A PRACTICAL LABORATORY COURSE IN Medical Chemistry BY JOHN 0. DRAPER, M.D., LL.D. PROFESSOR OF CHEMISTRY IN THE MEDICAL DEPARTMENT UNIVERSITY OF NEW YORK, AND OF PHYSIOLOGY AND NATURAL HISTORY IN THE COLLEGE OF THE CITY OF NEW YORK NEWYORK WILLIAM WOOD & COMPANY 56 & 58 Lafayette Place 1882 COPYRIGHT BY WILLIAM WOOD & COMPAHY 1882 Trow’s Printing and Bookbinding Company 201-213 East 12th Street NEW YORK CONTENTS. INTRODUCTION. [The figuyes in heavy type denote the number of the Article.] Object of the Course, 1. General Manipulation, 2. Solution, 3 ; simple solution, 4; decantation and filtration, 5 ; evapora- tion and desiccation, 6; distillation, 7 ; incineration, 8. Chemical Divisions of Substances, 9. Definitions, 10 ; inorganic and organic substances, 11 ; experimental demonstrations, 12; Base acid salt, 13 ; reaction, 14. Divisions of the Course, 15. SECTION 1. POISONS. General Characters, 16. Physiological divisions, 17 ; chemical divisions, 18 ; purifications, 19. INORGANIC POISONS. Arsenic : Preparations, 20 ; heat test, 21 ; HCI and EPS test, 22 ; NH4HS test, 23 ; ammonio-sulphate copper test, 24 ; ammonio-nitrate silver test, 25 ; Eeinsch, 26 ; Marsh, 27 ; toxicology, 28 ; antidotes, 29. Antimony : Preparations, 30 ; heat test, 31 ; HCI and EPS test, 32 ; ammonio-copper and silver tests, 33 ; Eeinsch, 34 ; Marsh, 35 ; toxicology, 36 ; an- tidotes, 37. CONTENTS. IV Mercury ; Preparations, 38 ; heat test, 39 ; HCI and H2S test, 40 ; differentiating tests, 41 ; additional ic tests, 42 ; Reinsch test, 43; galvanic test, 44; toxicology, 45 ; antidotes, 46. Lead : Preparations, 47; heat test, 48 ; HCI and H2S test, 49 ; special tests, 50; toxicology, 51 ; antidotes, 52. Copper: Preparations, 53 ; heat test, 54 ; HCI and H2S test, 55 ; NH4HO test, 56; KHO test, 57; deoxidation test, 58; Fehling’s solution, 59; Ferrocyanide and other tests, 60 ; toxicology, 61; antidotes, 62. Analytical Table for Metals, 63. Phosphorus : Preparations, 64; tests, 65 ; toxicology, 66 ; antidotes, 67. Acids, 68. Mineral Acids, 69. Tests, 70; toxicology, 71 ; antidotes, 72. Oxalic Acid, 73. Tests, 74; toxicology, 75 ; antidotes, 76. Hydrocyanic Acid, 77. Tests, 78 ; toxicology, 79 ; antidotes, 80. Alkalies, 81. Tests, 82; alkalimetry, volumetric analysis, 83; toxicology, 84; anti- dotes, 85. ORGANIC POISONS. ALKALOIDS, 86. Morphia, 87. Tests, 88 ; toxicology, 89 ; antidotes, 90. Strychnia, 91. Tests, 92 ; toxicology, 93 ; antidotes, 94. References to Authors, 95. SECTION 11. Foreign Substances in, 97. Sources of Supply, 98. Examination for Organic Impurities, 99. WATER, 96. CONTENTS. Inorganic Impurities, 100, Origin of inorganic impurities, 101 ; hard and soft waters, 102 ; inor- ganic residue, 103; potassium reaction, 104; sodium reaction, 105; calcium reaction, 106; examination, 107. Purification, 108. SECTION 111. ANIMAL FLUIDS. General Composition, 109. Specific Gravity, 110. Effect of temperature on, 111. Proteids, 112. Tests, 113; Millon’s reagent, 114; albumen, 115 ; tests for, 116; al- buminates, 117 ; casein, 118 ; fibrin, 119. Milk, 120. Condensed milk, 121 ; spontaneous changes in milk, 122 ; tests, 123 ; impure milk, 124. Blood, 125. Spontaneous changes in blood, 126 ; spectroscopic examination of, 127 ; tests, 128 ; blood stains, 129. Bile, 130. Pigment tests, 131; bile salts tests, 132; cholesterin, 133. Urine, Normal, 134. Physical characters, 135; chemical characters, 136; reaction, 137; composition, 138. Urine Abnormal, 139. Variation in Normal Ingredients, 140. Urea, 141. Increase of, 142 ; decrease of, 143 ; absolute quantity, 144. Uric Acid, 145. Increase, 146; heat test, 147; murexid test, 148. Chlorides, 149. Increase, 150; decrease, 151 ; tests, 152. Phosphates, 153. Increase, 154; decrease, 155; tests, 156; approximate quantity, 157. Sulphates, 158. Increase and decrease, 159; tests, 160. Abnormal Constituents : Albumen, 161. Heat tost, 162 ; nitric acid tost, 163 ; nitric acid and urates, 164 ; nitric acid and coloring matters, 165 ; nitric acid and carbonates, 166. CONTENTS. VI Blood, 167 ; tests, 168. Bile, 169; tests, 170. Sugar, 171 ; tests, 172. SECTION IV. SEDIMENTS AND CALCULI. General Characters, 173. Gouty Concretions, 174. Salivary Concretions and Tartar, 175. Biliary Calculi, 176. Urinary Sediments, 177. Acid fermentation of urine, 178; alkaline fermentation of urine, 179. Urinary Sediments, Classified, 180. Unorganized Sediments ; Urates, 181; phosphates, 182; oxalates, 183; uric acid, 184; mixed deposits, 185; separation of constituents, 186. Organized Sediments : Pus, 187; mucus, 188; blood, 189; cystine, 190; fat, 191; chyle, 192; epithelium and casts, 193; spermatozoa, 194; parasites, 195 ■ extraneous objects, 196. Urinary Calculi, 197. MEDICAL CHEMISTRY. INTRODUCTION. I. It is the object of the following course to give to medical students suf- ficient practice in chemical manipulation to enable them to perform in a sat- isfactory and reliable manner those tests which are required of the practising physician, and also to give them some experience in the use of chemical symbols, formulae, and equations. The time of the medical student is so occupied during a regular college session by the numerous branches he is required to study, that only a few hours are available for practical chemistry. These we have endeavored to utilize to the best advantage. The laboratory course is, therefore, confined to instruction in manipulation and to the study of tests which are useful in forming a correct diagnosis, or in solving hygienic problems. The more extended operations required to make a toxicological examination and the greater experience and knowledge necessary to defend the same in court should always lead the physician to transfer these examinations to a chemi- cal expert. Every other page is left blank in order that the student may record in its proper place the results of the experiments he makes and of additional facts obtained from oral instruction. The experiments to be performed by the student have been put in large type. Quantities are indicated by the signs employed in writing prescriptions, the object being to give students practice in their use. 2. The following methods of manipulation especially command our atten- tion : Ist, solution ; 2d, decantation and filtration ; 3d, evaporation or desic- cation ; 4th, distillation ; sth, incineration. GENERAL MANIPULATION. Solution. 3. A leading condition for the action of substances on each other is that one or both shall be in the liquid state. This may be accomplished in three ways: Ist, by solvents which impart the required state without changing the properties of the substance—this we may call simple solution ; 2d, by fusion or melting, which also leaves the properties unchanged, and Bd, by decomposition by acids, or in other ways ; the properties in this case under- go great changes. The first of these requires further explanation. INTRODUCTION. Simple Solution and Solvents. 4. The solvents generally employed are water, alcohol, ether, chloroform, and bisulphide of carbon. Unless otherwise stated, water is understood to he the menstruum. First.—The solution is prepared by the action of cold water upon the substance. In the case of organic bodies, as the different kinds of hark ; this is known as a cold infusion, e.g., wild cherry bark infusion. Second. —Boiling water is poured upon the substance ; this is technically known as a hot infusion, e.g., tea. Third.—The substance is boiled with water for some time; this is called a decoction, e.g., litmus water. Fourth.—When alcohol is used as the solvent, the preparation is com- monly called a tincture. Decantation and Filtration. 5. The action of the solvent having been promoted by agitation, the nndissolved portions are allowed to settle, when the clear solution is care- fully poured off ; this is called decantation. The operation of pouring without loss may be conducted by holding a solid glass rod vertically against the lip of the vessel from which the liquid is passing. It thus guides the fluid into the other vessel and prevents it from running down the side of that from which it is poured. For the complete separation of dissolved from undissolved mat- ter, filtration must be employed. An unsized paper, called filter paper, is prepared for this purpose. It should be cut into circles of various sizes; a very convenient size is three inches in diameter. Taking one of these circles, fold it exactly in two, then fold it again exactly at right angles to the first folding; it is now in four layers. Open it out, holding three of the layers together, and a conical cup is formed. Set this in a funnel of suitable size, mois- ten the paper with a little water, stand the funnel stem down in a test-tube, or flask, and the filter is ready. Pour into the paper cup the mixture to be operated upon ; the fluid passes through, and the insoluble matter remains in the cup. Wash the solid contents of the filter or cup with water or other menstruum employed until all soluble portions are removed. Evaporation or Desiccation 6, Is employed for the separation of a solid substance from the fluid in which it is dissolved. For this purpose shallow porcelain dishes, or watch- glasses, are used. The large extent of surface of these vessels promotes the escape of the vapor. Heat may be applied either directly to the vessel, or it may be placed on a water-bath, and the temperature thus kept below 212° F., or 100° C. The hot-air oven is a double vessel. The space between the two walls be- ing filled with water, the temperature is raised to any required degree be- low 212° F., as indicated by a thermometer placed therein. The substance to be dried is placed in the inner vessel through which air passes. INTRODUCTION. 3 Where the desiccation is to be accomplished at a very low temperature, it is conducted over strong sulphuric acid in an air-pump vacuum. Distillation 7. Is employed for the more or less complete separation of a volatile from a less volatile liquid, e.g., alcohol from water. The apparatus required is a retort, or other vessel in which evaporation may he conducted either directly, or by the water-bath ; and a flask, or other form of condenser, in which the vapor may be cooled and forced to reassume the liquid state. This process must be resorted to in the detection of the volatile poisons, like alcohol, hydrocyanic acid, etc. Incineration §. Is employed to separate non-volatile inorganic substances from those which are organic or volatile. It is generally conducted in a capsule or spoon made of platinum ; very few substances act upon this metal, and it can withstand a very high temperature. For the practical application of this process, see article 12. CHEMICAL DIVISIONS OF SUBSTANCES. 9. Three kinds of subdivision of bodies are used in chemistry; 1, ele- ment and compound ; 2, inorganic and organic ; 8, base, acid, and salt. For the proper study of the subject our ideas regarding these and certain other terms must be as exact as possible. Element and Compound with Definitions. 10. An element or radical is a body which has not yet been decomposed, e.g., oxygen, carbon. A compound is a body made up of two or more elements in definite pro- portions, e.g., carbonic acid gas. . An atom is the smallest conceivable subdivision of an element. A molecule is composed of two or more atoms; it is the smallest quantity of an element, or of a compound, that can exist in the free state. A compound radical is a compound body which acts like an element in form- ing compounds. Sometimes it may exist in the free state, e.g., cyanogen. In other cases it cannot exist free, e.g., ammonium ; it is then called a hypo- thetical radical. A symbol is a sign used to indicate the presence of an element. It is either the initial capital or the first and an additional small letter of the Latin name of the substance, e.g., Carbon, C; Chlorine, Cl. A formula is a collection of symbols which represents a molecule of any substance, e.g., HCI. An equation consists of symbols and formulae with the algebraic signs of + and It is used to indicate the results of the action of substances on each other. There must always be the same number of atoms of each ele- ment on each side of the = sign. CaCO3 + 2HCI = CaCl2 + H2O + CO2. Atomic weight is the weight of one atom of any element compared with the weight of an atom of hydrogen. H being one, O is sixteen, C twelve, N fourteen. Molecular weight is the sum of the weights of all the atoms comprising the molecule of a substance, e.g., H2O = 18, or C02 44. Valence and atomicity are terms used to express the combining power of INTRODUCTION. 4 one atom of an element as compared with that of an atom of hydrogen. It is indicated by one or more dashes attached to the symbol, e.g., Cl' is univa- lent; O'is divalent; N'" is tri valent; Civ is quadrivalent. Each of these elements unites respectively with one, two, three, and four of hydrogen. Inorganic and Organic Substances. 11. This form of subdivision may generally he shown by the use of dry heat. Subjected to a temperature of I,ooo° F., the great majority of inorganic bodies show little or no change in their color or condition; a few, like the compounds of arsenic, mercury, and ammonia, volatilize, but many of these recondense in their original state. Organic bodies, on the contrary, are, with few exceptions, decomposed by a heat under I,ooo° F., and since they contain carbon in considerable quantity, they leave a charred mass or resi- due of charcoal, which by a continued application of heat may be burned away. 12. The demonstration of these facts, and the subdivision of the two great groups is shown by the following experiments: Cleanse a slip of platinum foil by washing, and then ignite it in the Bunsen flame until it ceases to color the flame yellow. First.—Place on the foil a piece of chalk, CaCo3, the size of a large pin’s head, and heat in the flame to a bright red. It neither blackens nor volatilizes, and thereby affords an example of a non-volatile inorganic body. Second.—Cleanse the foil, and repeat the experiment, using a similar piece of ammonium chloride, NH4CI. It disappears or volatilizes without change of color. If the experiment is re- peated in a dry test-tube, the NH4CI deposits on the wall of the tube. This is called a sublimate, and furnishes an example of a volatile inorganic body. Third.