pungency resides in an essential oil, and is therefore lost by drying. Water and alkohol may be impregnated with it. Horse-radish is a stimulant, which, as a sialagogue, has been used in paralysis of the tongue. It has also been used internally in paralysis and rheumatism, in asthma and dropsy, about a drachm of the recent root cut in small pieces being swallowed entire. Externally it has been applied as a rubefacient, and its syrup has been used as a remedy for hoarseness. Offic. Prep.—Infus. Armorac. Comp. Lond. Dub. —Spir. Armorac. Comp. Ph. Lond. 334 SIALAGOGUES. Daphne mezereum. Mezereon. (Page 318.) The bark of the root of mezereon has a very consi- derable degree of acrimony, so that when chewed it impresses a sense of heat and irritation in the mouth and upper part of the throat, and at the same time ex- cites the salivary discharge. As a sialagogue, however, it is scarcely used. Amomum zingiber. (Page 208.) Ginger-root, from its pungency, excites, when masticated, a sense of heat and increased discharge of saliva, and is sometimes, like other sialagogues, em- ployed to relieve the pain of toothach. Nicotiana tabacum. Tobacco. (Page 143.) Tobacco, when chewed, increases the action of the salivary glands, and the same effect is produced in the usual method of smoking it. Partly from this, and part- ly from its narcotic operation, exerted at the same time to a certain extent, it sometimes relieves, especially in the latter mode of using it, the pain of toothach, or of ear-ach. CHAPTER XIV. OF ERRHINES. Errhines or Sternutatories, are substances which occasion a discharge from the nostrils, either of a mu- cous or serous fluid. They all operate by direct appli- cation, and generally in consequence of a slightly acrid quality. Any substance in fine powder snuffed up the nostrils has this effect in a certain degree; but it is, as is to be expected, more copious as the substance is ERRHINES. 335 more acrid or stimulating. The discharge, as produced by different errhines, varies in extent, and in the time during which it continues. Some also occasion a sense of heat, or even inflame the membrane to which they are applied, while others have no such effects. It is evident, that the effects of this class of remedies must be very limited, as applied to the treatment of dis- ease. By the evacuation they occasion, it has been sup- posed that they diminish the quantity of fluid circulat- ing in the neighbouring vessels; hence they have been inferred to be useful in rheumatic affections of the mus- cles of these parts, and in toothach. It has even been supposed, that their effects may extend to all the branches of the external carotid, and Dr. Cullen men- tions, that he has, apparently from this operation, known headach, pain of the ear, and some cases of ophthalmia, cured or relieved by the use of errhines. He has like- wise supposed, that they may have been of use in pre- venting apoplexy or palsy: this at least should, he re- marks, be so far attended to, that whenever any ap- proach to these diseases is suspected, the drying up of the mucous discharge should be attended to, and if possible obviated. ERRHINES. Iris florentina. ^kfoS'.ULUS HII'POCASTANUM. •Origanum majorana. Lavandula spica. Rorismarinus officinalis. asaiu'm europ£lm. Veratkum album. Nicotiana tabacum. Euphorbia officinalis. Sub-sulphas hydrargyri. 336 ERRHINES. Iris tlorentina. Florentine Orris. Triand. Monogyn.—Ensatr. Radix. South of Europe. The root of this plant, freed from its outer bark, is of a white colour, has a pleasant odour, and slightly bitter taste. It is a mild sternutatory, and enters into the composition of some cephalic snuffs. .£sculus hippocastanum. Horse Chesnut. Heptand. Monogyn. Trihilate. Semen. Cortex. The fruit of this tree is principally farinaceous; and this farina acts as a sternutatory. The bark is bitter, and has been proposed as a substitute for Peruvian Bark. Origanum majorana. Sweet Majoram. Didynam. Gymnosperm. Verticillate. Herba. South of Europe. Th e leaves of this herb have an aromatic odour, and, when dried and reduced to power, a slight errhine power. Rosmarinus officinalis. Rosemary. Diand. Monogyn. Verticil- late. Summitates florentes. Th e flowers and flowering tops of this plant have a fragrant odour, which resides in an essential oil. It is used as a stimulating perfume, under the form of the distilled spirit, and the powder is sometimes mixed with other errhines. Offic. Prep.—Ol. Ess. Rorism. Spirit. Rorism. Ph. Lond. Dub. Ed. Lavandula spica. Lavender. Didynam. Gymnosperm. Verticil- late. Spice florentes. South ofEurojf). >, Lavender flowers have a fragrant smell, and a warm bitterish taste. They yield a quantity of essential oil, which is employed in medicine as a stimulant, when combined with alkohol, and other aromatics, under the form of what is named Compound Spirit of Lavender. The simple spirit or solution of the oil in alkohol is ERRHINES. 337 used as a perfume, and the dried leaves in powder are errhine.. Offic. Prep.—Spir. Lavand. T. Lav. C. 01. Lavand. Ph. Ed. Lond. Dub. Nicotiana. Tobacco. (Page 143.) The leaves of tobacco are in common use as an errhine; their powder forming the different kinds of snuff. Asarum europium. Asarabacca. Dodecand. Monogyn. Sarmcnta- cee. Folia. Indigenous. The leaves of this plant possess rather more errhine power than those hitherto noticed, and are employed as the basis of the officinal sternutatory powders. Offic. Prep.—?. Asar. Europ. C. Pharm. Ed. Dub. Veratrum album Helleborus Albus. White Hellebore. Poly- gam. Moncec. Liliacee. South of Europe. The root of this plant has a strong disagreeable smell when fresh, which is lost by drying, and an acrid taste which is retained. Snuffed up the nostrils in very - small quantity, it excites violent sneezing, with a sense of heat, and a copious discharge of thin mucus. It is therefore sometimes used as a sternutatory mixed with some of the milder and more fragrant errhines. Taken internally, in the dose of a few grains, it acts as a vio- lent emetic and cathartic. Externally, when mixed with lard, so as to form an ointment, or in the form of de- coction, it is used as an application in some cutaneous Offic. Prep.—T. Verat. A. Ed.— Dec. Verat. Ungt. Verat. Lond.—Ung. Helleb. A. Dub. Euphorbia officinalis. Dodecand. Trigynia. Gummi-resina. Africa. This substance, which is of a resinous nature, is said to be obtained by exudation from incisions in th© branches of the plant producing it. It js in small round Vox. I» 2 U 338 RUBEFACIENTS fragments, having scarcely any smell, but a very acri- monious taste. Its operation as a drastic purgative is so violent, that it is never given internally. Its powder is the most violent of all the errhines, occasioning a co- pious discharge of mucus, with a sense of heat, and even inflammation. Hence it is scarcely ever employ- ed. Externally it has been used as a rubefacient or ve- sicatory. Sub-sulphas hydrargyri. Sub-Sulphate of Mercury. This preparation of mercury is an errhine, and has been employed in chronic ophthalmia and amaurosis; one grain of it being mixed with six or eight grains of any mild vegetable powder, and snuffed up the nostrils occasionally. CHAPTER XV. RUBEFACIENTS AND EPISPASTICS. Rubefacients and Epispastics operate nearly on the same principle, and produce similar effects, differ- ing only in degree. They may therefore be considered as sub-divisions of one class. The term Epispastic has been applied to whatever application has the power of producing a serous or pu- nform discharge, by exciting a previous state of in- ilammation or suppuration. The term includes blisters, issues and setons; but it is more commonly restricted to the first of these, and it is this which chiefly falls un- der the department of Materia Medica. Blisters are those external applications which excite inflammation on the skin, and which, occasioning a thin AND EPISPASTICS. 339 serous fluid to be poured from the exhalants, separate the cuticle from the true skin, and form the appearance of a vesicle or blister. The mode in which they produce this effect is suffi- ciently evident; it is to be referred to the stimulating power of the substances applied, which exciting in- creased action in the extreme blood-vessels, induces in- flammation, and causes the pouring out of the serous fluid with which the vesicle is filled. Hence we deduce the primary effects of these applications on the general system. By the increased action they excite, and the pain they occasion, they act as stimulants, and they may act, it has been supposed, as evacuants, by the quantity of fluid which they cause to be poured out. There can now be little dispute by which of these modes of operation blisters are used with advantage in the treatment of diseases. The quantity of fluid dis- charged is so inconsiderable, and the relief obtained often so sudden and complete, that it would be assign- ing a very inadequate cause for their effects, if we should ascribe these to any evacuating power. Some have imagined that cantharides, which forms the basis of the common blistering applications, are ab- sorbed in part by the inflamed surface, and that it is to the peculiar action of this acrid matter stimulating the system, that many of the effects of blisters are owing. But there is no proof, nor indeed any reason to believe, that this absorption is uniform or frequent; the same effects are obtained from blistering applications into the composition of which cantharides do not enter, while they are not obtained from the internal administration of cantharides. The effects of blisters are therefore to be ascribed to the pain and inflammation they excite, and the stimulus which is thence propagated to the ge- neral system. It is a principle with regard to the living body, de- monstrated by many facts, that where a morbid action exists, it may be often removed by inducing a different action, even of a morbid kind, in the same part, or in 340 RUBEFACIENTS parts as contiguous to it as possible; and where the morbid .action extends to the whole system, it may be removed by one of a different kind being excited either generally, or in any particular part of the body. From thl> principle is explained the efficacy of blis- ters in all cases of inflammation and spasmodic con- striction; a new inflammation being excited by the blis- ter which occasions derivation of action. Hence, too, the advantage obtained is greater when the blister is applied as near as possible to the part affected. This principle regulates the application of blisters in pneu- monia, hepatitis, phrenitis, angina, ophthalmia, rheuma- tism, and every other case of active inflammation. In these affections, blisters are used with evident advan- tage; the local inflammation which is excited more than counterbalancing, by this operation, the stimulant effects at the same time produced. A similar principle exists with respect to the pain excited by blisters, which may also be applied to the explanation of the advantages derived from them in other diseases. It has long been remarked, that excit- ing one pain often relieves another, and hence blisters afford relief in toothach, and other painful affections. Epilepsy and hysteria arising from irritation have been removed by blisters; apparently from their exciting pain, engaging the attention, and diminishing the sen- sibility to irritation. Lastly, blisters exert a stimulant operation on the general system, and raise the vigour of the circulation. Hence their utility in fevers of the typhoid kind, where extreme debility prevails. From their peculiar opera- tion too, they are the only remedy that can be used to obviate the local inflammation of the brain, or other parts, that sometimes exists in fevers of this kind, as th«y contribute to resolve it without reducing the strength of the system. It is also from their stimulating power, and perhaps from exciting pain, that blisters are of advantage in apoplexy and paralysis. AND EPISPASTIGS, 341 Rubefacients operate precisely in the same man- ner as blisters; they excite pain and inflammation, but only in an inferior degree, so that no fluid is discharg- ed; and by these effects they more peculiarly obviate local inflammation. They are used, therefore, for the same purposes. EPISPASTICS AND RUBEFACIENTS. Meloe vesicatorius. Euphorbium. Pix burgundica. Sinapis alba. Allium sativum. Ammonia. Cantharides. Meloe Vesicatorius. Lytta Vesicatorla. Under the history of this substance as a diuretic, it has been remarked, that it is a still more important article of the Materia Medica as an epispastic. It is the substance, indeed, which is now almost exclusively employed to raise a blister, as it acts with certainty, and is not liable to induce that deep-seated ulceration, which sometimes follows the application of other acrid substances that have been used for the same purpose. The cantharides in powder is mixed with lard and wax, so as to form a plaster of a proper consistence, which is applied to the part, generally for 10 or 12 hours: at the end of that time, the proper vesicle is usually formed; it is then cut, to allow the serous fluid to be discharged, and the inflamed part is dressed with any