—Cleanse the foil, and repeat the experiment, using a similar piece of starch, C 6H100,,. On being immersed in the flame, it catches fire and burns without the odor of burning hair ; black residue of C remains, which may be entirely consumed. Here we have a non-nitrogenized organic body. Fourth.—Cleanse the foil, and repeat the experiment, using a cutting from a finger-nail. Again the substance burns and blackens, but in addition it gives the odor of burning hair, since it is a nitrogenized body. Fifth.—When organic bodies show cellular or other tissue-like structure under the microscope, they are said to be organized. This distinction is an important one, since a vast number of organic bodies have been artificially made in the laboratory, while no organized structure ever has, and probably never will be, artificially made. Base. Acid. Salt. 13. A base or a metallic hydrate is formed by the substitution of a metal in place of one of the atoms in water. 3H20 + K,= 3KHO + H,. INTRODUCTION. 5 The equation shows the action of potassium on water, potassium hydrate being produced and hydrogen set free. Bases which are soluble in water, as KHO and NaHO, are called alkalies. They turn red litmus blue. An acid is a hydrogen compound which, in contact with a metallic hy- drate, forms water, and the metal of the hydrate takes the place of the hydrogen in the acid. hno3+kho=h2o+knos. Many acids are sour to the taste, and turn blue litmus red. A salt is an acid in which the hydrogen has been replaced by one or more metals or compound radicals. REACTION 14. Is a term used to indicate the action of bases, acids, and salts upon red and blue litmus. It may he either alkaline, acid, or neutral. The most convenient form in which litmus can be employed is that of stained paper, to he prepared as follows : In a test-tube place f 3 ij, of water, add half a dozen cubes of litmus, and boil the mixture for a couple of minutes. The re- sult is a decoction of litmus (article 4, third). Decant and filter the solution (article 5) into a clean test-tube. Pour a portion of the filtrate into a clean watch-glass, pass through the fluid slips of filtering paper about one inch in width and a foot in length. As fast as the paper is soaked in the decoction, hang the slips up to dry. Fold the papers and preserve them between the leaves of a book. This is the blue litmus, and serves to detect an acid reaction by changing color to red. Place in a clean dry watch-glass about gtt. v. of HCI. Warm the glass gently over the Bunsen flame, and when white fumes arise, take one of the slips of blue paper and pass it through the acid fumes about one inch above the watch-glass until it turns red. It is now in condition for the detection of an alkaline re- action, the blue color being restored by liquids possessing that condition. If both blue and red litmus are unchanged by the fluid, the reaction is neutral. DIVISIONS OF THE COURSE. 15. Section First.—Poisons, their manner of action, or tests and their chemical antidotes. Section Second.—Water and its impurities. Section Third.-—Animal fluids. Section Fourth.—Sediments and calculi. Following this plan, we shall first take up the examination of poisons and their tests. The student will thus gain that experience in manipulation which is so necessary for the proper examination of urine and other com- plex fluids. SECTION I. POISONS. 16. The law does not define the term, but in common language a poison is said to be “ anything capable of destroying life when taken in small quantity.” For the purposes of the medical jurist this is not sufficiently exact. Wormley defines a poison as “a substance which, when introduced into the body and being absorbed, or by its direct chemical action, or when ap- plied externally and entering the circulation, is capable of producing dele- terious effects.” Letheby says: “It is anything which otherwise than by the agency of heat or electricity is capable of destroying life, either by chemical action on the tissues of the living body, or by physiological action from absorption into the living system.” “To sustain a capital charge it is necessary to prove that the substance administered is a poison or other destructive thing, given with intent to commit murder. ” A poison must be a destructive thing, but a destructive thing is not necessarily a poison. A destructive thing may act mechani- cally, as in the case of needles and fine-chipped horsehair. PHYSIOLOGICAL DIVISIONS. 17. According to their physiological action poisons are divided into cor- rosive, irritant, and neurotic. Examples of the first group are found among the strong mineral acids and caustic alkalies ; of the second, among various metallic salts, and of the third, among such substances as morphia, strych- nia, and other alkaloids. It often happens that the action of a poison varies with the dose ; strong HjSOi is a corrosive ; if dilute, an irritant. So oxalic acid may act either as an irritant or as a neurotic, according to the dose. CHEMICAL DIVISIONS. 18. As in the case of other substances, poisons may be divided into in- organic and organic. The former of these includes the so-called metallic poisons, many acids, and the alkalies. The latter deals with certain vege- table substances, as opium, the active principles of which are called alka- loids. Certain highly noxious animal secretions may be added to this group, but we shall not have space for their consideration. INORGANIC POISONS. PURIFICATION. 19. In the tests given for the different poisons it is understood that the substance is comparatively pure ; but if it is necessary to search for it in articles of food or in vomited matter, it must be separated as completely as possible from insoluble matters by straining and filtering. If it is mixed with soluble albuminoid material, the process of dialysis must be resorted to. For a description of this the student is referred to any modern chemi- cal text-book. INORGANIC POISONS. Arsenic. As and v = 75. PREPARATIONS IN ORDINARY USE. 20. First.—Elementary, commonly called metallic arsenic, has a steel- gray lustre. Mixed with oxide it is black; it is used as an insecticide for flies; it unites with other metals, forming fusible, brittle, hard alloys. Is poisonous, probably by conversion into oxide. Second.—Arsenious oxide, As203; white arsenic, ratsbane, arsenious anhy- dride, is white, odorless, and nearly tasteless; is more frequently used than any other poison ; is also used by women as a cosmetic; and in medicine. The vitreous kind more soluble than porcelainous. As203 is about 40 times more soluble when boiled in water for one hour than when treated with cold water for same time. 1,000 grains of cold water dissolve less than 2 grains arsenious oxide in 24 hours. Solution in water is arsenious acid, or hydro- gen arsenite, As203 + 3H20 = 2H3As03. Where the insoluble compounds of arsenic act as poisons it is generally owing to the formation or presence of H3As03. The arsenites are used in medicine, and in calico printing. Third.—Arsenic oxide As 206, produced by strongly heating arsenic acid, ERAsO*. Arsenic acid is formed by action of HN03 on As 203, is used in forming magenta dye. Arsenious iodide, Asia, with mercuric iodide, llgl2, forms Donovan’s solution. Fourth.—Realgar, As S2, or red algar, and orpiment, As2S3, or the golden pigment, are used as paints. Fifth.—Liquor potassii arsenitis, or Fowler’s solution, is formed by boil- ing As203 in water containing K2C03, and coloring with comp, tinct. laven- der. It contains 4 grains arsenic to the ounce. Long boiling in strong solu- tion is required to prepare it properly. Sixth.—Paris-green, or Scheele’s green, is an arsenite of copper Cu"HAsO3. Schweinfurth’s green is a mixture of arsenite and acetate of copper. Both are used as pigments. Paris-green also used as a domestic insecticide. INORGANIC POISONS. 8 GENERAL TESTS. 21. First.—Draw sublimation-tubes 3 inches x in diameter. Second.—Sublimation test. Heat minute portion of As,03 in tube. Verify diamond-like reflection of crystals of the sublimate in sunshine. Third.—Heat small portion of metallic As in tube. Note that sublimate is in zones, that nearest heat is steel gray ; above that black ; above that dirty gray. From a very minute portion of As, a brown and even yellow sublimate may be obtained, as in certain forms of Marsh’s test. Fourth.—Oxidation test. Heat As sublimate in tube after breaking lower end, hold tube inclined at an angle of 45° in flame. Crystalline sublimate of As.,03 forms. To break tube, heat pointed end in flame, and then touch it to a drop of water, when it fissures and an opening is easily made. Fifth.—Deduction test. Place minute quantity of As203 in tube, and above it a chip of dry charcoal. Apply the flame to charcoal region of tube first, and then to the As203 ; the latter as it passes hot charcoal is reduced, and black sublimate of As is obtained. Sixth.—Oxidize this sublimate as in test fourth. Seventh.—Reduce As2S3 by potassium ferrocyanide, mingling them together dry, place in sublimation-tube, heat; black arsenic ring forms. Eighth.—Examine Paris-green by sublimation test. Heat in Sublimation-Tube. HCI and H2S Test. 22. Take f| j. of water in a small flask ; add two grains of Aso03, and boil for five minutes ; a portion dissolves ; H3As03 arsenious acid forming. Keep this solution until arsenic exami- nation is finished. First.—In a large test-tube place water to a depth of one inch ; add f3j. of solution H,AsO3. To this add gtt. xx. of HCI; no visible effect is produced. Second.—Pass H,,S gas through the mixture, or fill the tube nearly full with strong H,,S solution ; a yellow precipitate of As,,S3 forms. Third.—Warm the contents of the tube, and, closing its mouth, agitate it violently to promote the separation of the precipitate from the fluid. Fourth.—Collect the precipitate upon a filter and wash with warm water. INORGANIC POISONS. 9 Fifth.—With a glass rod place a small portion of the moist precipitate in each of three watch-glasses. Sixth.—Examine contents of one watch-glass with KH4HS ; it dissolves. Seventh.—Examine contents of second glass with NHtHO ; it dissolves. Eighth.—Examine contents of third glass with strong HCI ; it does not dissolve. Ninth.—Mix a little of the dried precipitate As„S3 with two or three times its bulk of potassium cyanide ; note the odor of the cyanide. Heat from above downward in a sublimation tube ; arsenic is reduced, a black metallic mirror forming. This examination of the precipitate from fourth to ninth is necessary to prove that it is an arsenic sulphide, since yellow pre- cipitates with H„S are given by other substances. Tenth.—ln a small test-tube place f 3 ss. of water, add gtt. xx, of solution H3AsO„, fill the tube nearly full with H„S solution ; a yellow color is produced, but no precipitate. Add to the mixture gtt. xv. of HCI; a precipitate forms. This shows the necessity of always adding HCI to the solution when it is to be examined by the H„S test. 23. NH4HS gives yellow color with arsenious solution, but no precipitate until HCI is added in excess, when As2S3 is thrown down. 24. Ammonio-sulphate-copper test.—In a small tube place f 3 ij., or about 7-|- cubic centimetres of water ; add gtt. three to five of dilute NH4HO ; treat the mixture with solution CuS04 until the precipitate ceases to dissolve. To the ammonio-sulphate thus pre- pared and containing a slight excess of cupric hydrate, Cu"2HO, add gtt. xx., or more, of solution H3As03 (22) ; a green precipitate, cupric arsenite, Cu'HAsO.,, is thrown down. Shake the mixture and pour one-half into another tube ; examine one portion with HN03 and the other with NH4HO ; the precipitate dissolves in both cases, giving a colorless solution in the first, and a blue solution in the second instance. SPECIAL TESTS. 25. Ammonio-nitrate-silver test.—To f3 j. of water in a test- tube add a crystal of AgN03 the size of a large pin’s head ; the test is then performed as in the preceding case, substituting this silver solution for that of cupric sulphate. The solution of AgN03 is added to the highly diluted NH,HO until the white precipitate of silver oxide ceases to dissolve. To this ammonio-nitrate of silver gtt. xx., or more, of H3As03 solution is added ; a canary- yellow precipitate of arsenite of silver, Ag3As03, forms. Divide INORGANIC POISONS. 10 the precipitate as in the ammonio-sulphate-copper test. Examine with NH4HO and HN03. It gives a colorless solution in each case. If any portion of precipitate fails to dissolve in HN03, it shows the presence of some chloride as an impurity. 26. Beinsch’s test.—Examine the purity of materials as follows: In a .small test-tube f 3 ij. of water and gtt. xx. of HCI, introduce two or three slips of copper foil; heat to boiling, and keep at 212° F. for five minutes, replacing the water as it evaporates. If the copper remains perfectly bright, the materials are sufficiently pure for ordinary testing. Add f 3 ss. of H3As03 (22) solution to 3 ij- of water in clean test-tube, introduce half dozen slips of Cu and gtt. xx. of HCI; boil as before. The arsenic deposits as a gray coating on the Cu ; as it thickens it becomes black. In this test other substances besides arsenic may deposit on the Cu. To prove that the coating is arsenical, rinse the Cu slips with water from washing bottle, dry gently by pressure between folds of bibulous paper, place in sublimation-tube, heat; arseni- cal coat gives a ring of As203 crystals on tube, and if the quantity is considerable and the tube very narrow, the black arsenic mirror may appear. Such As203 rings may be tested by the solution tests to demonstrate their nature. This test may be applied directly to organic mixtures contain- ing As203 ;as vomited matters, stomach contents, etc. In that case the materials should be digested with dilute HCI (IHCI to 6H„0) for an hour, or longer, on the water-bath. The solution obtained should then be boiled with Cu slips, and the deposit examined as before. 27. Marsh’s test consists in the conversion of the arsenic into arsenite of hydrogen and its examination. For the description of this test the student is referred to larger works. 28. As203 acts as a poison either by internal or external administration. The symptoms are usually those of an irritant; occasionally they are those of a neurotic. Where solutions have been taken they are sometimes almost immediate, generally they come on in from half an hour to an hour. Cases are related in which they have been deferred six, nine, ten, and sixteen hours. The smallest fatal dose administered internally was two grains.. Shortest period in which death has occurred is two hours; generally in from twelve to thirty-six hours. External application to ulcers, abrasions, eruptions, has caused death with- in thirty-six hours. One man poisoned two wives in succession by introduc- ing As203 into the vagina. Use of aniline dye into which arsenic enters, and of wall-papers colored with Paris-green have caused slow arsenical poisoning. TOXICOLOGY. INORGANIC POISONS. 11 ANTIDOTES. 29. The best are freshly prepared hydrated peroxide of iron, and dialysed iron. The hydrated peroxide or ferric hydrate may be prepared by adding the muriated tincture or perchloride of iron, Fe2Cl6, to an excess of solution of ammonia, the ferric hydrate, Fe26H0, is thrown down as a red gelatinous precipitate. The mixture is to be well agitated and filtered through cloth ; after the fluid has drained off, more water may be poured over the pre- cipitate to remove the excess of NH4HO. The moist magma may then be administered ad lib. Ferric hydrate acts by converting the soluble As 203 into an insoluble ferrous arseniate, according to the following equation ; 2Fe26HO + As 203=Fe32As04 + 5H20 + Fe2HO. Antimony, Stibium. Sb'" and v = 122. PREPARATIONS IN ORDINARY USE. 30. Various alloys, as type metal, pewter, Britannia metal. Sulphide, Sb 2S3, needle-like crystals, the powder used by women to pencil eyelids. Kermes mineral, antimonii oxysulphuretum, is a mixture of oxide with tri- and penta-sulphide. Tartar emetic, tartrate antimony and potassa, K(SbO)C J1i06.H20. Color- less or white crystals, rhombic octahedra, effloresce, odorless, nauseous metallic styptic taste. Soluble in fifteen of cold or two of hot H2O. In- soluble in alcohol. Antimonial wine is tartar emetic dissolved in sherry. GENERAL TESTS. By Heat in Sublimation-Tube and on Charcoal. 31. Tartar emetic heated in sublimation-tube blackens and gives empyreumatic odor. In the blowpipe flame fuses and oxi- dizes rapidly, giving white coating on the coal. 32. Dissolve 10 grs. of tartar emetic in f§ j. of water in a small flask, heating if necessary. Keep the solution till the tests are finished. HCI and H2S Test. First.—In a large test-tube place f 3 ij. of the solution of K (Sb 0)C 4H40 CH„O, add a drop or so of HCI; a white precipitate forms which dissolves in excess of HCI, and is reprecipitated by H2O. This is Sb„o3. Second. —Pass H2S gas through the above mixture, or fill the INORGANIC POISONS, 12 tube nearly full with strong H2S solution, Sb2S3 is thrown down as an orange-red precipitate. Third, fourth, fifth, sixth to be conducted as in the case of arsenic. The precipitate dissolves in NH4HS (22.6). Seventh.—The precipitate does not dissolve in NH,HO (22.7). Eighth.—lt does dissolve in HCI (22.8). The reactions of the antimony sulphide with NH4HS,NH4HO, and HCI serve to distinguish it from other reddish precipitates formed by H2S in acid solutions. From arsenious sulphide it is distinguished by its different action with NH4HO and HCI. SPECIAL TESTS, 33. Ammonio-sulphate-copper, and ammonio-nitrate-silver do not act as in case of H3As03 (24 and 25). 34. Beinsch’s test.— Conduct in the same manner as for arsenic, omitting the purity test, since the materials have already been examined in study of As. Use f. 3j. of the solution of tartar emetic. The deposit on the Cu may be bluish-black, purple, or violet (26). On heating the Avashed and dried Cu slips with their deposit in the sublimation tube, the sublimate is generally amorphous or non-crvstalline, and closer to the Cu slips than in the case of As,o. (26). 35. Marsh's test. In some respects tartar emetic shows similar reactions to those offered by H3As03, but in others it is radically different, and is, therefore, easily distinguished therefrom. The student is referred to chemi- cal text-books. 36. In large dose the antimony poisons conform to the irritant group. The smallest fatal doses of tartar emetic recorded are: in a child, three- fourths of a grain; in an adult, two grains. These are exceptional; ten grains is generally regarded a poisonous dose. Time of death varies. Three-fourths of a grain administered to a child caused death in one hour. In a lady twenty-one years of age death occurred in seven hours. TOXICOLOGY. Slow poisoning by tartar emetic formerly quite common. Small doses were given from time to time, and the condition of the gastric mucous mem- brane so perverted, that death finally ensued from apparently natural causes. By alternating small doses of tartar emetic with small doses arsenious oxide, the poisoner often succeeded in completely avoiding detection. ANTIDOTES. 37. When there is no vomiting, use stomach-pump. Strong infusions and decoctions of vegetable astringents, as cinchona, oak-bark, green tea, are recommended as chemical antidotes. Their manner of action is not evident, and their usefulness is denied by some. INORGANIC POISONS. 13 Mercury, or Quicksilver, Hydrargyrum. Hg'and " = 200. 38. The metal, silver-white fluid, boils 662° F., solidifies 39° F. The alloys of Hg with other metals called amalgams, are used in making mirrors. Hydrarg. cum creta., blue pill, mass hydrarg., and ung. hydrarg. contain Hg very finely subdivided. Two series of Hg compounds ; the sub, or ous are mild, and the per, or ic are energetic poisons. PREPARATIONS IN ORDINARY USE. i, or ous are mild, and the per, or ic ous Series. Mercurous oxide, Hg,o, black. Mercurous sulphide, IlgoS, black. Mercurous chloride, HgCl, calomel. Mercurous iodide, Hgl, green. ic Series. Mercuric oxide, HgO, yellow or red. Mercuric sulphide, HgS, cinnabar and vermilion. Mercuric chloride, HgCb, corrosive sublimate. Mercuric iodide, Hgl2, red. Mercur-ammonium chloride, NHoHgCI, is white precipitate. GENERAL TESTS. By Heat in Sublimation-tube 39. ous Series, use calomel Sublimes without fusion, yel- low hot, white cold (21 j. ic Series, use corrosive subli- mate. Fuses, then sublimes, yellow hot, white cold. HCI and H2S Test. 40. Calomel HgCl is not sol- uble in H2O. 3j. may be sus- pended in f 3 j. of H.,0 by agi- tation. Shake the mixture each time it is used. First.—Place f 3 ij. of the mixture in a large test-tube, add gtt. v. of HCI, no action. Second.—-H,S in above mix- ture gives black precipitate, Hg2S, which forms immediately. Prepare solution, 10 grs. Hg Cl2 to f§ j. of HaO. First.—Place f 3 ij- of the so- lution in large test-tube, add gtt. v. of HCI, no action. Second.—H,S gives a light colored, then brown, then black precipitate of HgS, which turns red when dried and strongly heated. Third.—Collected on a filter, washed, and treated with strong HNOa in a watch-glass, these black sulphides of mercury are not dissolved. They dissolve in a mixture of HCI and HN03, or aqua regia. INORGANIC POISONS. 14 SPECIAL TESTS 41. Act differently, according as it is an ous or ic salt. ous Series. For each test, use f 3 j- of the mixture. Aq. calcis, gives black wash, Hg„°. KHO, gives black oxide, Hg.,o. NH,HO, gives black oxide Hg20. ic Series. For each test, use f 3 ss. of the solution. Acp calcis, gives yellow wash, HgO. KHO, gives red oxide, HgO. NH4HO, gives white mercur. amm. chloride. 42. For corrosive sublimate, bichloride, or perchloride of mer- cury, the following additional tests may be used, employing f 3 ss. of the HgCl, solution for each. AT solution gives a yellow to red precipitate ; add it very carefully. The precipitate is soluble either in HgCl., solution or in KI solution. Prepare the KI solution by dissolving a crystal of KI, the size of a pepper corn, in f 3 j. of water. Albumen, gives a white, tolerably insoluble compound. 43. Beinsch’s test is to be performed in the same way as for H.AsO.,. The coating on the Cu may be silver-like or gray. On heating the washed and dried slips in sublimation-tube a gray sublimate of minute mercurial globules may be obtained; rubbed with a wire or splinter of wood these coalesce and form a large globule of Hg. 44. Galvanic test.—Place a drop of HgCl2 solution on a gold surface ; touch the gold through the drop with a steel knife-blade. Hg deposits on gold as a silver-like stain ; it may be polished. This test is useful to detect presence of bichloride in calomel. 45. The majority of cases arise from the use of corrosive sublimate, which acts as an active irritant poison when administered in sufficient quantity, either internally or externally. Inhalations of Hg vapors and the applica- tion of mercurial preparations to the skin produce slow or chronic poisoning. Vermilion HgS is stated by some to he poisonous, but this is denied by others. Smallest fatal dose recorded for an adult was six grains of corrosive subli- mate. A woman recovered after taking one ounce. Shortest fatal period was half an hour in the case of a man. Death has oc- curred on the sixteenth day. TOXICOLOGY. ANTIDOTES. 46. In acute poisoning the immediate administration of albumen, best obtained from white of egg, is the safest antidote. A precipitate is produced which will dissolve slowly in gastric juice, therefore the stomach-pump INORGANIC POISONS. 15 should be used to remove it, and more albumen administered, In chronic poisoning KI is used. Lead, Plumbum. Pb " and iv 207. PREPARATIONS IN ORDINARY USE. 47. The metal was dedicated to Saturn by the ancients, hence ‘ ‘ Satur- nine poisoning; ” it is used for lining water-cisterns and for water-pipes. Pb dissolves in H2O containing H2COs, a,carbonate being formed. Lead enters into the composition of many alloys, as pewter, Britannia metal, solder ; in shot it is alloyed with As. Litharge, or massicot, FbO, used as a paint, boiled with olive-oil forms the oleate of lead, or emplastrum plumbi. Minium Pb^o4, or red lead is the ordinary red paint. Carbonate of lead, FbCOr, is the ordinary white lead paint, used also as the vehicle for other colored paints; it is employed by gas-fitters to make gas-tight joints. Dissolves completely in HNOa; thus mixture with barium sulphate may be detected, the latter not dissolving in HNO3. Chrome yellow, PbCrCh, chromate of lead, is the ordinary yellow paint. By boiling this with lime and water, orange chrome is produced. Sugar of lead, or acetate, Pb2C2H3O2, is crystalline, with sweet, astringent taste, used in medicine externally and internally ; also in certain sugar re- fining operations. Goulard’s extract, or subacetate of lead, also used in medicine. GENERAL TESTS Heat in Sublimation-Tube and on Charcoal. 48. Pb2C2H302 heated in test-tube blackens and gives off odor; other compounds than the acetates mentioned do not give odor ; some of them change color. Heated on charcoal in the blow-pipe flame, lead compounds give a bead of metallic lead, surrounded by a yellow ring of litharge, PbO, 49. Dissolve ten grains of the acetate, or of the nitrate of lead, in f | j. of H.,0, and keep the solution till tests are finished. First.—Place f 3 ij. of the lead solution in a large test-tube, add a drop or so of HCI, a white precipitate of PbCl„ separates, which is soluble in 33 parts of H2O, Second.—Pass H„S gas through the acidulated mixture, or fill the tube nearly full with strong H2S solution, a dark brown pre- cipitate of PbS is thrown down. Third.—Collected on a filter, washed (22, Third and Fourth), and treated in watch-glass with strong HNO,, and heat, the black sulphide, PbS, is converted into a white sulphate, PbS04. HCI and H2S Test. INORGANIC POISONS. 16 SPECIAL TESTS 50. Use f 3 j • of the lead solution for each test. First.—Prepare a KI solution, as in testing- for mercury (42) ; it gives a satin yellow Phi , slightly soluble in H„0. Boil with H„0, filter hot ; on cooling, beautiful golden scale-like crystals deposit. Second.—H2S04 gives white PbS04. In very dilute solution, as a lemonade, H2S04 is a preventive against chronic lead-poison- ing in workmen. Soluble sulphates also precipitate the Pb as PbS04. Third.—Prepare Iv,2Cr04 solution as in case of KI (42) ; it gives chrome-yellow PbCr04. TOXICOLOGY. 51. Acute poisoning is rare, and nearly always by tlie acetate ; wlien it happens, the lead compound acts as an irritant. Dose one to three grains, every two or three hours, has produced poison- ing symptoms. A drachm dose was nearly fatal; an ounce dose has been taken without serious result. Chronic poisoning is common in painters, plumbers, and other workers in lead, and with its compounds. Common red rubber plates for artificial teeth have produced evil results. Slow lead-poisoning also occurs by the metal dissolving in H2O from the tanks and pipes in which it is kept or conveyed. A much greater portion of the metal is dissolved by rain than by spring waters which contain sulphates (50, Second). To examine water for lead, evaporate a large quantity to one-fiftieth of its volume in a small porcelain capsule, dropping small portions into the capsule from time to time. Treat with strong HNOs ; evaporate to dryness ; dissolve residue in water ; filter ; treat portions of filtrate with ILS and other tests. Be sure that the lead found does not come from the glaze on the capsule. ANTIDOTES. 52. For acute poisoning, stomach-pump, and solution sulphate of magne- sia, or of sulphate of soda. As a prophylactic in lead-works, sulphuric acid lemonade. In chronic poisoning, in which it acts as a cumulative poison, lead may be eliminated from the system by the internal administration of iodide of po- tassium. Lead may be found in the urine after the treatment is well under way. Copper, Cuprum. Cu ' and " = 63.5, 53. The metal was dedicated to Venus by the ancients. Together with its alloy, brass, it is used in making culinary vessels. Small traces of Crx are found in the human body. Cupric oxide, CuO, is black. Cuprous oxide, Cu>o> is red ; both are of importance in testing for diabetic sugar, and in organic analysis. PREPARATIONS IN ORDINARY USB. INORGANIC POISONS. 17 Pyrites, CuS, is a common brass-like ore. When freshly precipitated CuS is black. CuCO3 is the greenish crust which forms on copper vessels when exposed to damp air. The green paint Verditer contains this substance. Blue vitriol, cupric sulphate, is in common use for many purposes. Cupric arsenite, or Paris-green (20, Sixth), is in common use as an in- secticide ; is often used by suicides. Cupric acetate, Cu2C.iH3Cb, is green. Verdigris is a subacetate. Bruns- wick-green and Schweinfurth-green are mixtures of arsenite, acetate, and carbonate of copper. Heat in Sublimation-Tube and on Charcoai GENERAL TESTS. 54. First.—Blue vitriol heated in the tube turns white and gives off its H,O. Paris-green gives crystalline sublimate of As2°3. Second.