mild ointment. Camphor has been sometimes add- ed to the blistering plaster, with the view of obviating the strangury which is liable to be occasioned. But it is very doubtful if it has any such effect: the plentiful 342 RUBEFACIENTS use of diluents, while the blister is applied, prevents it much more certainly; and it is always proper when a blister is applied, especially if large, or in inflammatory diseases, to order the patient to drink freely of any mild diluent liquor. Where the strangury does occur, from the application of a blister, it is relieved by an enema of tepid water, with a little of expressed oil, and 30 drops of tincture of opium. In some diseases, as in apoplexy, it is of importance to be certain of the operation of an epispastic, and to have its effect produced in a short time. To attain these, a compound plaster is ordered by the Edinburgh Col- lege, Emplast. Meloes Vesicat. Comp. in which the stimulating and epispastic power of the cantharides is increased by the addition of other acrid substances, burgundy pitch, turpentine, verdigrease, mustard and pepper. After a blister has been raised, it is often of advan- tage to convert the serous discharge into one of a pu- rulent nature, by exciting suppuration, or to form what is termed an Issue: this can easily be effected by the application of any acrid stimulating ointment; one com- posed of wax and oil, with a small proportion of can- tharides, is commonly used for this purpose, as by the irritation it excites, it keeps up the inflammation, and at length produces suppuration. Any foreign body re- tained on the inflamed part answers the same purpose. What are named Orange Peas, the small unripe fruit of the orange, polished, are usually employed, as by their odour they cover the foetor of the discharge. One of these is retained on the blistered part by a slip of adhesive plaster, and by the irritation it occasions keeps up a constant discharge. A seton, or cord introduced by means of a needle, answers the same purpose. When by any of these methods a puriform discharge is established in a part, considerable effects arise from the morbid action which it continues, and the evacua- tion it occasions. It is a practice often employed with AND EPISPASTICS. 343 advantage in asthma, paralysis, and a number of chro nic affections. Euphorbium. Euphorbia Officinalis. (Page 337.) This resinous substance, already considered as an errhine, is a powerful vesicatory. It enters into the epis- pastic compositions of the farrier, and might be employ- ed, mixed with other epispastics, when it is of import- ance to obtain the effects of a blister in their full ex- tent, speedily and with certainty. Pix Burgundica. Burgundy Pitch. Pinus Abies. Monacia. Mo- nadelph. Conifere. This resinous concrete is obtained by exudation from incisions made in the trunk of the tree. It is boil- ed with a small quantity of water; is strained; and when cold forms a concrete resinous matter, retaining a little essential oil. As a rubefacient, it is spread upon lea- ther, and applied to the skin: it excites a slight degree of inflammation, and an exudation of serous fluid, without entirely separating the cuticle, so as to produce a blister. Hence it is less painful in its operation, and the application of it can be continued for a considerable time. It is used with advantage in catarrh, pertussis and dyspnoea. Offic. Prep.—Emp. Pic. Burg. Dub. Sin apis. Mustard. (See page 256.)—The flour of mustard-st ed, mixed with an equal part of wheat-flour or crumbs of bread, and made into a paste with vine- gar, forms what is named a Sinapism, an application which acts as a powerful rubefacient. It is applied to the soles of the feet in typhoid fevers, where there is extreme debility, or determination to the head. It is used in the same manner in comatose affections; the application of it in either case being continued for an hour or two. It soon excites a sense of pain, and if ap- plied long produces inflammation. Offic. Prep.—Catap. Sinapeos. Lond. Dub. 344. RUBEFACIENTS, Sec. Allium. Garlic. (See p. 325.)—The bruised root of this plant, applied to the soles of the feet, produces effects similar to those of the sinapism, and is used for the same purpose. It is less powerful, and its odour is ungrateful. Ammonia. Ammonia. The solution of ammonia in water (Aq. Ammonias) is obtained by decomposing muriate of ammonia by lime, with the assistance of heat, the ammoniacal gas being absorbed by water, through which it is transmit- ted. The solution has a very pungent odour, and appli- ed to the skin acts as a rubefacient. The common form under which it has been employed, is mixed with two or three parts of expressed oil, with which it forms a thick saponaceous compound, formerly known by the name of Volatile Liniment. A piece of flannel moisten- ed with this, and applied to the skin, soon excites pain and superficial inflammation. It is often employed instead of a blister to the throat, in angina tonsillaris, being less painful, yet frequently effectual. It is also some- times applied by friction to relieve the pain of rheu- matism. Offic. Prep.—Ol Ammon. Ed. Dub. 345 THIRD DIVISION. OF CHEMICAL REMEDIES. * UNDER this division are comprised those few classes of medicines, the operation of which either depends entirely on the chemical changes they produce, or is materially modified by these changes. I have placed under it the classes of Refrigerants, Antacids, Lithon- triptics, and Escharotics. CHAPTER XVI. ' OF REFRIGERANTS. The substances arranged by authors on the Materia Medica under the appellation of Refrigerants, have been usually defined, such medicines as directly diminish the force of the circulation, and reduce the heat of the body without occasioning any diminution of sensibility or nervous energy. The theory delivered of the opera- tion of these medicines is unsatisfactory and obscure; nor are even the facts adduced to establish the existence of such a class of remedies altogether precise. It is acknowledged by Dr. Cullen, that " in many trials made on purpose, it did not appear that the supposed refrigerants diminished that temperature of the body, which is the ordinary temperature of it in health." He concludes, therefore, that the definition should apply only to the reduction of the temperature when it has been morbidly increased, and even in this case the effect Vol. I. 2 X 346 REFRIGERANTS. of these medicines is allowed by practical writers not to be considerable. It is not necessary to review the opinions that have been advanced on the mode of operation of these sub- stances, since they are in general absurd and unintelli- gible. Dr. Cullen, in particular, gives an explanation on this subject, founded on the most obscure and hy- pothetical ideas, and which, indeed, it is scarcely possi- ble to understand. Its basis, he remarks, is a doctrine delivered by Needham, " that there is every where in nature an expansive force and a resisting power; and that, particularly under a certain degree of heat, the ex- pansive power appears in all the parts of organized bo- dies, in consequence of which they show a singular vegetating power; while, at the same time, in other bo- dies there is a power resisting and preventing the action of this vegetating power, and at least of diminishing its force." This power, it is added, is found in those saline substances commonly supposed to be refrigerants; and, " as an increase of heat is no other than an increase of the expansive force in the heated parts, it may be un- derstood, how resisting powers may diminish any pre- ternatural expansive force and heat in our bodies." The discoveries of Modern Chemistry furnish some facts, which may perhaps be applied to this subject; and indeed it is only to those discoveries which es- tablish the source of animal temperature, that we are to look for an explanation of the changes to which it is subject. It is established by numerous experiments and ob- servations, that the consumption of oxygen in the lungs is materially influenced by the nature of the ingesta re- ceived into the stomach. When the food and drink are composed of substances which contain'a small propor- tion of oxygen, it is known that the consumption of oxygen m the lungs is increased, and this even in a short time after the aliment has been received. Thus Mr. Spalding, the celebrated diver, observed, that whenever he used a diet of animal food, or drunk spi- REFRIGERANTS. 347 ritous liquors, he consumed in a much shorter time the oxygen of the atmospheric air in his diving bell; and therefore he had learned from experience to confine himself to a vegetable diet, and water for drink, when following his profession. During digestion too, it was established by the experiments of Lavoisier and Se- guin, that a larger proportion of oxygen than usual is consumed. But it is known that the animal temperature is de- rived from the consumption of oxygen gas by respira- tion; and that an increase in that consumption will oc- casion a greater evolution of caloric in the system, and consequently an increase of temperature in the body, while a diminution in the consumption of oxygen will have an opposite effect. If, then, when the temperature of the body is mor- bidly increased, we introduce into the stomach sub- stances containing a large proportion of oxygen, espe- cially in a loose state of combination, we may succeed in reducing the general temperature. This we accom- plish in part by a vegetable diet, but still more effectu- ally by the free use of acids. The vegetable acids in particular, which by experience are found to be the best refrigerants, are readily acted on by the digestive powers, and assimilated with the food. And as the large quantity of oxygen they contain is already in a concrete state, little sensible heat can be produced by the com- bination of that element with the other principles of the food. The nutritious matter which is received into the blood, containing thus a larger proportion of oxygen than usual, will be disposed to abstract less of it from the air in the lungs, and consequently less caloric will be evolved. The temperature of the body will be re- duced, and this again operating as a reduction of sti- mulus, will lessen the number and force of the contrac- tions of the heart. It might be supposed, however, that any effect of this kind must be very trivial; and it actually is so; for we find in practice that refrigerants produce no sudden 348 REFRIGERANTS. or great change. They operate slowly, and have little other effect than moderating the morbidly increased temperature. The whole of their effects, as Dr. Cullen remarks, are so slowly produced, as not to be very evi- dent to our senses, nor easily subjected to experiment, being found only in consequence of frequent repeti- tion. This is probably the action of acids. The other re- frigerants, the neutral salts, perhaps act in a similar manner; the acid they contain may yield oxygen; but they are still less effectual than acids, and their refrige- rant power is even problematical, except in so far as they operate on a principle different from that which has been pointed out,—the power they have of produc- ing in the stomach a sensation of cold. If a draught of cold water be swallowed, the sensation of cold it pro- duces in the stomach is equivalent to a partial abstrac- tion of stimulus, which being extended by sympathy to the heart, occasions a transient reduction in the force of the circulation, and by this, or by a similar sympa- thetic affection, causes a sensation of cold over the body. Nitre is an example perhaps of a refrigerant act- ing in this manner. It excites a sensation of cold in the stomach, even when taken dissolved, and still more in the solid state; and this is quickly followed by a re- duction in the number and force of the pulsations. Hence nitre acts more suddenly than any of the other refrigerants, and is more transient in its operation. It may also, however, operate in some degree more per- manently, in the same manner as the vegetable acids; as it appears that nitre, from the florid colour which it gives to blood, parts with oxygen readily It is evident that the indication to be fulfilled in the treatment of disease by the use of refrigerants, is the reduction of the morbidly increased temperature. Hence the propriety of their administration in svnocha and other pure inflammatory diseases, and in typhus fever; in both of which the temperature of the body is increased, though from different causes. In inflamma- REFRIGERANTS. 