—Cu compounds, if powdered, moistened in a watch- glass with HCI, and introduced on fine glass rod, or on iron- wire into a Bunsen or a spirit-flame, give to it green and blue tints. Third.—Some compounds mixed with Na.,C03 give a bead of red metallic copper when heated on charcoal in blow-pipe flame. 55. Use the saturated solution of CuS045H„0. First.—Place f 3 ij. of water in a large test-tube, add gtt. x. of copper solution, to this gtt. v. of HCI; no reaction except slight change in tint. Second. —Pass H„S through the acid mixture, or add H2S solu- tion ; a brownish-black precipitate falls. Third.—Collected on filter, washed and treated while moist in a watch-glass with strong HNO., and heat, the black sulphide CuS dissolves, the blue CuS045H,,0 being formed. HCI and H,S Tests. SPECIAL TESTS. 56. In a small test-tube f3j. of H2O, and gtt. x. of Cu solu- tion, mix, add NH4HO by drops very slowly, the pale blue cupric hydrate Cu2HO is thrown down ; it dissolves readily in excess of NH4HO, forming a blue or purple solution ; is known as am- monio-sulphate of copper. 57. In a small test-tube f 3 j. of H.,0, and gtt. v. of Cu solution, to this add gtt. xx, of KHO, sp. gr. 1,050. The pale blue cupric hydrate is thrown down ; it does not dissolve in excess of KHO. On boiling the mixture, if the KHO is in sufficient excess, the INOEG-ANIC POISONS. 18 olue hydrate is converted into the black oxide, as shown in fol- lowing equation: Cu2HO + heat=CuO + HaO- To prove the necessity of excess of KHO, repeat the operation, using only two or three drops of KHO instead of twenty. On boiling, the precipitate remains blue. Since KHO solution absorbs C02 from the air, it is converted into a carbonate, and fails to act. When this happens, more than gtt. xx. must be used, and if necessary, a fresh solution of KHO prepared. Care in proving that enough KHO is always added to produce the black CuO on boiling, makes this test perfectly reliable in the deoxidation test which follows. 58. Deoxidation test.—Take an eighth of an inch cube of grape- sugar, dissolve in f 3 ij- of H,O in a test-tube. Note how slowly it dissolves. Keep the solution. First.—Prepare a dilute solution of the above, gtt. x. to f 3 j< of water. Add gtt. v. of Cu solution, then add KHO, potassic hydrate very slowly. The first drop or so gives the pale blue Cu2HO, which dissolves as the remainder of the gtt. xx. is added, giving a purplish solution. On boiling this a yellow to red pre- cipitate of sub-oxide of copper Cu„o is produced, instead of the black CuO. Second.—Rcjoeat the experiment, using only gtt. iii. to v. of KHO. The cuprous oxide Cu.,o is not formed, thereby showing the necessity for the use of an excess of KHO. Third.—Prepare a very dilute solution of sugar, one drop to f 3 iv. of water, and use f 3 j. of this ; test it with gtt. v. of cupric sulphate and gtt. xx. of potassic hydrate. On boiling, though a little of the red Cu.,o may be precipitated, it is not seen, since it is masked by the large amount of black CuO present. Fourth.—Pepeat the experiment, using only a single drop of the cupric sulphate solution. A very faint reddish precipitate will appear if the reagents are properly adjusted in quantity. From this it is seen, that before it is decided that sugar is not present in a sample of urine it must be tested with a very small quantity of copper solution to find small traces. Fifth.—Prepare a solution of cane-sugar similar to that of grape-sugar, and test it in the same manner It does not throw down the red Cu„o, since it does not possess the deoxidation or reduction power of grape-sugar. s«>. Fehling’s solution affords a convenient method of applying the copper test for the quantitative determination of sugar. It is prepared as follows : Dissolve 34.64 grammes of pure crystal- INORGANIC POISONS, 19 lized cupric sulphate in 200 cubic centimetres of distilled water; dissolve 80 grammes of sodium hydrate in GOO c.c. of water, and add 178 grammes of Rochelle salt (sodium and potassium tartrate). Mix the two solutions, agitate thoroughly, and make up to one litre. Preserve in well-stoppered bottles, or in sealed tubes. One c.c. is exactly precipitated by 5 milligrammes of glucose, or grape-sugar. Pour 5 c.c. into a test-tube, heat to boiling, add the suspected sugar solution gradually by drops. If glucose is present, the blue tint changes to green, and the yellow or red cuprous oxide is precipitated. When the blue color is entirely discharged, the whole of the copper is precipitated. 60, Ferrocyanide test. To f3 j. of water add a crystal of prussiate or ferrocyanide of potassium the size of a pin’s head. To this solution add a drop or so of the copper solution. A chocolate-brown precipitate of ferrocyanide of potassium forms. Albumen solution gives a precipitate with solution of cupric sulphate. Iron or steel a knife-blade or a needle—dipped into a solu- tion containing Cu, shows a red coating of metallic copper on its surface in a short time. TOXICOLOGY. 61. Copper compounds belong to the irritant poisons ; tlieir criminal use is rare. Half an ounce of CuSO,SH2O killed a woman in sixty hours; 3 ij. was nearly fatal; §j. has failed to he fatal. Poison cases by Cu generally arise from its introduction into articles of food from copper or brass vessels in which it has been cooked. Especially is this the case if acids, oils, or fats have been used in the cooking. All pickles, preserves, vegetables, as string- beans and candied fruits of a bright green tint, are to be regarded with sus- picion, since the color is generally produced by the presence of copper. In the case of pickles, this may often be shown by piercing them with a needle and leaving it in situ for some time ; on being withdrawn it shows a copper coating. In making bread from damaged flour, cupric sulphate is often introduced into the dough to improve the whiteness of the bread. The use of copper in quantity as an inferior gold alloy for teeth-plates has produced evil results The shortest fatal period recorded is four hours, in a child of sixteen months old, from cupric sulphate Sour-krout from a copper vessel killed a young woman in twelve and her mother in thirteen hours. Three and nine days are also recorded. 62. Albumen and demulcents followed by stomach-pump. Iron filings and iron by hydrogen are also recommended. In the latter case the cop- per is reduced to the metallic state. ANTIDOTES. INORGANIC POISONS. Substances. Solid. Tests for Solutions. Heat in Tube. HCl. HaS. Other Tests. 1. Arsenic, arsenious oxide. * Sublimes crystals Yellow, sol. in NH-iHO ; insol. in HOI. Eeinsch—(Cu + HCl) gray to black deposit on Cu. Sublimes in heated tube, As203 crystals at distance from Cu. Antidotes, hydrated perox. iron, dialyzed iron. 2. Antimony, tartar Blackens. White, sol. in Orange, sol. in Eeinsch—(Cu + HCl) violet deposit on Cu. emetic. excess. HCl; insol. in NH-tHO. Sublimes in tube. Amorphous, close to Cu. Antidotes, decoction of oak-bark, tea or other astringents, stomach-pump. 3. Mercury, chlorides.. Sublime. Black, insol. in HNO,. Eeinsch—(Cu + HCl) gray or silver deposit on Cu. Sublimes in tube as minute drops, which unite if rubbed. Galvanic test; lime-water test ; KI test. Antidote, albumen and stomach-pump. 4. Lead, acetate Blackens. White if strong. Black, whitened by HN03. (NH4HO) white, insol. in excess. KI yel- low precipitate, satin-like reflection. An- tidote, acute — magnesium sulphate ; chronic—pot. iod. (KI). 5. Silver, nitrate ' Fuses. White, curdy, soluble in NHiHO. Black, sol. in hno3. (NH4HO) pale white, sol. in excess. KI pale yellow. Phos. soda, pale yellow, sol. in HNOa and NH4HO. Antidote, f solu- tion of salt, NaCl. 6. Copper sulphate.... Whitens. Black, sol. in hno3. (NHiHO) pale blue precipitate ; purple so- lution with excess. Pot. ferrocyanide, chocolate. Metallic Cu precipitated by Fe. Antidotes, albumen and stomach- pump, iron filings, iron by hydrogen. * Heated with carb. soda in tube, black sublimate. t In u,-ing AgN03 as a local application, it is well to neutralize any excess by applying weak solution of NaCl to the part. 63. EXAMINATION FOR METALLIC POISONS—SUBSTANCE UNKNOWN. INORGANIC POISONS. 21 Phosphorus. P'" an. Use the stomach-pump as soon as possible. Wash out the stomach with infusion of coffee or of green tea in which charcoal powder is sus- pended. Encourage vomiting by tickling throat; emetics. ANTIDOTES. Strychnia. 91. The alkaloid, its salts, and the preparations of nux vomica. Em- ployed in medicine and in various vermin-killers. It possesses a remark- able power of resisting decomposition by cold concentrated mineral acids and alkalies. Fermentation and putrefaction also have little effect upon it. Of the salts the acetate is the most soluble. TESTS. 92. Strychnia and its salts possess an intense, peculiar bitter taste. Place a small crystal on a slip of glass (microscope slide), and the glass on white paper ; with a fine glass rod cover it with strong H2S04 ; it dissolves without change of color. Alongside place a small crystal of potassium bichromate, and with another glass rod cover it with strong H2S04. After the acid has acted for a minute or so, draw the solutions together with one of the rods, when a blue color is produced which quickly turns to violet, then to red, and finally fades away. Marshall Hall’s test. Injected as a solution under the skin of a frog’s back, even in very minute quantity, strychnia and its salts quickly produce violent tetanus. This condition may also be brought on in these creatures by the action of warm water, a fact which must be taken into consideration when employing them as a physiological test for strychnia. TOXICOLOGY. 93. Strychnia causes the most intense muscular contractions, one especial feature being lockjaw. The patient dies either by asphyxia during one of the paroxysms or by exhaustion during a remission. One-sixth of a grain is regarded as a fatal dose. Severe tetanus has been produced by one-twelfth of a grain. One grain is generally given as the poisonous quantity ; on the other hand, a dose of twenty grains has been followed by recovery. The symptoms may come on immediately ; three and five minutes are also recorded ; generally they appear in from ten to twenty minutes ; they have been delayed an hour and longer. If the patient Survives five or six hours, recovery is almost assured. ORGANIC POISONS. 30 ANTIDOTES. 94. First.—Administer chloroform by inhalation to prevent lockjaw and enable you to use stomach-pump. Keep patient under influence for some time to moderate contractions. Second.—Empty stomach as quickly as possible with stomach-pump, and wash it out two or three times at intervals of five minutes with water con- taining charcoal powder in suspension. Use of opium, morphia, and camphor, and inhalation of oxygen are recom- mended. 95. The brief review we have given of the leading poisons will enable the student to master the various methods of manipulation required in test- ing for the presence of these bodies, at least for the purposes of diagnosis. When extended medico-legal examinations are required, the physician should not attempt them, but see that they are referred to a proper chemi- cal expert. For those who desire a further examination of the subject, reference may be had to the following works; Taylor’s “Medical Jurisprudence,” Woodman and Tidy’s “Forensic Medicine,” Wormley’s “Micro-Chemistry of Poisons.” SECTION 11. WATER, H.O. 96. A copious supply of potable water is one of the most urgent of the demands of the system. The great solvent power of this agent, taken in connection with the sources from which our supplies are obtained, render it peculiarly liable to become contaminated with substances more or less dele- terious to the human economy. FOREIGN SUBSTANCES IN WATER. 97. First. Gaseous.-—All natural waters contain oxygen and nitrogen, derived from the air. AVater which, has been boiled, and its normal supply of free gas thus expelled, and distilled water possess an unpleasant taste. In addition to O and N, the water of certain localities contains small traces of ammonia, carbonic acid, hydrochloric acid, salt, organic and inorganic dust also derived from the air. The water of certain springs contains large proportions of carbonic acid gas and of sulphuretted hydrogen, derived from chemical changes taking place within the earth’s crust. Second. —Liquid.—Deleterious organic and inorganic liquids also find their way into our supplies of water; of these the most common is the sewage from house-sinks and waste materials from factories. Third.—Solid.—May be in suspension or solution ; they are either organic or inorganic. The organic may be non-nitrogenized, or nitrogenized. The latter of these is the most dangerous of all the ordinary ingredients of natural waters, especially when it is capable of producing ammonia. The inorganic sub- stances are chiefly silica, and different salts of potassium, sodium, calcium, magnesium, lithium, and iron. 98. Rain-water which falls during the latter part of a storm is the purest of natural waters, since it can only contain substances derived from the air. Water from melted snow and ice comes next in the scale of purity, since in the act of freezing under ordinary conditions water rejects the substances held in solution and crystallizes in a nearly pure condition. Spring-water contains substances derived from the earth as well as from the air. According as the source of water in the spring is deep or super- ficial, so will it be wholesome or deleterious. Superficial or surface-water SOURCES OP SUPPLY. WATEK. 32 sp rings contain more or less of organic matter.. In deep springs, on the con- trary, all organic matter has been oxidized by the action of air in the strata through which the water has passed. Such waters contain a greater per- centage of inorganic substances, but these are, as a rule, less deleterious than the organic. Wells may be connected either with underground flowing waters, or with stagnant accumulations; in the former instance the water is as pure as in springs, in the latter it is often exceedingly deleterious, especially is this the case when they are sunk in barnyards, in gardens, near privies, and sewers, or at a lower level than graveyards. The water from such sources is often a dilute solution of decaying humanity, or of the excreta of men and animals, and prone to favor the development of certain dangerous forms of fever. In pools and marshes, the water being stagnant, organic matter which finds its way into them is not destroyed. Such water presents conditions favorable for the development of varieties of vegetable and animal forms which are deleterious. In this way the larvse of various entozoa also find their way into the bodies of animals. These waters should never be used for drinking or cooking purposes. Lake and river waters, by their depth or by their movement, present con- ditions favorable for the destruction of organic matter. These are often very pure, and adapted for domestic use. Ocean water and mineral waters are especially rich in inorganic salts, the latter are extensively used for medicinal purposes. Water containing both organic and inorganic impurities may be beautifully clear and pellucid when freshly drawn. EXAMINATION FOR ORGANIC IMPURITIES IN SOLUTION. 