349 tory diseases, the circulation being so much more ra- pid than usual, a greater quantity of blood is sent both through the whole body and through the lungs in a given time; and the usual alterations of the blood going on, the evolution of caloric, which is the consequence of these alterations, must be increased, and the tempe- rature raised. In such cases, the use of acids, by lessen- ing the disposition of the blood to consume oxygen in the lungs, may be useful in reducing the temperature; and nitre may be of advantage, as it diminishes the force of the contractions of the heart; but these means, it is evident, can have only a trivial effect, compared with those direct evacuations by which the force of the circulation is lessened. The increased temperature in typhus fever cannot be ascribed to the same cause, but seems rather owing to the absorption of the animal solids constantly going od, and which, containing comparatively little oxygen, cause the blood to consume more of it in the lungs. The in- troduction of acids into the system, by affording this element in a concrete state to that matter, will lessen the consumption of it in the lungs, and will of course moderate the morbidly increased temperature. In either of these forms of disease, therefore, refrigerants may be useful, and accordingly we find them very generally used m all the species o( febrile affection; though they are still to be regarded as medicines of weak power. 350 REFRIGERANTS. Citrus medica. Citrus aurantium. Tamarindus indica. AcETUM. Super-tartras potass.*. NlTRAS POTASSJE. Boras sodje. All acids are supposed to be Refrigerants; but the vegetable acids are allowed to possess this power in a more eminent degree,—a superiority which, according to the preceding view, must be founded on their being more easy of assimilation, and of being acted on by the chemical processes of the living system. The native vegetable acids are found chiefly in the fruits of vegetables. The sour juice of these fruits con- sists of the Citric or Malic Acid, or more frequently of a n.ixture of both, sometimes with the addition of tar- taric acid. The citric acid is that which is most largely employed, as it forms chiefly the acid juice of the orange and lemon, the two acid fruits in common medicinal use. Citrus Medica. Lemonum. Lemon. (Page 203.) Succus fruc- tus. Acidum Concretum. Tee juice of the fruit of the lemon consists almost entirely of citric acid, diluted with a portion of saccha- rine and mucilaginous or gelatinous matter. As the fruit cannot always be procured, various methods have been employed to preserve the juice. The most effec- tual is to add to the expressed juice a portion of alko- hol, and to put it aside until the mucilaginous matter is deposited, then by a moderate heat to evaporate the al- REFRIGERANTS. 351 kohol, and preserve the acid juice in bottles carefully closed. Even as prepared in this method, however, the juice is liable to chemical change. By a different process, the citric acid can be procured pure and in a crystallized state. To the expressed le- mon juice gently heated, carbonate of lime is added so as to neutralize it; citrate of lime is formed, and being insoluble is precipitated; it is washed with water to carry off the extractive and mucilaginous matter, and is then submitted to the action of sulphuric acid; which, when digested or boiled on it for a short time, com- bines with the lime, and disengages the citric acid; and by evaporation and cooling, this is obtained in a crystallized form. This process was originally given by Scheele, and it has been received into the London Pharmacopoeia. Lemon juice may be regarded as the principal refri- gerant, being adapted to cool and quench thirst, and used for these purposes in febrile affections. A grateful beverage is formed from it, diluted largely with water, and sweetened a little with sugar: or the fruit sliced down is added to any mild diluent. A preparation from it, which is used as a refrigerant in fever, is what is named the Saline Mixture, formed by neutralizing le- mon juice by the addition of a sufficient quantity of carbonate of potash, adding to this, water with a little sugar and a small portion of any distilled water. Of this mixture, a table-spoonful is taken occasionally; it is grateful, but cannot be considered as possessed of any power, any refrigerant quality which may belong to the acid being probably lost by its neutralization. Another form under which lemon juice is used in fever, principally with the view of relieving nausea or checking vomiting, is that of the Effervescing Draught, as it has been named. A solution of carbonate of pot- ash, and diluted lemon juice are mingled together, and while in the act of effervescence, the mixture is swal- lowed. The efficacy of it is probably dependent on the pungency and stimulant operation of the carbonic acid, 352 REFRIGERANTS. but it affords a grateful form under which this can be administered. The juice of the lemon, and indeed the citric acid, as it exists in any vegetable fruit, has been long known as nearly an infallible remedy in scurvy: a theory of its operation in removing this disease has been given, founded on its chemical agency, and particularly on the supposition that it imparts oxygen to the system, but which cannot be regarded as established. Lemon juice was employed as a remedy in syphilis, at the time nitric acid received a trial, and cases were given in which it proved successful. These, however, are doubtful, and it has never been established in prac- tice. The crystallized citric acid may be supposed to have the same power as the native lemon juice. This, how- ever, is somewhat uncertain, especially with regard to the treatment of scurvy, the disease in which the me- dicinal agency of this acid is most important. It is also deprived of the agreeable flavour of the lemon juice, and is hence even a less grateful refrigerant in fever, though this may be communicated to it, to a certain extent, by infusing a little of the rind of the lemon in the water in which it is dissolved. It is used medici- nally, principally in forming the effervescing draught, its solution being added to the solution of carbonate of potash. One ounce of it, dissolved in a pint of water, is said, by Dr. Powell, to be equal in strength to one pint of common lemon juice. Citrus aurantium. The Orange. Succus fructus. (Page 202.) The juice of the orange has a certain degree of sour- ness, accompanied in the variety named the China Orange, when ripe, with a sweetness; in that named the Seville Orange, with slight bitterness. The former is used as a refrigerant in febrile affections, more grateful, but less powerful than the fruit of the lemon. It is also used as a remedy in scurvy. REFRIGERANTS. 353 Tamarindus indica. Tamarind. (Page 266.) The fruit of the tamarind contains an acid pulp, which is preserved by the addition of a quantity of un- refined sugar, this forming the Tamarinds of the shops. The acid is principally the citric, sixteen ounces oi the prepared pulp containing, according to Vauquelin's analysis, an ounce and a half of citric acid, half an ounce of super tartrate of potash, two drachms of tar- taric acid, and half a drachm of malic acid. This pulp forms a grateful refrigerant beverage, a little of it being infused in tepid water, which is often taken in febrile affections. Acetum. Vinegar. Acidum Aceticum Dilutum. Vinegar is a weak acid, formed by that species of fermentation which succeeds to the vinous fermenta- tion, when the fermented liquor is exposed to the air with a due degree of temperature. During this expo- sure, its spiritous flavour and pungency, and its intoxi- cating quality, are lost, and it becomes more or less. sour. While this state of fermentation, denominated the Acetous, proceeds, the oxygen of the air is absorb- ed; according to the experiments of Saussure, carbonic acid is also formed; and the formation of the acid ap- pears therefore to be owing to these changes of com- position, in the principles peculiar to the vinous fer- mented liquor. The product differs according to the kind of fermented liquor from which it has been obtained. In general it is more acid as this has been more spiritous. Vinegar, from wine, therefore, is strongest, and its odour too is more grateful. It is obtained of inferior quality from fermented malt liquors, or from a solution of sugar. Vinegar when fully fermented is limpid, of a yellow- ish colour, has an odour which is agreeable and some- what pungent, and a sour taste. The acid existing in it is very largely diluted with water, and there are also present portions of gluten, mucilage and extractive matter, and frequently malic and tartaric acids. Vol. I. % Y 354 REFRIGERANTS. It is freed from these latter substances by distilla- tion; the process for which has a place in the pharma- copoeias. The distilled vinegar is colourless, but its odour is less grateful than that of common vinegar. It is however purer, and is not liable to decomposition, or to become mouldy; hence it is preferable for the pre- paration of medicated vinegars, and for other purposes in pharmacy. The acid which is the basis of vinegar, can be ob- tained in a concentrated state by various methods, prin- cipally by the decomposition of its saline combinations; and processes of this kind are now received into the pharmacopoeias. As obtained from the metallic acetates by heat, it is in particular extremely strong and pun- gent; and at one time, the acid thus procured was sup- posed to differ in composition from that obtained by other methods, and was distinguished by the appella- tion of acetic acid, while the other was named acetous. It has been established, however, that they differ only in the degree of concentration, and the name acetic is applied to the acid in all its states. When concentrated it is highly odorous and pungent, and is used princi- pally as a stimulating perfume. Common vinegar is sometimes employed as a refrige- rant in febrile affections. It is also much celebrated as an antidote to the vegetable narcotics. Externally, it is used as an application to burns, and as a discutient. In pharmacy, distilled vinegar is employed as the solvent of the active matter of several vegetable substances. Offic. Prep___Acid. Acet. Dist. Acid. Acet. Arom. Acid. Acet. Camph. Syr. Acid. Acet. Ed. Super-tartras potassje. Super-Tartrate of Potash. (Page 279.) From the excess of acid which this salt contains, it possesses the virtues of a refrigerant. A solution of it in a large quantity of water, sweetened with sugar, and re- ceiving flavour from the infusion of a small quantity of the rind of lemon, forms a cooling beverage, used in febrile affections, and recommended, especially in hos- REFRIGERANTS. 355 pital practice, by its cheapness. Its only disadvantage is its being liable to prove purgative. Nitras potass*. Nitrate of Potash. Nitre. (Page 294.) This salt impresses a sense of coolness in the mouth, and when taken in small doses frequently repeated, ap- pears to have the effect of reducing the force of the cir- culation. It is hence not unfrequently used as a refrige- rant in acute inflammatory diseases. It is given in a dose of from 5 to 15 grains repeated every four or five hours. When given in larger doses, it occasions nausea, and pain of the stomach. It is often also used as a refrigerant, under the form of gargle, in the different species of cy- nanche, one drachm being dissolved in six or eight ounces of water: or the nitre troches are allowed to dis- solve slowly in the mouth. Offic. Prep.—Troch. Nitr. Pot. Ph. Ed. Sub-boras sod*. Sub-Borate of Soda. Borax. This salt, consisting of boracic acid, united with soda, the soda being slightly in excess, is brought from Thi- bet, where it is found in a native state. It is purified in Europe by crystallization, and is usually in the form of crystalline masses of no regular figure; its taste is cool; it is soluble in eighteen parts of cold, and six of hot water. Borax is not used internally in modern practice, nor does it appear to possess any activity. Its solution is in common use as a cooling gargle; and mixed with an equal part of sugar, it is used in the form of powder to remove the aphthous crust from the tongue in children. Mixed with honey, it forms an officinal preparation in the London Pharmacopoeia, applied to the same pur- pose. Offic. Prep.—-Mel. Boracis. Ph. Lond. 356 CHAPTER XVII. OF ANTACIDS. These are remedies which obviate acidity in the stomach, by combining with the acid and neutralizing it. The substances most powerful in exerting this kind of action, and which can be employed, are the alkalies, and among the earths magnesia and lime. They can be regarded only as palliatives, the production of the acid being to be prevented by the administration of remedies capable of restoring the tone of the stomach. They are employed in dyspepsia, and in diarrhoea arising from acidity. ANTACIDS. Potassa. Soda. Ammonia. Calx. Magnesia. Potassa. Potash. This alkali is obtained from the incineration of the woody parts of vegetables. The ashes are lixiviated, and by evaporation the saline matter, consisting chiefly of sub-carbonate of potash, is procured. This forms the potash of commerce; it is purified by a second solution in water and evaporation; and to procure the alkali, lime is added to the solution of this sub-carbonate; the whole is put upon a nitre, so that the alkaline solution may pass slowly through the mass of lime; the carbonic acid is thus more effectually abstracted by the lime, and the ANTACIDS. 357 potash passes through in solution, sufficiently pure for any medicinal application. This solution (Aq. Potassa?) is sometimes employed to relieve the symptoms from acidity, where the generation of acid is constant and abundant, being given in a dose of 15 drops diluted in water. Its acrimony renders it, however, an unpleasant remedy. The sub-carbonate, or the neutral carbonate, is likewise occasionally employed in solution. But the most common form under which the alkali is used as an antacid, is the super-carbonate. For the preparation of this, a formula is introduced into the Edinburgh Pharmacopoeia, an ounce of sub-carbonate of potash being dissolved in ten pounds of water, and this being combined by a moderate degree of pressure, with an ex- cess of carbonic acid. By this impregnation, the acrid ajkaline taste is concealed, and an agreeable pungency communicated. The liquor is taken as an antacid, in the dose of half a pound occasionally. Soda. Soda. This alkali is obtained in the state of carbonate, from the saline matter, formed in the combustion of marine vegetables, the barilla of commerce. In its pure state it is not employed in medicine; the carbonate or sub-car- bonate is used as a lithontriptic, rarely as an antacid; but the super-carbonate is frequently taken. It is pre- pared in the same manner as the super-carbonate of potash, the proportions being so adjusted that the strength of each solution i^nearly the same. It is there- fore taken in the same dose, and is usually preferred, as being supposed to be more mild, to the super-carbonate of potash water. Ammonia. Ammonia. The solution of ammonia in water (Aq. Ammoniae) is sometimes used as an antacid, and it has been recom- mended by Dr. Sims as superior even to the other alkalis in relieving cardialgia, and other symptoms from acidity: so much so, that he has been led to suppose 358 ANTACIDS. that these symptoms frequently arise, not merely from the liquid contents of the stomach being acid, but from the elastic fluid with which it is more or less distended having a degree of acidity, on which the ammonia from its volatility more readily acts. From 20 to 30 drops of the solution are given in a cupful of water. The solu- tion of the carbonate of ammonia is also used in a dose of half a drachm; and the aromatic ammoniated alkohol forms a still more grateful antacid and stimulant. Calx. Lime. (Page 183.) Lime, under the form of lime water, is occasionally used as an antacid, in a dose of four or six ounces. It operates, not only chemically, neutralizing the acid, but by its astringent and tonic power contributes to restore the tone of the stomach. It is also employed under the form of carbonate of lime, of which there are two varie- ties in use, Creta Alba, and Lapilli Cancrorum: the former named by the Edinburgh College Carbonas Calcis Mollior, and the latter, Carbonas Calcis Durior. Carbonas caixis mollior. Crcta Alba. White Chalk. This is a carbonate of lime, found abundantly in na- ture, nearly pure, or containing only minute quantities of other earths. From the grosser impurities with which it is mixed, it is freed by levigation and washing. It is then named Prepared Chalk, (Creta Prreparata.) This is an antacid in very common use. As the compound it forms with the acid in the stomach has no purgative quality, but appears to be quite inert, it is the antacid commonly employed to check diarrhoea proceeding from acidity. It is given in a dose of one or two drachms, with the addition of a small quantity of any aromatic. The chalk mixture of the Edinburgh Pharmacopoeia affords a very good form for administering it. Offic. Prep.—Pulv. Carb. Calc. Comp. Mist. Carb. Calc. Ph. Ed. Lond.—Pulv. Cret. C. et Opio. Ph. Lond. —Trocfc. Carb. Calc. Ed. ANTACIDS, 359 Carbonas calcis durior. Cancrorum Lapilli et Chelae. Crabs' Stones, Crabs' Claws. Cancer Astacus. Cancer Pagunis. In the head and stomach of the river craw-fish, are found certain concretions, consisting principally of car- bonate of lime, with a little phosphate of lime and ani- mal gelatin. They are prepared by levigation, and washing with water, and are named Lapilli Cancrorum praeparati, formerly Oculi Cancrorum praeparati. The tips of the claws of the common sea-crab are similar in composition, and are prepared in the same manner. They are named Chelae Cancrorum praeparatae. Both are employed as carbonates of lime, and being prepared with more care are in general smoother, and more easily diffused in water than the common prepared chalk, though there is reason to believe, that as met with in the shops, they are merely chalk with a little gelatin. Magnesia. Magnesia. (Page 269.) Magnesia is a primary earth, usually obtained in the state of carbonate by decomposing its sulphate or its muriate by an alkaline carbonate, and in its pure state, by expelling from this the carbonic acid by the application of heat. In either state it is used as an anta- cid: the carbonate has the inconvenience, where large quantities of it require to be taken, of occasioning flatu- lence from the disengagement of its carbonic acid, and this leads to the preference of the pure magnesia. It is given in a dose of a scruple or half a drachm. The salt which magnesia forms with the acid in the stomach proves slightly purgative; and this is the only reason for distinction in practice between this earth and the carbonate of lime, the one being used where diarrhoea accompanies acidity; the other where a laxative effect is wished to be obtained. 360 CHAPTER XVIII. OF LITHONTRIPTICS. Lithontriptics are medicines supposed to have the power of dissolving urinary calculi: their operation, it is obvious, must be purely chemical. The alkalis, it has been long known, relieve the pain- ful symptoms arising from these calculi; and it was found by experiment that they are capable of dissolving these concretions out of the body; hence it was conclu- ded, not unjustly, that their efficacy depends on their solvent power. The discoveries of Modern Chemistry have thrown farther light on this subject: it has been proved that these urinary concretions consist frequently of a pecu- liar animal acid, the lithic or uric acid, either nearly pure, or sometimes combined with ammonia, and ani- mal matter, apparently albumen. With this acid, the alkalis, in their pure state, are capable of combining, forming a compound soluble in water. It has been ascertained, that from the internal admi- nistration of the fixed alkalis, either potash or soda, the urine becomes impregnated with them, so as to be sensibly alkaline. Experiments too have proved that either of these alkalis may be given to such an extent, as to enable the urine applied to a calculus out of the body to dissolve part of it; and it appears therefore to follow, that the same solvent power will be exerted on a concretion in the bladder or kidney. Unfortunately, however, the use of the alkalis to this extent cannot long be persisted in, from the irritation they occasion in the stomach and the bladder; and we have scarcely, perhaps, any decisive proof of a urinary calculus of any considerable size being actually dissolved. The use of these agents in a moderate quantity, however, LITHONTRIPTICS. 361 may prevent its increase; and, as it is often at length covered by matter deposited from the urine, by which its surface is rendered more smooth, this practice fre- quently alleviates the symptoms. When the alkalis are used in this manner merely as palliatives, they are generally employed in the form of carbonate, or super-carbonate, as in that state they are more mild and pleasant. Their solvent power is how- ever thus impaired. Still the alkalis in this mild form retain the power of preventing the increase of the uri- nary concretion. The deposition of uric acid, to which that increase is owing, depends in a great measure on the generation of acidity in the primae viae. The acid which is there formed passes off by the kidneys, and causes the precipitation of the uric acid; the use of the mild alkalis, by correcting this acidity, prevents this drposition, and of course prevents the increase of the urinary concretion, and lessens the irritating quality of the urine. It has accordingly been found, that under a course of alkaline remedies, the deposition of uric acid, so frequently abundant from the urine of those who are liable to calculus, diminishes rapidly. The administration, then, of these substances is dif- ferent, according to the object of the practitioner. If he attempt the solution of the calculus, the pure alkali must be given in as large doses, and for as long a time as the patient can bear it: if he seek merely to palliate the symptoms, the continued use of moderate doses of the alkali saturated, or super-saturated with carbonic acid is sufficient, and is even preferable, as less hurtful to the stomach or general system. In both cases, it is proper that diluents should be freely used; and the pure alkali, when employed, ought always to be mixed with some mucilaginous or gelatinous fluid. These were the views generally given of the opera- tion of lithontriptic medicines, after the discoveries of Scheele and Bergman had made known the properties of uric acid. More recent investigations have still far- ther extended our knowledge of this subject, and un- Vol. I. 2 Z 362 LITHONTRIPTICS. fortunately preclude still more the hope of lithontriptics being employed with advantage as actual solvents. It had always been known, that urinary calculi are not of uniform appearance and qualities. Dr. Wollas- ton's researches have proved, that they are of very dif- ferent chemical constitution, and his experiments have been confirmed by those of Fourcroy and Vauquelin. Besides the uric acid calculus, which is generally of a brown or yellowish colour, of a compact or radiated structure, smooth on the surface, and perfectly soluble in alkaline solutions, another had been observed, com- posed principally of a matter frequently disposed in layers, white, of a lamellated structure, soft and smooth to the touch, and giving a light powder of a brilliant whiteness. This calculus is not soluble in alkaline so- lutions, but dissolves very easily in diluted acids: it melts before the blowpipe into an enamel; the substance composing it is phosphate of magnesia and ammonia, and though it seldom forms an entire calculus in its pure state, it is often intermixed with the other usual ingredients, or disposed with these in alternate layers. Phosphate of lime forms another variety of calculus, sometimes alone, but more generally mixed with uric acid, or with phosphate of magnesia and ammonia. Calculi of this kind have usually no great induration, feel dry and rough, and without any lamellated or spathose structure; they are not dissolved by the alka- lis, but are soluble more or less in diluted acids. Lastly, a calculus had been known to surgeons, un- der the name of Mulberry Calculus, derived from its purplish colour, and its rough irregular surface. This is composed principally of oxalate of lime, with por- tions of uric acid, phosphate of lime, and animal mat- ter. It is harder and heavier than any of the others; and is less affected by the usual solvents, alkaline solu- tions having no effect upon it, and acids dissolving it with great difficulty; the alkaline carbonates slowly de- compose it. Now, from these diversities, in chemical constitution, LITHONTRIPTICS. 363 among urinary concretions, it is obvious, that we cannot expect uniform advantage from the use of any active solvent as a lithontriptic, since what dissolves one cal- culus will have no effect upon another; and cases have accordingly occurred, where, instead of relief being obtained, as it frequently is from the use of alkalis, it was obtained from weak acids. There is also a peculiar source of difficulty, which has been pointed out by Mr. Brande, attending the attempt to exhibit lithontriptics as solvents, which must probably render it impracti- cable. The phosphates of lime and magnesia, which exist in the urine, are retained in solution principally by its excess of acid: if, therefore, with the view of dissolving a uric acid calculus, or preventing its increase, alkalis be given so as to neutralize this acid, the depo- sition of these phosphates may be favoured, and a layer of them form on the existing calculus. And there is reason to believe, that the softness and sponginess which have been observed not unfrequently on the surface of calculi, in patients who have continued for a long period the use of alkalis, and which have been regarded as proofs of at least partial solution, have arisen from a deposition of this kind. If, on the other hand, from the state of the urine, or from the information afforded by a small calculus being discharged, there were reason to believe that a calculus in the bladder consisted chiefly of phosphate of ammonia and magnesia, if we attempted the solution of this, by the administration of weak acids, we run the hazard of causing the deposition of uric acid. Nor can we hope, by an alternate use of acids and alkalis, so to adjust them as to obtain to any extent their solvent effects, without these counteracting results. There is another mode, in which it has been sup- posed that lithontriptics may exert a solvent power. In all urinary calculi, there exists a quantity of animal mat- ter, supposed to be of the nature of albumen, and which has also been regarded as the cementing ingredient, giving induration