99. First.—Fill a bottle half full with water, and closing its mouth with a cork agitate it violently for two or three minutes. If the air in the upper part of the bottle possesses an unpleasant odor the water is not suitable for drinking purposes. Second.—Water which has stood over night in a pitcher ox- other vessel, and then has a fetid odor is also unfit for use. Third.—Place a pint or so of the water in a clean saucepan, ox- evaporating dish, and concentrate it down to one ounce. Fill a tablespoon or a capsule with this, and evaporate to dryness. If the water gives off an unpleasant odor during the evapox-ation organic matter is present, and if this is derived fx-om sewage the odor is exceedingly offensive as dryness is approached. Incin- erate the contents of the spoon, and the ox-ganic matter is de- stroyed, leaving a cax-bon residue which may be burned away. The relative px-oportions of the first residue and of the final ash afford the means of estimating the quantity of organic material. The ash is to be examined according to 107. Fourth.—The permanganate test.—Place a measured portion of the concentx-ated water in a large test-tube, aixd the latter on a sheet of white paper. Add to the water one-sixth its bulk of stx-ong H.,S04. Fx-om a burette add solution of potassium per- WATER. 33 manganate of known strength. The solution is decolorized if nitrogenized organic matter is present. When the permanganate is no longer decolorized, as may be determined by looking down- Avard through the fluid at the white paper, the amount used is to be read off, whence the comparative proportion of organic matter in the water may be estimated. Fifth.—Test for nitrites.—These are found in wrater containing decomposing nitrogenized matter. Add to the concentrated water a few drops of dilute pure H S04, then a little weak solution of iodide of potassium, and, finally, some starch mucilage. The deep blue iodide of starch is at once formed if nitrites are present. Nitrates do not act in this manner. Sixth.—On adding Nessler’s reagent to water containing ex- ceedingly minute traces of ammonia, a yellow to a red coloration is produced. One part of ammonia in many millions of Avater may thus be detected. The reaction is as folloAVS: NH3 + 2HgI2 + 3KHO = NHg.,I + SKI + 3H20. Nessler's reagent. This is prepared by dissolving 30 or 40 grammes of KI in a little hot Avater, adding strong hot solution of mercuric chloride, till the red mercuric iodide ceases to redissolve by heat and stirring, dilute, filter, add 180 grammes of caustic potash, and make up to one litre with water; about 5 c.c. of strong solution of mercuric chloride are added, the liquid set aside till it becomes clear, Avhen it is decanted for use. 100. While perfectly pure water has little or no action upon the silicates, carbonates, and other constituents of the rocks forming the strata from which springs flow, we invariably find that such waters contain more or less of these ingredients. A few simple experiments will demonstrate how the dissolving of these substances takes place. First.—ln a test-tube place 3 ij- of water with gtt. x. of lime- water, or calcium hydrate Ca"2HO ; pass a few bubbles of car- bonic acid gas through the mixture, or add a little strong solution of the gas in water, H2C03, at once a white precipitate of calcium carbonate is thrown down, the reaction being: Ca2HO + H,CO3 - CaC03 + 2H20. Calcium hydrate -f- carbonic acid =; calcium carbonate -f- water. Second.—Pass more of the CO., gas through the mixture, or add more of the HCO,, the precipitate gradually dissolves, the solu- tion assuming a beautifully clear pellucid appearance, brighter than that of the purest water. We therefore find that calcium carbonate is soluble in water containing carbonic acid, and that INORGANIC IMPURITIES IN SOLUTION. WATER. 34 exceeding purity in appearance should lead us to suspect the presence of some compound of calcium. Third.—Boil the solution obtained above; carbonic acid is ex- pelled after a time, and the precipitate reappears. 101. All spring, well, lake, and river waters used for domestic purposes are derived originally from rain-water. In passing through the air the rain dissolves therefrom a certain portion of the C02 present. Thus the water passing into the earth is in a condition favorable for action upon the carbo- nates it contains. In like manner even the hardest silicates yield to water containing carbonic acid, and silica, one of the most insoluble of all sub- stances, is brought into solution. While rain itself contains carbonic acid, the quantity present is small compared with that produced in the water after it reaches the earth. In the superficial strata the water dissolves organic matter; in the deeper strata this is oxidized by the oxygen held in solution in the water, and so carbonic acid is produced in considerable amount. Hard and Soft Waters. 102. The presence of carbonates and sulphates of lime and magnesia give to water the property of producing a curdy precipitate with soap before a lather can he formed. Such waters are called hard, in contradistinction to rain-water and distilled water, which form a lather at once with soap. Hard waters are not well adapted for washing. They also form thick deposits on the interior of steam boilers, causing their tubes to burn away, and thereby lead to explosions. In the human economy, in like manner, they often lead to the production of calculi by the introduction of excess of inorganic material into the system. Water may be either temporarily or permanently hard. In the first in- stance the calcium compound is a carbonate held in solution by carbonic acid, which may be expelled by boiling, and the CaCO3 reprecipitated. In the second case it is a sulphate or some other form dissolved independently of the action of carbonic acid, and not reprecipitated by its expulsion. Claries soap test depends upon the formation of an insoluble lime soap, when a standard solution of soap in alcohol is brought in contact with water containing calcium compounds. The soap solution is added gradually from a burette to a known quantity of the water; the mixture is shaken after each addition until curd ceases to form, and a permanent lather is produced. The amount of soap solution used is read off, and the degree of hardness deter- mined. Inorganic Residue from Water. 103. For a more thorough knowledge of the character of the inorganic constituents of a water, the student must be acquainted with the following re- actions presented by silica, and also by potassium, sodium, and calcium compounds: 104. First.—Potassium reaction. Cleanse the platinum foil as in article 12. Place a small crystal of potassium chlorate in a WATER. 35 watch-glass, crush it to a powder, and moisten with a drop of HCI. Dip the foil into the mixture, and introduce it into the Bunsen flame, a momentary -violet tint appears. Repeat the ex- periment until the eye is accustomed to the reaction. Viewed through the spectroscope a violet and a red bar are seen in the spectrum of such potassium flames. 105. Second.—Sodium reaction. Cleanse the foil, and repeat the experiment with sodium chloride. The flame becomes yel- low, and through the spectroscope a yellow bar is seen. 106. Third.—Calcium reactions. Cleanse the foil, and place upon it a piece of chalk, CaC03, the size of a pin’s head. In the flame the chalk will be seen to shine with a phosphorescent light, which is quite independent of a red-hot temperature. This phenomenon also appears in the case of magnesium, zinc, and a few other metallic compounds. At first the calcium carbonate seems not to give a tint to the flame, but close inspection shows a faint yellowish red. After the chalk has been kept in an incandescent state for two or three minutes, place it when cool on a slip of red litmus papex’, and moisten it with water. The litmus will turn blue, showing an alkaline reaction. Place a little powdered chalk in a watch-glass, add a drop or so of HCI; a brisk effervescence is produced by the escape of carbonic acid gas. Dip the foil iixto this mixture, and on introducing it into the flame a bright red tint is seexx, which, being examined through the spectroscope, shows red and yellowish preen bands of calcium. 107.—Having become familiar with these x’eactions, apply them to the examination of the final ash obtained in article 99, Third. By the spectroscope the characteristic lines of potassium, sodium, and calcium may all be instantly detected if they are present. The undissolved residue left after the action consists almost entirely of silica, or silicic acid. Examination for HCI, and H„S04 acids contained in water must be conducted according to articles 69 and 70. For lead, see 51. PURIFICATION OF WATER. 108. When the impurity is in a condition of suspension, it may be re1- moved by filtration through layers of sand. Filters made of carbon may also be employed to advantage. Hard waters in which the calcium is present as a carbonate may he largely freed therefrom by boiling. If the water is permanently hard, boiling is of no avail. For the complete purification of water distillation must he resorted to. When such water is properly aerated, and a little common salt and solution of sulphate of lime and sulphate of soda added, it becomes very potable. SECTION 111. ANIMAL FLUIDS. 109. The fluids of the body consist of certain organic substances, and salts dissolved or held in suspension in water. So long as the relative pro- portions of these are normal the fluid possesses a certain specific gravity or density. Any departure from this indicates a change in normal proportions of the ingredients, or the appearance of some abnormal substance in the fluid. SPECIFIC GRAVITY. 110. For the determination of specific gravity the instrument called the hydrometer is used. According as it is graduated for the examination of alcohol, milk, urine, it is called an alcoho- meter, lactometer, urinometer. A good urinometer is all that is required for the purposes of the physician. In purchasing your urinometer, test it with water to determine whether the 0° of the scale is correctly placed. Avoid a very small instrument; select one graduated to single degrees. The divisions at the top of the scale should be farther apart than those at the bottom. Directions for Use of Hydrometer. Hold the reservoir obliquely when filling it, to avoid foam. Stand with your back to light or window. Hold the reservoir by the top to insure perpendicular position. Bring the top of the fluid to the level of the eye. Read the scale by the lower sharp edge of the fluid. Test your urinometer by the standard solutions of salt fur- nished for the purpose in the laboratory, and make a record of the errors found in different parts of the scale. Using these as cor- rections in future readings, a false urinometer may be made to serve as good a purpose as an accurate one. ANIMAL FLUIDS. 37 111. Temperature exerts an influence on the indications of the urino- meter. The following corrections should be made where accuracy is desired, as in the quantitative differential density test of sugar (173, Fouith). Temperature Corrections for Urinometer. Temperature. F. No. to be added to the indication. Temperature. F. No. to be added to the indication. Temnerature. F. No. to be added to the indication. 60° 0.00 69° 0.80 78° 1 70 61° 0.08 70° 0.90 79° 1.80 63° 0.16 71° 1.00 80° 1 90 63° 0.34 73° 1.10 81° 2.00 64° 0.83 78° - 1.30 82° 3.10 65° 0.40 74° 1.30 83° 3.20 66° 0.50 75° 1 40 84° 3.30 67° 0.60 76° 1 50 85° 3.40 68° 0.70 77° 1.60 86° 2.50 Proteids 112. These are nitrogenized, organic substances, which enter into the composition of all the tissues and fluids of the body, with the exception of healthy sweat, tears, bile, and urine. They are all amorphous, except hemoglobin, and soluble in strong acids and alkalies, with decomposition. Some dissolve in water, their solutions possessing left-handed polarization. Their composition, according to Hoppe-Seyler, varies O. H. N. C. S. from 30.9 6.9 15.3 51.5 0.3 to 33.5 7.8 17.0 54.5 3.0 TESTS. 113. First.—Heated in a watch-glass with strong HN03, the proteids become yellow ; the addition of NH4HO to this gives a deep orange tint. Second.—Treated with solution HNaO, and a drop or so of cupric sulphate solution in a test-tube, they give a violet color, which becomes darker on boiling. Third.—With Millon’s reagent they give a precipitate, which, with the fluid, turns red on being heated. If only traces of a proteid are present no precipitate forms with the test, but the fluid turns red on being heated. In this manner al- bumen may be detected in an aqueous solution. 114. Millon's reagent is prepared by heating to 180° C. one part of mer- cury with two parts of nitric, acid of sp. gr. 1.43. When the Hg is dissolved two volumes of water are added to one of the solution, and after standing for twenty-four hours the clear liquid is decanted and used for the test. The proteids which especially command our attention are albumen, casein, ANIMAL FLUIDS, 38 and fibrin. These are often called albuminous bodies; they present certain modifications to which the term albuminoid is applied. Albumen. 115. Two varieties of this substance are described, viz., egg-albumen and serum-albumen or serin. Egg-albumen may be prepared by breaking up the white of an egg, dilut- ing with equal hulk of water, and shaking in a flask till it is frothy; after resting, the froth rises and carries the fibres with it. The fluid is then strained, dilute acetic acid added as long as it causes a precipitate, and the mixture filtered; the filtrate is neutralized. Serum-albumen separates spontaneously from blood. It is the form which usually appears in the urine. TESTS. Similarities. 