to the calculus. On this it has been conceived solvents may act, so as to destroy the cohesion 364 LITHONTRIPTICS. of the aggregrate. The experiments of Dr. Egan con- firm this, he having found that lime water is more effectual in destroying the cohesion of a urinary calculus, than an alkaline solution,—a result which, on repeating his ex- periments, I have likewise obtained. Now this supe- riority cannot be ascribed to any action of th<- lime on the saline ingredients of the calculus, but must arise rather from its chemical action on the albumen or animal mucus, of which it is known to be the solvent; and i? may therefore be supposed that lime water, from this opera- tion, might be used with advantage as a lithontriptic. It would of course require to be given in combination with alkalis, the latter neutralizing the excess of acid in the urine, which would otherwise combine with the lime, and render it inert. But it may be doubted, if this could be managed, so as to obtain any important effect; or that lime could be secreted in its pure form by the kidneys. From these observations, the advantages to be ex- pected from lithontriptics, it is obvious, must be very limited. They probably cannot be given with greater benefit than simply to correct the excess of acidity in the urine, so frequent in those who labour under calcu- lus, and thus render it less irritating, and prevent the increase in the size of a concretion. Or, it is possible, in cases of the mulberry calculus, which produces much pain from its rough and pointed surface, that pushing the use of them a little farther might prove useful, even by giving rise to the formation of a layer of the phos- phate of ammonia and magnesia, which would at least render the surface of the calculus soft and smooth. In their administration, it may be of advantage to attend to the state of the urine, so far as regards its chemical con- stitution, and to suspend or vary the remedies as this may change. And in all cases the continuance of the remedies, and the length to which they are carried, ought to be regulated principally by the relief from pain 'which the patient receives. 365 LITHONTRIPTICS. Potassa. Soda. Sapo albus. Calx. Potassa. Potash. (Page 356.) This alkali is used as a lithontriptic, either pure or combined with carbonic acid. The pure alkali in the state of solution (Aq. Potassae) has been given in a dose of 15 or 20 drops morning and evening, increasing this gradually as far as the stomach can bear it, until the U'ine is rendered alkaline; and at the same time dimi- nishing the irritation it is liable to produce, by the free use of diluents, and of any mucilaginous or gelatinous liquid. The action of the pure alkali being more power- ful than that of the carbonate on uric acid calculi, it is under this form that it has been employed when the ac- tual solution of the calculus has been attempted. Inde- pendent, however, of the difficulties which attend this, from the circumstances pointed out under the general observations on the action of lithontriptics, it is scarcely possible to continue the use of the pure alkali to the re- quisite extent, from the irritation it occasions both in the stomach and bladder; and when it is to be used as a palliative, it is better to employ it under the form of the super-carbonate. The super-carbonated potash water, already noticed, (page 356.), affords the most effectual palliative in cases of urinary calculi; the relief obtained from its appears to arise from its neutralizing the free acid in the urine, and thus rendering it less irritable. From half a pound to a 366 LITHONTRIPTICS. pound is taken in the course of the day; and it has the important advantage, that, from its mildness, it can be continued for any length of time without reluctance. Soda. Soda. (Page 357.) Soda, like potash, is used as a lithontriptic, seldom, however, in its pure form. The carbonate, or rather sub- carbonate, is obtained from the barilla of commerce by solution in water and crystallization. The crystals con- tain half their weight of water of crystallization, and are soluble in two parts of cold, and in an equal part of boiling water. This crystallized salt affords a very ex- cellent form under which it may be administered, so as to give at least the advantages of a palliative, and which is less expensive than any other. It is what has been named the Soda Pill. The crystals are exposed to a very gentle heat, until they lose their water of crystallization, and the dry powder is made into pills with soap. Of these, half a drachm or a drachm are taken in the course of the day. Soda is likewise employed under the form of the su- per-carbonated soda water, the powers of which are simi- lar to those of the super-carbonated potash water, and which is taken in the same manner. Sapo albus.—Soap is a form under which the fixed alkalies have been administered in calculous affections. It is a chemical combination of expressed oil with potash, or soda. Potash forms only a soft soap, soda gives one that becomes hard; and to form the purer soap it is com- bined with the mildest vegetable expressed oil. The soap is white, but sometimes is designedly coloured by the addition to it, while soft, of a solution of sulphate of iron. The acrimony of the alkali is much diminished by its combination with the oil, and on this account soap has been preferred as a lithontriptic, one or two ounces being taken in the course of the day. From the oil it contains, however, it is nauseous, and in such large doses gene- LITHONTRIPTICS. 367 rally offensive to the stomach, and the super-saturation with carbonic acid affords a much better method of ren- dering the alkali mild. Calx. Lime. (Page 183.) Lime, in the form of lime-water, has been used in calculus, in the quantity of a quart or more daily: it may prove useful by correcting acidity; but in the small quan- tity in which it can be taken, it can scarcely be supposed that any of it will be secreted by the kidneys, so as to change the composition of the urine. Were it secreted, indeed, it would be rendered insoluble by the free phos- phoric and uric acids. The only method in which it could be brought to act on a calculus, would be by con- joining its administration with that of the alkalis, so that the urine should be rendered alkaline. This com- bination constituted the celebrated remedies of Stephens; but even with every precaution it may be doubted if the lime could be made to exert any real lithontriptic power. Bitters and astringents have been found of service in calculous cases, evidently by restoring the tone of the stomach, and thus preventing the generation of acid* But they cannot be considered as Lithontriptics. CHAPTER XIX. OF ESCHAROTICS. Escharotics are substances which erode or dis- solve the animal solids. They produce erosion or ulcera- tion, either by directly combining with the animal mat- ter, and forming a soft pulp, or a species of eschar: or they sometimes appear to act by a resulting affinity, causing the elements of the soft solids to enter into new 368 ESCHAROTICS. combinations, whence their cohesion is subverted, and their composition changed. In both cases the life of the part is destroyed. They are employed principally to re- move excrescences, to establish an ulcer, or to change the surface of an ulcerated part, converting it into a sim- ple sore. The action of all of them is purely chemical. ESCHAROTICS. AciDA MINERALIA. Super-sulphas aluminjE et potassa. Potassa. NlTRAS AROENTI. murias antimonii. Sulphas cupri. Acetas cupri. Murias hydrargyri. sub-nitras hydrargyri". Oxidum arsenici album. juniperus sabina. The Mineral Acids act rapidly as escharotics, especially the sulphuric and nitric acid; but from their fluidity they can seldom be conveniently applied. Super-sulphas alumin-e et potassae. Alumen. Alum. Alum, from its excess of acid, has a degree of escha- rotic power; and under the form of dried alum, in which its water of crystallization is expelled, is sometimes used in fine powder to check the growth of fungous ex- crescences from ulcers. This powder, rubbed with a little sugar, is, from the same property, applied to re- move opaque specks from the cornea. Potassa. Potash. (Page 365.) Pure potash, in its solid state, forms a powerful escharotic, which has long been in use under the name ESCHAROTICS. 369 ©f Causticum Commune Acerrimum. When its solu- tion, before being evaporated entirely to dryness, is mixed with a portion of lime, its operation is rendered rather weaker: this preparation is named Causticum Commune Mitius. Either of them is made into a paste with soap, and applied to the part. This application is frequently employed to establish an ulcer, and some- times in preference to incision to open a tumor: it is at- tended with a considerable degree of pain, and a sense of burning heat; after it is removed, a cataplasm is ap- plied, by which this is relieved, and suppuration esta- blished. Mr. Simmons has recommended potash in preference to other escharotics, to prevent the effects from the bite of a rabid animal; it is applied freely to the bitten part; and the preventive operation of excision, he has supposed, may be rendered more certain by touching the surface with potash. Nitras argenti. Nitrate of Silver. Causticum Lunare. Lunar , Caustic. This preparation is obtained by dissolving silver in nitric acid, evaporating the solution to dryness, melting the mass by a gentle heat, and while liquid running it into cylindrical moulds, in which, as it cools, it becomes concrete. It is the caustic which is in most common use for checking the growth of fungous excrescences, or changing the diseased surface of an ulcer, a little of it being dissolved in as small a portion of water as is suf- ficient, and applied by a pencil to the part. Murias antimonii. Muriate of Antimony. (Page 251.) This preparation of antimony has been used as an escharotic, but being liquid it is not easily confined to the part on which it is designed to act, and it has no par- ticular advantage to recommend it. Sulphas cupri. Sulphate of Copper. Vitriolum Coeruleum. Blue Vitriol. This salt is a mild escharotic, and from this mildness •f its operation is adapted to particular cases. Its solu- Vol. I. 3 A 370 ESCHAROTICS. tion in water is sometimes employed to change the dis- eased surface of sores, especially of venereal sores, and either in solution, or in powder mixed with any mild vegetable powder, it is applied to remove specks on the cornea. Sub-acetas cupri. Sub-acetate of Copper. jErugo JLris. Verdigrease. This preparation is formed by stratifying plates of copper with the husks of the grape. These suffer a slow fermentation, whence vinegar is formed; and this acting on the copper, forms a green oxide, with which a por- tion of the acid likewise combines, so as to form a sub- acetate. It is in frequent use as an escharotic, principally to change the surface of foul ulcers, being applied under the form of ointment mixed with lard. In the same form, it is applied as a stimulant in some kinds of oph- thalmia. Offic. Prep.—Ungt. Sub-acet. Cupr. Ph. Ed. Dub. —Oxymel iEruginis. Dub. Lond. Murias hydrargyri corrosivus. Corrosive Muriate of Mercury. This preparation of mercury is occasionally employ- ed as an escharotic. Its solution in water, in the propor- tion of one grain to the ounce, is in particular applied to venereal ulcers. And still more dilute, it is sometimes used as a lotion to herpetic eruptions. Sub-nitras hydrargyri. Sub-nitrate of Mercury. This is in common use as an escharotic, and as a stimulant application to foul and languid ulcers. Re- duced to fine powder, it is sprinkled on the part, or it is applied mixed with lard in the form of ointment; for the preparation of which, a formula is given the Phar- macopoeias. Offic Prep.—Ung. Sub-nitr. Hydrargyr. Ph. Dub. Lond. Ed, ESCHAROTICS. 371 Oxidum arsenici album. Oxide of Arsenic. (Page 180.) White oxide of arsenic has been frequently employ. ed as an external application to cancer, and though it has been regarded as in some measure specific, its im- mediate action is that of an escharotic. It was first intro- duced as an empirical remedy, and was applied, mixed with several vegetable powders, and made into a paste with the yolk of an egg: this, in a few hours, formed an eschar, by which the diseased surface was changed; and by exciting suppuration by the application of cataplasms, this was thrown off. It has since been used under the form of ointment or solution. The latter has been sup- posed the least painful form, though perhaps it is not the most effectual. Ten grains are dissolved in one ounce of water, and this solution is applied by a pencil to the sore. It not unfrequently amends the discharge, causes the sore to contract in size, and eases have even been related of its having effected a cure. Violent lanci- nating pain is sometimes produced by its application; and in some cases, from its continuance, the general system appears to be affected; a symptomatic cough being induced, which cannot be relieved but by sus- pending the application, and when this does come on, the use of the arsenic ought to be stopt. It requires, therefore, to be used with caution. Juniperus sabina. Savine. (See p. 287.) The leaves of savine possess an acrid power, whence they are empjoyed as escharotic. The powder sprinkled on warts or excrescences removes them; or made into an ointment with lard, is used as an application to old ulcers, and to some obstinate cutaneous affections: it has also been recommended as superior to any other stimulating application in exciting that degree of suppu- ration, necessary to keep up a discharge from an issue. Offic. Prep.