116. Egg -albumen. Coagulated at 73° C. Coagulated by strong HN03. Mercuric chloride precipitates does not coagulate. Lead acetate precipitates does not coagulate. Serum-albumen. Coagulated at 73° C. Coagulated by strong HN03. Mercuric chloride precipitates does not coagulate. Lead acetate precipitates does not coagulate. Differences, Rotation power over polarized light —35.5° for yellow light. Coagulated by ether. Precipitated by HCI; precipi- tate not readily soluble. When coagulated is not readily soluble in strong HN03. Injected into the veins, or un- der the skin, passes unchanged at once into the urine. Rotation power over polarized light —s6° for yellow light. Not coagulated by ether. Not so readily precipitated by HCI; precipitate dissolves readily. When coagulated is readily soluble in strong HN03. Injected into the veins, or un- der the skin, does not pass into the urine. 117. Either of these albumens treated with dilute acid, or with dilute alkali for a sufficient length of time, become converted into albuminates, known as acid-albumen and alkali-albumen respectively. In either of these conditions they are not coagulated by heat, but the whole of the proteid is thrown down when the solution is cautiously neutralized. Casein 118. In the pure state it is a white, friable, opaque substance. Soluble in dilute acids and alkalies, and reprecipitated on neutralization. Its reactions, therefore, resemble those of alkali-albumen. If potassium phosphate is ANIMAL FLUIDS. 39 present in the solution, as is the case with milk, it must be made strongly acid before the casein precipitates. Fibrin 119. Is insoluble in water. Soluble with difficulty in dilute acids and alkalies. It generally presents itself in the form of elastic filaments. If formed slowly in large masses, it loses the filamentous structure and re- sembles india-rubber. It imparts the property of spontaneous coagulation to blood and other fluids in which it is found. Milk 120. Is the secretion of the mammary gland. It is white in color. In some animals it has an acid reaction, hut in women it is alkaline. Average Composition of Milk. Woman. Cow. Water 889 865 Casein and extractive 40 55 Lactose or sugar 43 37 Butter or fat 27 86 Salts 2 7 1,000 1,000 The larger proportion of casein and fat in cow’s milk, and the smaller proportion of sugar, shows the necessity for the addition of water and sugar to make it a suitable diet for infants. The specific gravity of normal cow’s milk lies between 1,039 and 1,084. The removal of the fat causes a rise in the gravity. A rich specimen of freshly drawn milk with a gravity of 1,039 will show a gravity of 1,088 when the cream has been separated. By the addition of water the gravity may again be brought to 1,039, and thus the milk be made to appear as rich as at first; consequently, the lactometer alone is not a reliable test for the rich- ness of milk. 121, Condensed milk offers a fair substitute for fresh milk when the lat- ter cannot be obtained. It is prepared by adding white sugar to milk in the proportion of one ounce to the pint; the fluid is then concentrated to one-fifth in vacuum pans, and preserved in sealed cans. When opened, the contents of the cans keep better if a little is removed each day from the top. When used as a substitute for cow’s milk, it should be diluted with four times its volume of water. For infants, this should be still further di- luted, as in the case of cow’s milk. SPONTANEOUS CHANGES IN MILK. 122. Shortly after it is drawn from the gland the fat of milk separates spontaneously, and rises to the surface, forming cream. The reaction shortly afterward becomes acid, a portion of the sugar being converted into lactic acid by the splitting of its molecule. C,sHS4Oia = 4(H2CjH4Os). ANIMAL FLUIDS. 40 The casein is then coagulated and forms the curd, which rests in a tawny fluid called the whey, which consists of the water, salts, and remainder of the sugar of the milk. Lactic acid does not coagulate milk when cold, unless present in consider- able quantity. Aided by heat, it coagulates the casein easily, as do other strong acids. The sugar of milk, or lactose, acts toward the copper, or Trommer’s test, in the same manner as grape-sugar, reducing the black to the red oxide. TESTS. 123. Though the character of a specimen of milk can only be accurately determined by a troublesome and complete analysis, a proximate estimate of its richness and purity may be gained by the following methods: First.—Determine the gravity. Any serious fall below the normal standard shows dilution with water. Second.—Examine by the “ pioskop.” This little instrument consists of a round disk of hard rubber, two and a half inches in diameter, slightly raised toward the middle, with a shallow dish- like depression in the centre, in which a few drops of milk are placed. This is then covered by a glass disk of two and a half inches diameter, transparent in the middle, the rim covered by six ra- dial strips of oil-paint, varying from white to dark gray, and marked with the quality corresponding to it, from “ cream ” to “ very poor milk.” The color of the thin layer of milk, as seen through the trans- parent part of the glass plate, corresponds with one of the six color strips, and its quality is determined at a glance. Third.—Take a tube half an inch in diameter and ten inches high, graduated to one-hundredths, with the 0° a short distance from the mouth. Fill it to the zero with the milk to be examined, and let it stand vertically for twenty-four hours ; then read off the percentage of cream in divisions of the scale. Normal cow’s milk thus treated should give ten to fourteen per cent, of cream. Fourth.—Dilute 10 c.c. of Fehling’s solution (59) with 30 c.c, of water, and heat to boiling in a flask or capsule. Dilute the milk with exactly three times its volume of water, agitate thoroughly, place in a burette, and add gradually to the Fehling solution. The power of lactose to reduce copper is not as great as that of glucose, since it requires 67 milligrammes of the former to do the woi’k of 50 of the latter. On this basis the percentage of lactose may be calculated. ANIMAL FLUIDS. 41 IMPURE MILK. 124. Any great reduction in the proportion of lactose, without serious change in the gravity, tends to show that the milk has been diluted, and the gravity made up by the addition of some foreign material. The milk secreted during the first few days contains colostrum ; it is yel- lowish in color, with gravity from 1,040 to 1,060 ; it contains less lactose than milk, and its casein is replaced by albumen; therefore it coagulates when boiled. The presence of colostrum and of pus in milk may be easily detected by the microscope ; also that of starch, flour, and chalk. Blood 125. Is a red fluid, haying a specific gravity which varies from 1,045 to 1,075. It has a salty, unpleasant taste and a peculiar odor, which, by the ad- dition of H2S04, is said to resemble that of the animal from which it is de- rived. The reaction of blood is alkaline. In the living creature, blood consists of a fluid called plasma, in which corpuscles are floating. The corpuscles are of two kinds, white and red. The latter are derived from the former. They vary greatly in size and shape according to the kind of creature from which they are obtained, and those who are experts in such matters can generally tell by a microscopic exami- nation from what source the blood has been procured. According to C. Schmidt, human blood contains 518 parts of naturally moist corpuscles to 487 of plasma. The plasma consists of water, holding in solution albumen, a small trace of fibrin, salts, fats, and extractive. SPONTANEOUS CHANGES IN BLOOD. 126. Shortly after it is drawn the fibrin undergoes spontaneous coagula- tion, and the corpifßcles being caught in its meshes a clot or coagulum forms. This floats in a tawny fluid called serum, which differs from plasma only in that it does not contain fibrin.- The total amount of fibrin in blood is about 0.2 per cent. The chief constituent of serum being albumen, the most interesting prop- erties of that fluid depend mainly on its presence. SPECTROSCOPIC EXAMINATION OF BLOOD, 127. The coloring matter of the blood is called hemoglobin. When puri- fied and brought in contact with oxygen gas it forms a loose union therewith, and produces oxyhemoglobin. When a solution of oxyhemoglobin, or of diluted blood, is placed between a source of light and the slit of a spectroscope, two dark bands appear in the spectrum between the lines D and E. Of these the narrower and darker is near to D, while the broader fainter band is near to E. The space between them is somewhat wider than the broad band. If a little ammonium sulphide is added to a portion of the fluid under ex- amination, the oxyhemoglobin is reduced to hemoglobin, the two bands dis- appear, and in their place a single broad band takes the place of the bright space of the oxyhemoglobin spectrum. ANIMAL FLUIDS. By the decomposition of hemoglobin hematin is produced. It may he prepared by shaking deflhrinated blood with ether, to which a little glacial acetic acid has been added. When the ethereal solution separates, decant and filter into a test-tube, and examine with the spectroscope. It gives a wide absorption band in the position of the line C. In an alkaline solution the band at C disappears, and two bands, which merge into each other, ap- pear between D and E. TESTS. 128. Coagulation test.—Where pure albumen in solution has been coagulated by heat or by strong nitric acid, or by both agents combined, the precipitate- is white, but if red blood cor- puscles are present in the fluid, the coagulum assumes a choco- late color of varying shade, according to the proportion of disks present. Hence we have a test by which we may detect the pres- ence of blood in serum, or in urine. It is as follows : Add to the suspected fluid sufficient acetic acid to give it an acid reaction ; raise the temperature to the boiling-point. If blood is present, a dark coagulum is formed, and the liquid be- comes clear, assuming its normal color. Hemin test.—Place a drop of blood or a little hematin on a microscope slide, add a very small quantity of common salt and a drop of acetic acid. Warm gently, and examine from time to time under the microscope with a power of two or three hun- dred. As the fluid evaporates, the small, flat, rhomboidal, acute- angled crystals of hemin appear. EXAMINATION OE BLOOD-STAINS. 129. First.-—By the microscope. This requires a thorough knowledge of the appearances of the corpuscles under different conditions. Second.—By the spectroscope. This is applicable when the cor- puscles are disintegrated. The dry blood-stain on cloth, wood, etc., is digested with a small quantity of water containing a little ammonia ; the solution is filtered into a test-tube half an inch in diameter, and placed before the slit of the spectroscope, using- sunlight and a very narrow slit. If the dark bands of oxyhemo- globin appear, no doubt can exist of the presence of blood. If bands do not appear, acidify the ammoniacal solution with a little glacial acetic acid ; agitate the mixture with its own volume of ether ; aid the separation of the ethereal solution by the addi- tion of a little more acetic acid if it is necessary ; place the ethe- real solution before the slit of the spectroscope, when the dark, narrow band of hematin in acid solution will appear in the red at C. Third.—Hemin test may be applied directly to the stain as fol- ANIMAL FLUIDS. 43 lows : Transfer a portion to a microscope slide, rub it with a minute grain of NaCl, cover with thin glass, pass a drop of gla- cial acetic acid under the cover. After some ten minutes, warm very gently, and examine from time to time under the microscope. Conduct the process slowly, and if necessary add a second and a third drop of acetic acid and proceed as before (128). Bile 130. Is the secretion of the liver. It has an alkaline reaction, a bitter taste, specific gravity from 1,036 to 1,033, color varies from green through a red or brown almost to black, it is viscid and froths when shaken. The constituents of bile of greatest interest from a clinical point of view are its coloring matters and its salts. Bile pigment.—ln the bile of the carnivora and of man the golden red color is caused by bilirubin, UioHi tN2O3. In the herbivora, the green tint is due to biliverdin, Ci6HiBN2O4. The latter of these may be derived from the former by exposing an alkaline solution of bilirubin in a shallow vessel to the air, when it absorbs another atom of oxygen. Bile salts are chiefly sodium glycocholate and taurocholate. In the bile of the herbivora glycocholate is in excess; in that of man and carnivora, tauro- cholate. TESTS. 131. First.—For pigments. Gmelin’s test. For this nitroso- nitric acid is required, which is nitric acid containing the lower ox- ides of nitrogen in solution. It may be prepared by exposing strong HN03 to sunlight till it turns yellow, or by diluting with HN03 the green liquid formed in the porous cell of a Grove battery. Place about half an inch in depth of the acid in a test-tube, and holding the tube inclined at an angle of about 45°, pour a diluted solution of bilirubin on the surface of the acid to a depth of a couple of inches; the solution should float on the acid, not mix with it. At the point of contact green, blue, violet, red, and yellow tints appear in the order mentioned. Repeat the ex- periment, using a solution of biliverdin, a similar series of colors is produced beginning with the blue. Another way of applying the test is to place a few drops of either of the solutions on a porcelain plate, and let a drop of nitroso-nitric acid fall in the centre, the colors appear in the form of concentric rings. 132. Second.—Bile salts. Pettenkofer’s test. Pour the puri- fied fluid containing the bile acids into a test-tube, add H3S04 slowly in sufficient quantity to redissolve the precipitate ; the mixture will be warm. Add a small piece of sugar or a little syrup ; a series of colors is jH'oduced, passing from pink through red to purple. The purple color is the characteristic reaction, ANIMAL FLUIDS. The presence of a small quantity of albumen gives a reddish- violet reaction with this test which might lead to error, therefore, the necessity for purification. 133. Gholesterin, C^^HtiO, is another important constituent of bile; is also found in nerve-tissue, serum, excrements, pus, and dropsical effusions. It is tasteless, odorless, greasy, melts at 145° C., and out of contact with air sublimes at 360°. It is soluble in ether and in hot alcohol, from which it crystallizes in thin plates on cooling. It also dissolves in benzole and chloroform. Rubbed or triturated in a mortar with sufficient H2S04 to moisten it, and then agitated with chloroform, a blood-red solution is formed, which, in contact with air, becomes violet, blue, or green. Urine 134, Is the secretion of the kidneys, by which sundry results of retro- grade metamorphosis in the system are conveyed out of the body in solution in water. It represents not only the results of the natural chemical changes, but also of those which are exceptional or abnormal. It is, therefore, best studied: Ist, in its normal, and 2d, in its abnormal state. Physical Characters NORMAL URINE. 135. Color. Is bright amber yellow. It varies from a pale yellow to a reddish-brown, according to the proportion of water and urinary pigments. Condition. It is transparent, free from turbidity, and possesses the prop- erty of fluorescence. Quantity. Varies from 40 to 60 fluid ounces, or from 1,000 to 1,500 cubic centimetres per diem. Is greatly increased in beer-drinkers, in hysteria, and in diabetes. Specific gravity. Varies from 1,015 to 1,080 (110). Chemical Characters. 136. Odor. Is aromatic. Certain articles of food, as asparagus and cauli- flower, give special odors, and also certain drugs, as cubebs and turpentine. 137. Reaction. Differs according as the urine is recently passed or not. If not more than one hour old it is nearly always acid (14), from the presence of acid phosphates of the alkalies. In rare cases it is alkaline immediately after a meal, or when alka- line or earthy carbonate have been taken. Salts of organic acids, i.e. (citrates, tartrates), with the alkalies, also give an alkaline re- action to urine, since they are converted into alkaline carbonates in their passage through the system. If the urine has stood for a time, which varies with the tem- perature, it becomes alkaline by the decomposition of urea, which is its chief constituent. Under these circumstances am- ANIMAL FLUIDS. 45 monium carbonate is produced, winch imparts the reaction in question. It may be recognized by the ammoniacal odor. If the alkaline reaction is produced by volatile alkali or ammonia, the litmus paper regains its red tint when dried. If by the fixed alkalies, the change in color to blue is permanent. If it is possible, urine should always be examined before decom- position begins. If urine has alkaline reaction from the presence of ammonium carbonate at the time it is passed, it is a serious pathological sign, indicative of inflammation of some portion of the mucous membrane of the urinary system. 138. The table gives the average quantity of each ingredient excreted during twenty-four hours, and also the percentage. From it we find that urea and chlorides are the chief solid constituents. It is, therefore, evident, that variations in specific gravity of normal urine are chiefly owing to varia- tion in these constituents. Composition op Urine, Constituents. Grammes. Per cent. Total solids 60.0 to 70.0 4.8 to 4.6 Urea 80.0 to 40.0 2.5 to 8.2 Uric acid 0.4 to 0.8 0.03 to 0.05 Creatinine 0.5 to 1.0 0.036 to 0.062 Hippuric acid 0.8 to 1.0 0.02 to 0.06 Chlorides 10.0 to 18.0 0.7 to 0.8 Earthy phosphates 0.9 to 1.8 0.07 to 0.08 Phosphates 2.5 to 3.5 0.19 to 0.22 Sulphates 1.5 to 2.5 0.16 to 0.17 ABNORMAL URINE. 139. Urine may vary from its normal state in two ways : Ist, by change in the proportion of one or more of the constituents ; and 2d, by appearance of new or abnormal ingredients. VARIATION IN NORMAL INGREDIENTS. 140. It is understood that all determinations in relation to variations in the normal ingredients are to he made on the urine of the whole day of twenty-four hours. Examination of a single specimen is of little or no value. The urine must be passed into a vessel of sufficient capacity to hold the whole quantity passed, say from 7 A.M. of one day to 7 a.m of the next. This should he measured and a sample examined, when valuable indications may be obtained regarding the rate and manner in which chemical changes are taking place in the system. ANIMAL FLUIDS. 141. Is the chief constituent of the urine. It is also found in the blood, and when its removal by the kidneys is interfered with, it appears in all the fluids of the body. It is crystalline, very soluble in water, and deliquescent. It was one of the first of the organic bodies which was made artificially. Increase in the diurnal quantity appears: Ist, with increase in the amount of animal food ; 2d, in acute febrile actions; 3d, in the different forms of diabetes. Diminution arises: Ist, during fasting ; 2d, during.the use of a vegetable diet; 3d, in certain chronic diseases or (cachexies); 4th, in parenchymatous nephritis, especially on the approach of death. No special characteristics of color, condition, quantity, odor, or reaction attend variations in the proportion of urea in urine. UREA OR CARBAMIDE, CON2H4, 142. Examination for excess : Ist, the specific gravity is over 1,030 ; 2d, place f 3 j- of the urine in a test-tube, add one-third its bulk of strong colorless HNOa, and keep the tube at 32° F. or 0° C., by setting it in a mixture of ice and water. If the high gravity is owing to an excess of urea, scale-like cxystals of the nitrate will be formed. If there is effervescence on adding the HN03, it is generally owing to the escape of CO„ from ammonium carbonate produced by the decomposition of the urea. The presence of the lower oxides of nitrogen in the HN03 will also cause an evolution of gas. TESTS. 143. Examination for diminution: Ist, the specific gravity is below the average normal ; 2d, the amount of diminution may be ascertained by finding how much cencentration is required before the specimen yields urea-nitrate crystals when examined as described above. 144, Absolute quantitative determination.—The modern methods are based on the fact that nitroso-nitric acid, hypochlorite or hypobromite of sodium decompose urea into water, nitrogen, and carbonic acid. The quan- tity is measured either by measuring the volume of gas disengaged, or by weighing the carbonic acid, as barium carbonate. Liebig’s volumetric process consists in the precipitation of the urea by per- nitrate of mercury. It is not reliable, since the precipitate varies in the pro- portions of its ingredients. 145. Occurs in the urine of all carnivorous creatures. It requires 15,000 parts of cold water to dissolve it. Only a small part is present in the free state in urine, the greater portion being urates. Like urea, it represents retrograde metamorphosis of nitrogenized tissue, and is supposed to be an intermediate step in the series of changes of which urea is the final result. URIC ACID, Cr.HiN.O3, ANIMAL FLUIDS. It may be prepared from urine, by adding one part of HCI to about thirty of urine, and letting it stand in a cool place for twenty-four hours ; the uric acid then crystallizes, and the sedi- ment may be separated by decantation, and washed on a filter (5). Thus jirepared uric acid is red; it is the so-called brick-dust sediment of urine. In its pure condition it is white. 146. Increase in diurnal quantity appears: Ist, in over-feeding; 2d, lack of sufficient exercise ; 3d, acute febrile actions ; 4th, disease of heart or lungs attended by dyspnoea; sth, where tumors or accumulations in the ab- dominal cavity interfere with the action of the diaphragm ; Cth, in leucae- mia ; 7th, in the uric acid cachexy. Excess of uric acid is generally attended by increased depth in the tint of the urine, and a strongly acid reaction ; sometimes a turbidity and formation of red sediment or crystals in a few hours. The quantity is sometimes scanty ; gravity and odor do not present any special characteristics. Decrease occurs in chronic disease of the kidneys, diabetes mellitus, liydruria, and arthritis. TESTS. 147. Heat.—Examined on platinum foil in the Bunsen flame, uric acid gives off the odor of burning hair, and leaves a residue of carbon, which may be completely burned away ; thus it is shown to be a nitrogenized organic body. 148. Murexid test.—Place a little uric acid in a watch-glass, add two to five drops of strong HNOs, warm over a flame ; the uric acid dissolves. Evaporate very cautiously to dryness, a red residue remains. With NH,HO, this gives a purple red ; with KHO a violet blue, which is evanescent. Increase or diminution may be estimated by treating a normal specimen, and that to be examined, in equal quantities in test- tubes with HCI, and after twenty-four hours noting the amount of uric acid sediment formed. 149, Next to urea the chlorides are found in largest quantity in normal urine. They consist of common salt, NaCl, with a little calcium chloride. It is the presence of NaCl which gives to urine its salty taste. A drop of normal urine evaporated to dryness on a microscope slide, leaves crystals of NaCl easily recognized, when placed in the field of that instrument. Though the chlorides in the urine are taken in that form in the ingesta, and are not produced in the system, they nevertheless show considerable changes in amount under certain conditions of disease. CHLORIDES. 150. Increase is found; Ist, with the free use of salt provisions; 2d, energetic physical or mental exertion ; Bd, during paroxysms of intermit- tent fever, or just before or after ; 4th, in diabetes insipidus ; sth, in dropsy when diuresis intervenes. 151. Deci 'ease : Ist, during repose ; 2d, in acute febrile and inflammatory ANIMAL FLUIDS. 48 actions, the chlorides then appear in such exudates as pleuritic effusions, diarrhoea, etc. ; Bd, in chronic diseases attended by dyspepsia, and in dropsy. As a rule, the chlorides diminish as the disease intensities, and increase as it relaxes. Their absence indicates a very desperate state. In pneumonia they may disappear entirely. The color, condition, quantity, gravity, odor, and reaction of the urine do not present any special characteristics with change in proportion of chlorides. 152. In article 70, Fifth, the reaction between nitrate of silver and a compound of chlorine is described. In the urine, phos- phates are present as well as chlorides (138). Phosphates also produce a. precipitate with argentic nitrate, providing the solu- tion is not acid. To avoid any error in testing for chlorides, the urine should be first acidified with M 0.,, and then agitated. All the precipitate that then forms on the addition of AgN03 so- lution is due to the presence of chlorides, and is curdy in its character. By testing the specimen to be examined against a normal specimen in a companion-tube, any variation in the proper quan- tity is quickly detected. The determination may be made still more satisfactory by testing the specimen against a solution of NaCl in water of the same proportion as that given in the table, article 138, i.e., .8 per cent. Accurate volumetric determination of the chlorides by the use of a stand- ard solution of silver nitrate may be made by adding a few drops of potas- sium chromate to the urine. The red silver chromate begins to be thrown down as soon as all the chloride is precipitated, and before any phosphate forms. The amount of silver solution employed up to the formation of the red precipitate is the measure of the quantity of chloride present. TESTS. PHOSPHATES. 153. The forms under which these are found in the urine are as acid phosphates of sodium, magnesium, and calcium. The sodium salt is solu- ble, but the others are held in solution by the acid reaction of the urine ; they are precipitated when it becomes alkaline. The proportion of phosphates in urine is greater during the day. 154, Increase in phosphates is found: Ist, after the ingestion of phos- phorus, phosphoric acid, and soluble phosphates ; 2d, after an animal diet, especially of brain; Bd, in acute febrile diseases ; 4th, in diseases of the bones and rheumatism; sth, after the use of mineral waters rich in car- bonates ; 6th, after any exhausting'nervous action, as over-stndy and ex- cessive venereal indulgence, also paroxysms of grief and of joy. 155. Decrease is found: Ist, in low gravity urine ; 2d, in diseases of the kidney and heart; Bd, in dyspepsia. The color, condition, quantity, gravity, odor, and reaction of urine con- taining excess of phosphates do not present any fixed.characters when freshly passed. In a short time it often assumes a turbid state, owing to the pre- cipitation of the earthy phosphates. ANIMAL FLUIDS. 49 156. When urine containing excess of phosphates is heated, a precipitation takes place, since these are more insoluble in hot than in cold water. This precipitate closely resembles that pro- duced by albumen under the same conditions. It differs in that it readily dissolves on the addition of a few drops of HNOa, while the albumen precipitated is insoluble, and may even increase in quantity when HN03 is added. TESTS. 157. A satisfactory approximate estimate of the total amount of phosphates in urine may be obtained by the following method : In a test-tube place a column of urine four inches in depth, add a few drops of KHO, enough to give a strong alkaline reaction ; raise the temperature to the boiling-point, and set the tube aside for fifteen minutes, to allow the precipitate to settle. Thus treated, urine containing the normal proportion of phosphates will give a precipitate about half an inch in depth. Any great departure from this indicates the extent of the increase or dimi- nution in proportion of this ingredient. SULPHATES 158. Occur as sodium and potassium sulphates. They are derived either directly from the ingesta or from disintegration of the proteid compounds of the system. They therefore become an indication of the rate at which metamorphosis is taking place in the organism, and especially in the mus- cular tissue. 159. InGi 'ease in proportion of sulphates appears: Ist, after the ingestion of sulphur, sulphuric acid, and soluble sulphates; 2d, from increased con- sumption of flesh or albuminous food ; 3d, in acute inflammation attended by increase in amount of urea, as meningitis, encephalitis, and muscular or articular rheumatism. Decrease appears with the diminished use of albuminous food, at the out- set of typhus fever, and generally in urines of low gravity. The general physical and chemical properties do not show any special characteristics. TESTS. 