—Cerat. Sabinae, Ph. Lond. Dub.—Ol. Sabinae, Ph. Ed. Dub. 372 FOURTH DIVISION. OF MECHANICAL REMEDIES. THE last subdivision of the classification includes those classes of remedies, the operation of which is merely mechanical. Under this I have placed Anthel- mintics, Demulcents, Diluents, and Emollients. They are classes of comparatively little importance. CHAPTER XX. OF ANTHELMINTICS. Anthelmintics are remedies which expel worms from the intestinal canal. They have been supposed to produce this effect by various modes of operation, prin- cipally, however, mechanical. Some, which are in coarse rough particles, as iron or tin-filings, or consist of sharp spiculae, as the down of the dolichos pruriens, are supposed, by the mechanical action of these, to dislodge from the mucus of the intes- tine» the worms which are evacuated. Other substances ranked as anthelmintics seem to have no other property than bitterness. By this quality they have been supposed to prove noxious to these animals: it has also been imagined, that these, so far as they prove useful, do so by restoring the tone of the digestive organs; the production of worms being sup- posed to proceed from debility of these organs, in con- sequence of which, either the food is not properly assi- ANTHELMINTICS. 373 milated, or the secreted fluids poured into the intestines are not properly prepared. Lastly, other remedies of this class apparently ope- rate by their cathartic power. Those cathartics" which discharge the mucus of the intestines, as gamboge, scammony, or calomel, are supposed more peculiarly to have this effect: and perhaps it is this sub-division of anthelmintics that have most efficacy. Some anthel- mintics, it is observed by Dr. Hamilton, " have beeiv considered as specific poison to the insect, and others are conceived to destroy it by mechanical triture. Most of them have had their partisans for the day, and have passed in succession through the ordeal of expe- ' rience into oblivion. The utility of such anthelmintics as have been found to be most beneficial, has, in my opinion, been in proportion to the purgative powers which they possessed " After a course of those anthelmintics, which are not directly cathartic, it is usual to give a full dose of a pur- gative, which is even repeated two or three times, and to this a considerable share of the effect, when worms are evacuated, is probably to be ascribed. Calomel, with jalap, gamboge, or scammony, is the cathartic usually employed. 374 ANTHELMINTICS. dolichos fruriens; Ferri limatura. Stannum pulveratum. Olea europjsa. Artemisia santonica. Spigelia marilandica. Poltpodium yiLix mas. Tanacetum vulgare. Geoffr.ea inermis. Cambogia gutta. Sub-murias hydrargyri mitis. Dolichos pruriens. Cowhage. Diadelph. Decand. Papilionacee. Pubes leguminis rigida. East and West Indies. The down which covers the outer surface of the pods of this plant, consists of very sharp spiculas, and is the part used as an anthelmintic. It is made into an electua- ry, with syrup or molasses, of which two tea-spoonfuls are given to an adult, and repeated two or three times, a strong cathartic being afterwards exhibited. Its action is entirely mechanical. In the West India Islands it is the common anthelmintic, and is described as being fre- quently successful. In this country it is more rarely used. Ferrum. Iron. Th e filings of this metal have been given as an an- thelmintic, in a dose of one or two drachms; and the sub-carbonate, or rust of iron, was highly recommended by Rush as a remedy against the tape worm, when taken to the extent of three or four drachms. ANTHELMINTICS. 375 Stannum. Tin. Tin is reduced to a powder, consisting of small rounded particles, by heating it nearly to its melting point, and agitating it briskly. Either this powder, or what has been recommended in preference, the metal, in filings, is used as an anthelmintic, in a dose of one or two drachms, or even in a much larger quantity. It is taken repeated- ly in the morning, and a cathartic is afterwards exhibit- ed. Its effect, so far as it operates, has been supposed to be mechanical, dislodging the worm from the mucus of the intestines by the grittiness of its particles. It is not improbable, too, that it may act by generating hydrogen gas in the intestinal canal, which proves noxious to the animal; and its efficacy has been said to be increased by • combination with sulphur, by which sulphuretted hydro- gen gas will be evolved. Olea Europjea. Olive Oil. Oleum Olivarum. Diand. Monogyn. Sepiarie. Oleum expressum. South of Europe. Olive Oil, or any other expressed oil, taken in the morning to the extent of half a pound, or as much as the stomach can bear, has been said to prove anthelmintic, but in the state of diffusion and mixture in which it must act on worms in the intestines, it can scarcely be expect- ed to have any certain power. Artemisia santonica. Wormseed. Syngen. Polygam. superfl. Composite. Semen. Persia. The seeds of this plant have a faint disagreeable smell, and a very bitter taste. They are in common use as an anthelmintic, and probably operate merely as a bit- ter; the dose is half a drachm, or a drachm of the pow- der to an adult. This, after being continued for some time, is followed by a dose of a strong cathartic. 376 ANTHELMINTICS. Spigelia marilandica. Indian Pink. Pentand. Monogyn. Stet- late. Radix. North America. The root and stalks of this plant are used in medi- cine, on the supposition of their anthelmintic power; they have a bitter taste; in a large dose prove purgative, and also sometimes narcotic. They are usually adminis- tered in the form of the watery infusion; in the quantity of half a drachm, or even to the extent of two or three drachms to an adult. Its operation as a narcotic has been said sometimes to be produced; and to prevent this, it has been recommended to be given rather in large than in small doses, as its cathartic operation, by which its narcotic power is obviated, is thus obtained. In its dried state, however, in which it is employed in this country, no unpleasant symptom follows from its administration. Polypodium filix mas. Male Fern. Cryptogamia. Filices. Radix. Indigenous. Th e root of this plant was once highly celebrated as a remedy against the tape worm; two or three drachms of the powder of it being taken in the morning, and a strong cathartic of jalap or gamboge given soon after it. The efficacy of the prescription probably depended entirely on the cathartic. Tanacetum vulgare. Tansy. Syngen. Polyg. superf. Compo- site. Folia et flores. Indigenous. The leaves and flowers of this plant have a strong bit- ter taste, with some aromatic quality, which resides in an essential oil. They have been recommended as anthel- mintic, and especially as capable of expelling the lum- brici, and are sometimes used as a popular remedy. The dose, in powder, is from one scruple to one drachm. Geoffr^ea inermis. Cabbage-Bark tree. Diadelph. Decand. Pa- pilionac. Cortex. Jamaica. Th e bark of this tree has an unpleasant smell, with a sweetish taste. It is used as an anthelmintic, and has been considered as one of considerable power, especially in ANTHELMINTICS. 377 expelling the lumbrici. It is usually given under the form of decoction, an ounce being boiled in two pounds of water, to one pound, and from one to two ounces of this being given as a dose to an adult. It usually operates as a cathartic, and in an over-dose is liable to occasion sickness and vomiting. The same symptoms are said to be induced by the incautious drinking of cold water du- ring its operation. When they occur from either cause. they are relieved by a dose of castor oil. Offic. Prep.—Decoct. Geoffr. Inerm. Ed. Cambogia. Gamboge. (Page 276.) Gamboge has been celebrated as a remedy against the tape-worm, and by its powerful cathartic operation is sometimes successful in expelling it. It is given in a dose from 5 to 20 grains by itself, or combined with two parts of acidulous tartrate of potash. It is frequently also given as a cathartic after other anthelmintics. Murias hydrargyri mitis. Mild Muriate of Mercury. Calomel. Several of the preparations of mercury have been employed as anthelmintics. Calomel is entitled to the preference, not only from its direct action as a mercurial, but also on account of its action on the intestinal canal. It is given by itself, in a dose of 10 or 12 grains to an adult, or in a smaller quantity, combined with jalap or rhubarb. It is also generally the basis of the cathartic usually administered after other anthelmintics have been continued for some time. Voe. I. 3 B 578 CHAPTER XXI. OF DEMULCENTS. Demulcents are defined, " Medicines suited to ob- viate and prevent the action of acrid and stimulant mat- ters; and that, not by correcting or changing their acri- mony, but by involving it in a mild and viscid matter, which prevents it from acting upon the sensible parts of the body," or by covering the surface to which they may be applied. Their action has been supposed to be exemplified in catarrh, where the irritation at the fop of the trachea, occasioning coughing, is removed by mu- cilaginous substances; or in gonorrhoea, where the sense of heat and pain from the application of the stimulus of urine to the inflamed surface of the urethra is prevented by similar means. Where these substances are directly applied to the part, it may be understood how this operation is obtained from them. But where they are received by the medium of the stomach into the circulating system, it has been supposed that they can have no such effect. They must be changed by the process of digestion, and lose that viscidity by which only they operate, so that they cannot afterwards be separated by any secretion in their original form. Hence their utility in gonorrhoea and similar affec- tions has been altogether denied. It is not clear, however, that such a conclusion is just. It is sufficiently certain, that many substances, which undergo the process of digestion, are afterwards separated in their entire state from the blood, by parti- cular secreting organs. There is no gland which has this power more particularly than the kidneys; substan- ces received into the stomach and digested, afterwards passing off in the urine with all their peculiar properties. Saccharine matter for example, there is reason to believe, can be separated in this manner; and it is equally proba- ble, that mucilaginous or oily substances, which form DEMULCENTS. 379 the principal demulcents, are capable of such a separa- tion. There can be no doubt, however, but that a great share of the relief demulcents afford in irritation, or in- flammation of the urinary passages, is owing to the large quantity of water in which they are diffused, by which the urine is diluted, and rendered less stimulating. Per- haps the relief is to be ascribed solely to this dilution: since no alteration is perceived in the quality of the urine, from the use of these substances. And, in general, we may consider demulcents as being merely substances less stimulating than the fluids usually applied to the parts. The diseases in which demulcents are used, are prin- cipally catarrh, diarrhoea, dysentery, calculus and gonor- rhoea. They art evidently not medicines of any great power; they are only calculated to alleviate symptoms, and may be freely used in as large quantities as the sto- mach will receive them. Demulcents may be arranged under the two divisions of Mucilages, and Expressed Oils. DEMULCENTS. Mimosa Nilotic a. Astragalus tragacantha. Linum usitatissimum. Alth^a officinalis. Malva sylvestris. Glycyrrhiza glabra. Smilax sarsaparilla. Cycas circinalis Orchis mascula. Maranta arundinacea. Triticum hybernum. Lichen icelandicus. Cornu cervi. Ichthyocolla. Amygdalus communis. Olea europ#a. Sevum ceti. Cera. 380 DEMULCENTS. Arabicum Gummi. Gum Arabic. Mimosa Nilotica. Polygam. Mo- noec. Lomentacee. Africa. Gum is a proximate vegetable principle, which is ob- tained by exudation, more or less pure, from a number of plants. The gum Arabic of commerce is not exclusive- ly the produce of one vegetable: that which is most pure, and used to be imported from Egypt, is from a species of mimosa. The London College admit, on the authority of Wildenow, a different genus, Acacia, as sub- stituted for that of Mimosa; they refer to the species pro- ducing this gum by the name Acacia Vera, and name the gum itself Gummi Acacias, while the Edinburgh College name it Gummi Mimosas Niloticae. The purest gum of the shops is in small irregular pieces, white or yellowish, semi-pellucid, without taste or smell: there are other varieties coarser, of a yellow or red colour. All of them have the properties of gum; are insoluble in al- kohol or oils, and soluble in water, forming a viscid solu- tion named Mucilage. Gum Arabic is in common use as a demulcent. In catarrh it is allowed to dissolve slowly in the mouth, and its mucilage is the basis of the mixtures usually employed to allay coughing. Sometimes, too, it is employed in te- nesmus, strangury, and ardor urince. In Pharmacy, muci- lage of gum Arabic is employed for a variety of pur- poses. It serves to suspend heavy powders in waters; to diffuse oils, balsams and resins in water, and give te- nacity to substances made into pills. Offic. Prep.—Emuls. Gummi Mimosae Nil. Ph. Ed. Dub—Muc. Gum. Mim. Nil. Ed. Lond. Dub.— Troch. Gum. Ed. Astragalus tragacantha. Tragacanth. Diadelph. Decand» Papilionacee. Gummi. South of Europe, Asia. Tragacanth is obtained by exudation: the plant producing it, a native of Persia, is said to differ from the Astragalus Tragacantha of Linnasus; it is described by Olivier as a distinct species, under the name of Astra- DEMULCENTS. 381 galus Verus; and this is admitted by the London Col- lege. Tragacanth is iii small wrinkled pieces, semi-trans- parent and brittle, and has neither taste nor smell. It is regarded as a gum, yet it differs from the other pure gums in not being perfectly soluble in cold water: it is softened and diffused, but remains flocculent and turbid. When heat is applied, it communicates to the water a great degree of viscidity, but still the solution remains turbid. It is greatly superior to all the gums, in giving viscidity to water; its power in this respect being to that of gum Arabic as 1 to 24. Tragacanth has virtues similar to gum Arabic. It is less employed, except in some pharmaceutical processes, in which, from its greater viscidity, it is preferred, as in making of troches. Offic. Prep.—Mucil. Astrag. Trag. Pharm. Ed. Dub. —Pulv. Trag. C. Lond. Linum usitatissimum. Flax. Pentand. Pentagyn. Gruinales. Semen. Indigenous. The seeds of this plant afford a strong mucilage by infusion or decoction in water, which has no unpleasant taste or smell. These preparations of it are, therefore, frequently used as demulcents in catarrh and gonorrhoea, in a dilute state, being rendered more grateful by the ad- dition of a little sugar and lemon juice. Offic. Prep.—Infus. Lini, Ph. Lond. Alth-ka officinalis. Althaea. Marsh-mallow. Monadelph. Poly- and. Columnifere. Radix. Indigenous. All the parts of this plant yield a mucilage by infu- tion or decoction in water: the root does so most abun- dantly, and freed from its outer bark, is kept in the shops. Its mucilage is similar to that from lintseed, and is used for the same purposes. It is even preferable, as being more pure. Offic. Prep.—Decoct. Alth. Off. Ph. Ed.—^r. Alth. Off. Ed. Lond. 382 DEMULCENTS. Malva sylvestris. Common MallovV. Monadelph. Polyand. Columnifere. Folia. Indig. The leaves of this plant afford a mucilage by infusion in water, weaker, however, than that from lintseed or althaea. The plant is therefore little used, and might be discarded. Offic. Prep.—Decoct. Malv. Comp. Ph. Lond. Glycyrrhiza glabra. Liquorice. Diadelph. Decand. Papilionac. Radix. South of Europe. The root of this plant has a sweet agreeable taste, with no flavour. This sweetness is extracted by water by infusion or decoction; and by evaporation a dark coloured extract of the same sweet taste is obtained, consisting principally of saccharine and mucilaginous matter. Alkohol likewise extracts the sweetness of liquorice, with less of the mucilage. Liquorice-root is employed as a demulcent, and on ac- count of its sweet taste is frequently added to infusions of lintseed, or althaea. Its watery extract is also in common use as a demulcent in catarrh, being allowed to dissolve slowly in the mouth. Offic. Prep.—Extr. Glycyrrh. Gl. Ph. Ed. Dub.— Troch. Glycyrrh. Troch. Glycyrrh. cum Opio, Ed. Smilax sarsaparilla. Sarsaparilla. Dicecia Hcxand. Sarmenlacee.. Radix. South America. This root is in long slender twigs, internally white, and covered with a brownish bark: it has scarcely any smell; its taste is mucilaginous, and slightly bitter. Water extracts its bitterness; by beating it with water, a portion of fecula is separated, white and insipid, in which the virtues of the root appear to reside. For pharmaceutic preparation it is split and cut into small pieces. Sarsaparilla produces no sensible effect on the system, and it can scarcely be regarded except as a demulcent, when given under its usual form of decoction. It has DEMULCENTS. 383 however, been considered as a specific in the treatment of some venereal affections, paiticularly those of the bones or periosteum, and as a restorative in that state of debility which is the consequence of the disease protracted, or of the mercurial irritation. It has also been recommended in extensive ulceration, in cutaneous affections, and in chronic rheumatism. It is given in the form of decoc- tion, and is very frequently joined with guaiac and meze- reon, the pungency of which at least it covers. Offic. Prep.—Dec. Smil. Sarsap. Ph. Ed. Lond. Dub. —Dec. Sarsap. Comp. Lond. Dub.—Extr. Sarsaparill. Lond. Cycas circinalis. Sago. Cryptogamia. Filices. East Indies. Sago is a fecula obtained from the pith or medullary part of the branches of the plant, by maceration in water. It is in small grains of a brownish colour, without taste or smell. Boiled in milk or water, it dissolves entirely; and this with sugar, and the addition frequently of a litde wine, forms a nutritious jelly, prescribed in diarrhoea as a demulcent, and in convalescence as a nutritious article of diet, easy of digestion. Orchis mascula. Salop. Gynand. Diand. Orchidee. Indigenous. The root of this plant, by maceration in water and beating, affords the fecula known by the name of Salop. Its qualities and virtues are similar to those of Sago. Maranta arundinacea. Monand. Monogyn. Scitaminea. South America. The fecula which has been lately introduced under the name of Arrow-Root Powder, has been said to be the produce of this plant, though there is now generally substituted for it the fecula of some indigenous plants. It is used as a demulcent in diarrhoea and dysentery, and as a nutritious article of diet for convalescents. It forms a jelly by boiling with water or milk, and it is under this form that it is taken. 384 DEMULCENTS. Triticum hybernum. Wheat. Triand. Digyn. Gramina. Fecula seminum. Amylum. Starch, the fecula of wheat, obtained by beating the grains previously soaked in water, forms a gelatinous so- lution when boiled with water, which is used is a demul- cent. It is sometimes given as an enema in tenesmus, and is the common vehicle for giving opium under that form. Offic. Prep.—Mucilag. Amyli, Ph. Ed. Lond. Dub. Lichen islandicus. Iceland LAverxirort.Cryfitogamia Alge. Iceland. The different lichens contain a kind of mucilaginous matter or fecula, which is extracted by boiling in water. The lichen islandicus consists principally of this kind of matter, with a portion of extractive principle having a degree of bitterness. This bitterness is removed by ma- ceration in cold water, and then by decoction with wa- ter a gelatinous solution is obtained. This is used as an article of diet in the countries of which this lichen is a native; and it has been introduced into medical practice as a demulcent, and a nutritious substance easy of diges. tion. The decoction has received a place in the London Pharmacopoeia. Offic. Prep.—Decoct. Lichenis, Ph. Lond. Dub. Cornu cervi rasura. Hartshorn Shavings. Cervus Elaphus, Cornu. Mammalia. Pecora. Bone, and horn which is of similar composition, con- tain a considerable quantity of gelatin, along with phos- phate of lime. The horns of the deer have been suppos- ed to afford this in the purest state, and they have there- fore been received into the Materia Medica. They are freed from their outer rough covering, and the internal white part is rasped down for use. The shavings afford, by decoction in water, a jelly, which, rendered grateful by sugar, and a little wine, is used in diarrhoea and dysen- tery as a demulcent, and in convalescence as a light nu» tritipus article of diet. DEMULCENTS. 385, Ichtkyocolla. Isinglass. Acipenser Sturio. Pisces. Chondrop- terygii. Isinglass is obtained from the skin and other parts of the sturgeon, as well as several other kinds of fish caught in the northern seas. The internal skin is boil- ed in water; the strained decoction is inspissated; and the solid mass formed into convoluted pieces is the isinglass of the shops. It is nearly pure gelatin, is almost entirely soluble in water by boiling, forming a gelatinous solu- tion, which has sometimes been employed as a demul- cent. Amygdalus communis. Icosandria. Monog. Pomacee. Fructus; Nucleus; Ol. Express. South of Eur op'. The kernel of the fruit of the almond is farinaceous with a portion of expressed oil. This oil is obtained by expression from the seeds, or by decoction of them in water. It is very similar to the olive oil, but purer, and more free from any rancidity. In common with express- ed oils, it has the properties of a demulcent; and diffused in water by the medium of mucilage, or a few drops of an alkaline solution, it is given in catarrh. There is another mode in which this oil is given as a demulcent, more grateful, that of emulsion. The almonds are triturated with water; the oil is diffused in the water by the medium of the mucilage and fecula of the almond, and a milky-like liquor is formed, which is used as a pleasant demulcent and diluent, particularly to obviate strangury from the application of a blister. Offic. Prep.—Emuls. Amygd. Ph. Ed. Lond. Dub. —Confect. Amygd. Ph. Lond. Olea europjea. Olive Oil. (Page 375.) The oil obtained from the fruit of the olive by expres- sion, is of a light yellowish or greenish colour, without either taste or smell. It is the expressed oil which is most commonly used in medicine. It is employed as a demul- cent in catarrh, and some other affections, diffused in Vol. I. 3 C 386 BEMULCENTS. water by the medium of mucilage, or by a very small quantity of one of the alkalis, and is thus taken in as large quantities as the stomach can bear; it may be doubted, however, whether with any advantage. Its application as an anthelmintic has been already noticed. Externally it is used as an emollient. Sevum ceti. Spermaceti. Physeter Macrocephalus. Mammali*. Cetacea. This fatty matter is obtained from the head of the par- ticular species of whale above stated. The cavity of the head contains a large quantity of an oily fluid, from which, on standing, a concrete substance separates. This, freed from the oil by expression, and purified by melting and boiling with a weak alkaline solution, is the common spermaceti. It is in white flakes, unctuous and friable, and has neither taste nor smell. Its chemical properties are the same as those of the expressed oils and fats, except that it does not easily unite with the alkalis, and that it is soluble to a certain extent in alkohol and ether. Its medicinal virtues are those of a mild demulcent, and as such it is given in catarrh and gonorrhoea, mixed with sugar, or sometimes diffused in water by the medium of the yolk of an egg. It enters as an unctuous substance into the composition of ointments. Offic. Prep.—Cerat. Cetacei, Unguent. Cetaceae, Ph. Lond. Cera. Wax.—This is a concrete substance of a particular nature, supposed to be collected from the an- therae of vegetables by the bee. The experiments of Hu- ber appear to have proved, that it can be formed by this insect from changes produced on it by its saccharine food. Still it is to be regarded as a vegetable product. It exists in the fruit and flowers of many plants, and some, as the Myrica Cerifera, afford a substance perfectly ana- logous in large quantity. Wax, in its chemical proper- ties, resembles most nearly the expressed oils, differing from them principally in solidity, and in combining less DILUENTS. 387 readily with the alkalis. It is of a yellow colour, but by bleaching can be rendered white. Wax has been used as a demulcent in dysentery, be- ing diffused in water by means of mucilage of gum Ara- bic, but it has no particular quality to recommend it. It is used in the composition of ointments and plasters, communicating to them consistence and tenacity. Offic. Prep.—Emp. Cerae, Ph. Ed. Lond. CHAPTER XXII. OF DILUENTS. Diluents have been defined, Substances which in- crease the fluidity of the blood, by augmenting the pro- portion of fluid in it. Watery liquors, it is obvious, will have this operation to a certain extent, and, strictly speak- ing, water can be regarded as the only proper diluent. But different mild substances are added to it to render it pleasant, and frequently to communicate to it a demulcent quality, diluents and demulcents being generally em- ployed to answer the same indications. Diluents are prescribed principally in acute inflamma- tory diseases, with the views of quenching thirst, and diminishing the stimulating quality of the blood. They are employed too to favour the operation of sweating, being given tepid; and sometimes to promote the action of diuretics, especially of those which are saline. And there are some chronic diseases in which diluents appear ad- vantageous. Some mineral waters, celebrated for their efficacy, are found to be nothing but water uncommonly pure, such as the Malvern Water; and the advantage de- rived from these in scrofulous affections is probably to be attributed to mere dilution. 388 CHAPTER XXIII. OF EMOLLIENTS. The class of Emollients, according to^ the definition given by Cullen, includes those medicines which dimi- nish the force of cohesion in the particles of the solid matter of the human body, and thereby render them more lax and flexible. Their operation is evidently mechanical; they are insinuated into the matter of the solid fibre, and either diminish its density, or lessen the friction between its particles. Hence they are useful where the fibres are rigid, or where they are preternaturally extended, and therefore afford relief when topically applied to inflamed parts, to tumours distending the skin, or where the skin is dry and rigid. There may be included under the same class, those substances which, applied to the surface, by their smoothness and bland quality afford relief from any irritation. Heat, conjoined with moisture, is the principal emol- lient. Warm water is of itself useful; but when applied, by the medium of some vegetable substances, as in the different fomentations and cataplasms, it is more advan- tageous as the heat is longer retained, and as it can be more conveniently applied. The emollient power is little increased by such additions, though some have supposed that the mucilaginous vegetables have some efficacy of this kind. The other emollients are the oils or unctuous sub- stances: they are merely introduced by friction; and in distention of the animal fibre, as, for example, in dropsical swelling, they afford some relief. Any of the expressed oils or lard may be used for this purpose. Axungia Por- cina, Hogs' Lard, is the only substance of this kind not hitherto noticed. It is the fat of the hog, freed from the membranous threads or cellular fibre with which it is intermingled. This is done by melting it with the addi- EMOLLIENTS. 389 tion of a little water to prevent the heat from rising too high: it collects on the surface of the water, and when cold, becomes concrete. It forms the common basis of ointments, which are applied as a dressing to inflamed par * Such compositions too are formed from any of the expressed oils, melted with a due proportion of sperma- ceti or wax: they prove useful in a great measure by ex- cluding the air, v\ hile, from their smoothness and soft- ness, they excite no irritation. The thick and bland liquid formed by the combination of lime water with expressed oils, (Linimentum Aquae Calcis), is another emollient composition, usually employed as a soothing application to burns, and proving useful by a similar operation. APPENDIX TO VOLUME FIRST. IN concluding the history of the articles of the Materia Medica, I have thought it proper to present a view of that arrangement in which they are associated, according to their natural characters. In classing these substances on this principle, they have usually been comprised under the three leading divisions, of Mineral, Vegetable, and Animal substances. The first of these divisions, however, is either not sufficiendy comprehensive, or too great an extension must be given to the signification of the term applied to the class, so as to bring under it substances which cannot be referred to either of the others, and which, at the same time, cannot be regarded as belonging to what is strictly denominated the Mineral Kingdom. A more correct division, therefore, is, into the two great Classes of Unorganized Substances, and of Substances which are the products of Organization, the latter com- prising the vegetable and animal products, while the for- mer may include all the other articles of the Materia Medica. The substances belonging to the first, may be subdivided according to their chemical relations; those belonging to the second, according to their natural affi- nities. Thus, under the one will be placed the orders of Salts, Earths, Inflammables, Metals, Waters, and Airs. Under the other, both Vegetable and Animal Substances may be arranged according to the usual classes of the Linnzean System. With regard to vegetables, some have 392 APPENDIX. indeed preferred associating them as they belong to the natural families or orders of plants; for as in these the arrangement is founded not on arbitrary characters, but on similarity of structure and organization, those sub- stances, it has been imagined, will be brought together, which are possessed of similar powers. But this system of natural classification is still so defective, that This has been hitherto very imperfectly attained, and, under the same order, plants of the most discordant qualities are placed. There is therefore no advantage in departing from the more usual arrangement. There are some substances, such as the vegetable acids, which may be placed under either general division. They are strictly products of operations depending on organization: they can also, however, be formed by arti- ficial processes; and from their chemical constitution, I have not hesitated to associate them with the substances to which they appear to have the most strict relation. TABULA MATERIA MEDICO I. INORGANICA. CLASSIS I—SALES. ORDO--ACIDA. Acidum sulphuricum. nitrosum. nitricum. muriaticum. oxy-muriaticum. phosphoricum. carbonicum. aceticum. tartaricum. citricum. benzoicum. OIID.—ALKALIA. Potassa. Soda. Ammonia. ORD.—SALES NEUTRI. Sulphas potassae. Sulphas sodae. Nitras potassae. Murias sodae. Murias ammoniae. Oxy-murias potassx. Phosphas sodae. Carbonas potassae. Vol. I. Sub-carbonas potassae. Super-carbonas potassae. Carbonas sodae. Sub-carbonas sodae. Super-carbonas sodae. Carbonas ammoniae. Sub-carbonas ammoniae. Sub-boras sodae. Acetas potassae. Acetas ammoniae. Super-tartras potassae. Tartras potassae. Tartras potassae et sodae. Citras potassae. Citras ammoniae. Ci. 11.—TERRJF-. Calx. Carbonas calcis, Murias calcis. Phosphas calcis. Baryta. Murias barytae. Magnesia. Carbonas magnesiae. Sulphas magnesiae. 3D 394 TABULA Murias magnesiae. Argilla. Super-sulphas argillae et potas- sae. Ci.. III.—1NFLA.MMABILIA. Sulphur. Sulphuretum potassae. Hydro sulphuretum ammoniae. Phosphorus. Carbo. Petroleum. Alkohol. Ether sulphuricus. Ether nitricus. Cl. IV.—METALLA. Argentum. Nitras Argenti. Hydrargyrum. Oxidum hydrargyri per tritura- tionem. Oxidum hydrargyri cinereum. Oxidum hydrargyri rubrum. Sub-sulphas hydrargyri flavus. Nitras hydrargyri. Sub-nitras hydrargyri ruber. Murias hydrargyri corrosivus. Murias hydrargyri mitis. Murias hydrargyri et ammoniae. Acetas hydrargyri. Phosphas hydrargyri. Sulphuretum hydrargyri ni- grum. Sulphuretum hydrargyri ru- brum. Ferrum. Oxidum ferri nigrum. Oxidum ferri rubrum. Sulphas ferri. Murias ferri. Murias ferri et ammoniae. Carbonas ferri. Acetas ferri. Tartras ferri et potassae. Carbonas ferri et potassae. Cuprum. Sulphas cupri. Sub-acetas cupri. Ammoniuretum cupri. Plumbum. Oxidum plumbi semi-vitreum. Sub-acetas plumbi. Acetas plumbi. Super-acetas plumbi. Stannum. Zincum. Oxidum zinci. Carbonas zinci. Sulphas zinci. Acetas zinci. Bismuthum. Antimonium. Sulphuretum antimonii. Oxidum antimonii sulphuretum. Oxidum antimonii hydro-sul- phuretum. Oxidum antimonii vitrificatum. Oxidum antimonii album. Oxidum antimonii cum phos- phate calcis. Murias antimonii. Tartras antimonii et potassae. Arsenicum. Oxidum arsenici album. Arsenias potassae. Cl. V.—AQUJE Aqua pura. Aqux minerales. Aquae minerales carbonatae. salinae. sulphureas. ferrugineae. Aqua marina. MATERIA MEDICO. Gas oxidum nitrosum. 395 GL.VL—GASEA. ORD.--GASEA EXCITANTIA. Gas oxygenium. ORD.--GASEA SEDANTIA. Gas nitrogenium. Gas hydrogenium. Gas acidum carbonicum. Gas hydrogenium carburetum. ELECTR1CITAS. GALVAN1SMUS. II. ORGANICA. VEGETABILIA.* CLASS1S—MONANDRIA. Cl.—TRIANDRIA ORD.--MONOGYNIA. Amomum repens.f Amomum zingiber.\ Amomum zedoaria. Cl.—DI\NDRIA. ORD.—MONOGYNIA. Olea Europaea. Rosmarinus officinalis. Salvia officinalis. Gratiola officinalis. ORD.--MONOGYNIA Valeriana officinalis. Crocus sativus. Iris florentina. ORD.—DIGYNIA. Saccharum officinarum. Triticum hybernum. Cl.—TETRANDRIA. ORD.—TRIGYNIA. Piper nigrum. longum. caudatum. ORD.--MONOGYNIA. Rubia tinctorum. Santalum album. Dorstenia contrayerva. * From the progress of botanical knowledge, changes are necessarily made with regard to the specific or generic distinctions of the plants em- ployed in medicine. Wherever these appear to be fully established, I have admitted them in the following tables: but where they have been only lately introduced, and remain somewhat doubtful, I hare thought it preferable to retain the old name and arrangement, indicating only in a note the change that has been proposed, and the Pharmacopoeia in which it has been adopted. Under the history of the substance referred to in the body of the work, will be found the authority on which the proposed alteration rests. f Elettaria Cardamomum, Ph. Lond. * Zingiber Officinale, Ph. Lond. 39b TABULA Cl—PEN1ANDRIA. ORD.--MONOGYNIA. Hyoscyamus niger. Atropa belladona. Nicotiana tabacum. Datura stramonium. Solanum dulcamara. Strychnos nux vomica. Capsicum annuum. Cinchona officinalis.* Anchusa tinctoria. Spigelia marylandica. Callicocca ipecacuanha. Convolvulus jalapa. Convolvulus scammonium. Rhamnus catharticus. ORD--DIGYNIA. Gentiana lutea. Conium maculatum. Ferula assafoetida. Bubon galbanum. Carum carui. Coriandrum sativum. Pimpinella anisum. Anethum foeniculum. Angelica archangelica. ORD.--TRIGYNIA. Rhus toxicodendron. ORD.--PENTAGYNIA. Linum usitalissimum. Cl.—HKXANDRIA. ORD.--MONOGYNIA. Calamus acorus. Allium sativum. Scilla maritima. Aloe spicata. Cl.—HEPTANDRIA. ORD.--MONOGYNIA. jEsculus hippocastanum. Cl.—OCTANDRIA. ORD.—MONOGYNIA. Amyris opobalsamum. Daphne mezereum. ORD--TRIGYNIA. Polygonum bistorta. Cl.—ENNE \ NDUI A. ORD--MONOGYNIA. Laurus cinnamomum. Laurus cassia. Laurus camphora. Laurus sassafras. ORD.— TRIGYNIA. Rheum palmatum. Cl.—DKCA.NDRIA. ORD.--MONOGYNIA. Cassia senna. Cassia fistula. Ruta graveolens. Guaiacum officinale. Toluifera balsamum. Myroxylon peruiferum. Styrax officinale. Styrax benzoinum. Copaifera officinalis. Haematoxylon Campechianum. Swietenia febrifuga. Swietenia mahagoni. Quassia amara. Quassia simarouba. Arbutus uva ursi. Rhododendron chrysanthum. Cl.—DODKCANDR1A. ORD.--MONOGYNIA. Asarum Europaeum. Canella alba. ORD --TRIGYNIA. Euphorbia officinalis. * Cinchona cordifolia, lancifolia, et oblongifolia, Ph. Lond. MATERLE MEDICJE. 397 Cl.—ICOSANDRIA. Cl.—MONADELPHIA. ORD---MONOGYNIA. Myrtus pimenta. Prunus lauro-cerasus. Amygdalus communis. Eugenia caryophyllata. OHD---POLYGYNIA. Rosa centifolia. Rosa rubra. Tormentilla erecta.* Cl.—POl A ANDRIA. ORD.--MONOGYNIA. Papaver somniferum. ORD--TRIGYNIA. Aconitum napellus. ORD.--POLYGYNIA. Helleborus niger. Cl.—DIUYNAMIA. ORD.--GYMNOSPERMIA. Hyssopus officinalis. Mentha piperita. Mentha viridis. Mentha pulegium. Lavandula spica. ORD.—ANGIOSPERMIA. Digitalis purpurea. Cl.—TETRAUYNAMIA. ORD.--SILICULOS.E. Cochlearia armoracia. ORD.—SILIQUOS.E. Sinapis alba. ORD---TRI ANDRIA. Tamarindus Indica. ORD.--POLYANPRIA Althaea officinalis. Malva sylvestris. Cl.—D1AI1KLPHIA. ORD.--OCTANDRIA. Polygala senega. ORD.--DKCANDRIA. Pterocarpus santolinus. draco. Dolichos pruriens. Geoffroya inermis. Glycyrrhiza glabra. Astragalus tragacantha.} Cl—POLYADELPHIA. ORD.--ICOSANDRIA. Citrus aurantium. Citrus medica. ORD.--POLY ANDRIA. Melaleuca leucadendron.f Cl.—SYNGENESIA. ORD.--POLYGAMIA iEQUALIS. Lactuca virosa. ORD.—POLYGAMIA SUPERFLUA. Artemisia santonica. Artemisia absinthium. Anthemis nobilis. Anthemis pyrethrum. Arnica montana. » Tormentilla officinalis. f Astragalus verus, Ph. Lond. 4 Melaleuca cajuputi, Ph. Lond. 398 TABULA Cl—GYNANDRIA. ORD.--DI ANDRIA. Orchis mascula. Humulus lupulus. ORD.<—HEX ANDRIA. Smilax sarsaparilla. ORD.-—HEX ANDRIA. Aristolochia serpentaria. ORD.--POLY ANDRIA. Arum maculatum. i Cl—MONOZCIA. ORD.--POLY ANDRIA. Quercus pedunculata. Quercus cerris. ORD—MONADELPHIA. Pinus balsamea. Pinus larix. Pinus sylvestris. Pinus abies. Pinus picea. Croton eleutheria. Ricinus communis. ORD--SYNGENESIA. Momordica elaterium. Cucumis colocynthis. Bryonia alba. Cl.—D1CECIA. ORD.--MONADELPHIA. Juniperus communis. Juniperus sabina. Myristica moschata. Cl.—POLYGAMIA ORD.--MONOECIA. Veratrum album. Stalagmitis cambogioides. Mimosa nilotica.* Mimosa catechu.f ORD.--DIOECIA. Fraxinus ornus. ORD--PENTANDRI A. Pistacia lentiscus. Cl— CRYPTOGAMIA ORD.—PILICES. Polypodium filix mas.$ Cycas circinalis. Ammoniacum.§ Sagapenum. Myrrha. Kino.H Angustura.T Colombo. * Acacia vera, Ph. Lond. t Acacia catechu, Ph. Lond. * Aspidium filix mas, Ph. Lond. §Heracleum gummiferum, Ph. Lon. || Eucalyptus resinifera, Ph. Ed. Bute a frondosa, Ph. Dub. H CuspariaTebrifuga, Ph. Lond. MATERIA MEDICJE. 399 ANIMALIA. CLASSIS.—MAMMAUA. Moschus. Castoreum. Cornu cervi. Sevum ceti. Axungia porcina. Sevum ovillum. Cl.—PISCES. Ichthyocolla. CL.—INSECTA. Meloe vesicatorius.** Cera. Coccinella. Lapilli et chelae cancrorum. Cl—VERMES. Os saepiaco Corallium. Spongia. Lytta vesicatoria END OF VOLUME FIRST Med.. Hist Z.10 Ills' y. I s