160. The reactions of H,S04 and Bad., have been explained in article 70 {Fourth). It happens that phosphates also give a precipitate with BaCl2 solution. To prevent this, a little pure Hd must be added to the urine before it is tested with the Bad., solution. Normal urine gives an opaque, milky appearance when tested in this manner. The eye should be trained to the intensity of the whiteness by the examination of a number of normal speci- mens. Any departure from the ordinary test will then give a proximate indication of an increase or a diminution in the sul- phates. ANIMAL FLUIDS. 50 Abnormal Constituents. ALBUMEN 161. Is not a normal constituent of the urine. It sometimes appears temporarily. When it is present continuously, it generally indicates serious pathological change. It appears: Ist, from the inordinate use of egg-albumen ; 2d, when the blood-pressure in the kidney vessels is greater than the normal, as in ob- structed venous circulation; Bd, in changed conditions of the diffusion membranes of the kidney, e.#., Bright’s disease; 4th, when pus, blood, or other albuminous fluid is present in the urine ; sth, in changed condition of the blood-albumen. Generally the color of albuminous urine is lighter than the normal; the specific gravity is usually low—1,004 to 1,025—but Roberts gives a case in which it was 1,065. The other general, chemical, and physical characters present no special points of interest. TESTS. The different forms of albumen and their reactions have been discussed in Articles 115, 116, 117. For the detection of albumen in the urine, the heat-test and that by HN03 are generally employed. 162. Heat-test.—Add sufficient acetic acid to give an acid re- action, then boil. A flocculent precipitate'indicates the presence of albumen. Unless acetic acid is added, a precipitate of phosphates may form ; too much acetic acid may prevent the precipitation of al- bumen. On the other hand, in alkaline urine, heat alone may fail to precipitate albumen, unless the urine is rendered slightly acid, as directed. 163. JSfitric add test is described as follows, in the translation of Hof- mann and XJltzmann’s Avork by Brune and Curtis : “For tlie HN03 test, 10 c.c. of urine should be taken in a wine- glass, and then pure, colorless, concentrated HN03 (not fuming) should be allowed to flow down the side of the glass, forming a layer beneath the urine. Now, if albumen is present, a white zone will appear between the two fluids. This can only be con- founded Avith the urates, which are precipitated in a somewhat similar manner when present in great amount; also with the resin of copaiva. In the case of the urates they are not precipi- tated in the zone betAveen the fluids, but somewhat higher up, and are not sharply defined as a zone, but curl upward from the centre, haA’ing the appearance of ascending smoke. “ 164. If albumen and much urates are present in a urine at the same time, we obtain by the nitric acid reaction tAvo layers, one above the other. The lower layer, sharply defined above and ANIMAL FLUIDS. 51 below, between the colorless acid and the urine, is the albumen. The upper layer, gradually becoming more intense and not sharply defined above, but ascending as a white cloud, consists of the urates. A layer of clear urine separates these two. The layer produced by the resin of copaiva disappears on the addition of a few drops of alcohol. “165. If we apply the nitric acid test to normal urine, we ob- serve between the acid and the urine a brown ring of urine color- ing matters, which in a few minutes becomes more voluminous. In febrile processes, when the urine contains much coloring mat- ter, this ring is very intensely colored. As albumen when present appears in the same zone, this does not form now as a white layer, but is more or less tinged with brown. If much indican is present, the urine often appears a beautiful rose-red or even violet ; from the presence of blood-coloring matters, brown-red ; from undecomposed bile-coloring matters, a beautiful green. If a urine is strongly concentrated and we add HN03, a copious crystalline precipitate of nitrate of urea falls, which, under the microscope, shows the characteristic colored rhombic tables. From a urine rich in uric acid we often see beautiful, shining, light yellow-colored whetstone crystals, which can be easily dis- tinguished microchemically from nitrate of urea, because they are not soluble in water. “ 166. If the urine contains much carbonic acid, either because it is alkaline and contains much ammonium carbonate, or because it has a neutral or even acid reaction, and contains much sodium carbonate or free carbonic acid (as is the case from use of alka- line and carbonated mineral waters), we observe that the fluid, by addition of HN03, becomes sparkling and sometimes even effer- vescent.” BLOOD 167. May appear in the urine hy hemorrhage from the large vessels, by capillary hemorrhage, or from a breaking down of the blood-corpuscles. The color of such urine presents various shades of brownish-red. TESTS. 168. First.—As albumen is present in all cases of hemorrhage, it is precipitated by heat (128). The dark precipitate, and clear- ing up of the urine, which assumes the normal color, causes the presence of blood to be suspected. To complete the demonstra- tion, collect the coagulum on a filter, dry, extract with alcohol containing a little H„SO4, evaporate the solution to dryness and apply the hemin test. Second.—Blood-coloring matter may also be precipitated by adding a little KHO to the urine and raising the temperature ANIMAL FLUIDS. 52 short of boiling ; the phosphates are then precipitated, and, carry- ing down the coloring matter with them, appear of a blood-red color. If the coloring matter is small in amount, the precipitate is dichroic in appearance. Collect the precipitate upon a filter, dry, and apply the hemin test as follows : Warm a little of the precipitate upon a microscope slide until it is quite dry; rub a few fine grains of NaCl into the residue, lay a hair on the mass, cover with thin glass, and conduct the opera- tion as in 129, Third. BILE. 169. In certain conditions of the liver the constituents of bile make their appearance in the urine. In this case the color of the urine changes to dif- ferent shades of yellow to brown. It makes yellow stains on the clothing ; it also acquires a hitter taste. The other general properties are variable. TESTS 170. Are particularly confined to tlie detection of the coloring matters of bile, that is, to Gmelin’s test, as described in article 131, substituting the specimen of urine for the dilute solution of bilirubin. The test may also be made by floating the urine over a layer of ordinary HNO;i in a test-tube, and then introducing H„SO4 while the tube is held in an inclined position, the heavy H2S04 sinks beneath the HN03, and the colors make their appearance as when nitroso-nitric acid is used, e.g., green, blue, violet, red, yellow, from below upward ; the green being the chief and the blue sometimes wanting. The use of Pettenkofer's test requires a troublesome process of purification to make its application reliable. It may, however, be applied directly to the urine as an adjunct to Gmelin’s test. SUGAE. 171. By some, sugar is regarded as a normal constituent of the urine. Ad- mitting that such may be the case, the quantity is exceedingly small. The form in which sugar is present is that of glucose or diabetic sugar, consti- tuting the disease called diabetes mellitus; the quantity may exceed 100 grammes to the litre. Diabetic urine is generally of a light color, and has a high gravity, though sometimes it is very low. The quantity is more than double the ordinary average ;it has reached twenty litres. It is sweet to the taste, and if evapo- rated on a piece of cloth, leaves a sticky stain like honey. It has a whey- like odor. TESTS. 172. Should the urine contain albumen, the albumen must be separated by acetic acid and heat before applying the tests. First.—Trommers test. Add to some of the urine, in a test- ANIMAL FLUIDS. 53 tube, a few drops of solution of sulphate of copper, then add solution of caustic potash in excess ; boil the mixture. If it con- tains sugar, the yellow or red suboxide of copper precipitates. If it does not contain sugar, the precipitate is blue or black. Care must he taken not to use an excess of the copper solution. See articles 57 and 58 for sources of error and cautions. Second.—Moore’s test. Add an excess of KHO to the urine and boil ; a lemon-yellow, yellowish-brown, or a blackish-brown color appears. Treated with a little HN03, the color is destroyed and an odor of molasses produced. Third.—Fermentation test. Add to the urine a little fresh yeast or a few grains of yeast-cake, and set aside for twenty-four hours at a temperature of 70° to 80° F. The sugar undergoes fermen- tation, alcohol and carbonic acid being produced. The white scum which appears dining the fermentation shows the torula cells when examined under the microscope. Fourth.—Quantitative differential density test.—Take two vessels, place in them enough of the urine to fill the urinometer reservoir. To one of the vessels add a little yeast-cake, determine the specific gravity of both, and set aside for twenty-four hours to ferment. Again take the specific gravity. Every degree of specific gravity lost in the yeast mixture is equal to one grain of sugar per fluid ounce of urine. Any variation of specific gravity, owing to change of temperature or other cause, will be shown by the companion vessel, and should be allowed for. Fifth.—Fehling’s quantitative test may be applied according to article 59. Trommer’s and Fehling’s tests are liable to error, since uric and hippuric acid, and the urates, if in large quantity, cause a re- duction of the copper oxide. The most reliable tests in doubtful cases are those by fermentation and polarization. Examination of Liquid Urine. Name. Color. Reaction. Sp. Gr. Heat. HNOs. Other tests. Ammon. Carb. Varies Aik Urea, excess of Varies High.. Crystals of 1 urea nitrate, j Crystals with oxalic acid. Phosphates... Albumen Bile “ “ Varies. White ppt Ppt. dissolves,. White ppt Colored ppt mentation tests. Ppt. with heat. Sol- uble in HN03. Mercuric chloride, tannic acid, etc. i( u Microscopic exami- nation. Iron test. Separation of fat by ether. White SECTION IV. SEDIMENTS AND CALCULI 173. Consist of unorganized or organized substances, which are elimi- nated from the blood, or deposited from the fluids of the body. They are gouty concretions, salivary concretions and tartar, gall-stones, and urinary sediments and calculi. 174. Are nearly white, soft, and friable, are often called chalk-stones. They appear in the joints of persons suffering from gout. Their composition varies greatly, but is made up chiefly of an acid urate of soda, with chloride of sodium and dry epithelium, sometimes they contain urate and phosphate of lime and chloride of potassium. The presence of the uric acid may be shown by the heat and murexid tests (147, 148). GOUTY CONCRETIONS 175. The solid constituents of the saliva are deposited occasionally as small concretions in the ducts of the salivary glands, and commonly upon the surface of the teeth, forming the coating known as tartar. The deposit con- sists in both instances of carbonate and phosphate of calcium, with some al- buminoid body. Submitted to the action of dilute HCI, the mineral matter dis- solves with effervescence, owing to the escape of carbonic acid. The residue is the albuminoid or organic substance. SALIVARY CONCRETIONS AND TARTAR. BILIARY CALCULI 176. Are found in the gall-duct, gall-bladder, and in the intestines. They are sometimes nearly an inch in diameter, and nearly spherical in form. The color is a light brown ; they are greasy, quite soft, and easily cut or crushed. They are formed almost entirely of cholesterin, with a little bile pigment and inorganic matter. The structure in section is radiating. They sometimes exhibit concentric layers. The cholesterin may he extracted and examined according to 133. The residue may be examined with dilute HCI, as in ar- ticle 175. SEDIMENTS AND CALCULI, 55 URINARY SEDIMENTS. 177. When freshly passed, normal urine is clear, but after standing for a short time, a cloud appears in the lower part of the liuid ; this is mucus from the urinary passages. It is best seen by holding the vessel against a dark surface. If the vessel has been carefully cleansed, the urine may re- main therein for a long time, weeks even, without further change ; com- monly, however, it undergoes the so-called 178. Acid fermentation.—This is produced by the action of the phosphate of sodium upon the sodium urate of the liquid. From this, at low temperature, an acid salt of uric acid results, which is quite insoluble and forms a yellowish-red sediment, the reaction of the urine becoming very acid. At higher tempera- tures the whole of the sodium is abstracted from the urate, and a crystalline deposit of uric acid is produced which is brick-red ; sometimes it adheres to the sides of the vessels, and sometimes it floats on the surface of the fluid. Crystals of oxalate of lime are often seen mingled with this sediment. 179. The alkaline fermentation follows upon the preceding, the urine becomes of a lighter color, the uric acid disappears, the reaction becomes neutral, then alkaline, an ammoniacal odor is given off, clearness gives place to turbidity, and a whitish sed- iment forms, which contains ammonium urate, amorphous cal- cium phosphate, and triple phosphate or phosphate of magnesium and ammonium. Under the microscope the turbidity is seen not to consist of suspended phosphates, but of innumerable bacteria, some quiet, some in perpetual movement. This change is the result of the action of a peculiar ferment upon the urea. If the vessel in which the urine is placed is unclean, and espe- cially if soiled with fermented urine, the decomposition is rapid, the acid fermentation does not occur, but the alkaline sets in at once. 180. In abnormal urines, the substances are diffused throughout the fluid when it is first passed, making it more or less turbid ; after a time they sub- side and form sediments. All urinary sediments may be grouped as unor- ganized and organized ; the first may be either amorphous or crystalline. They have been classified as follows by Hofmann and Ultzmann : SEDIMENTS CLASSIFIED. A. Not Organized. a. Amorphous. From alkaline urine. 1. Calcium phosphate. 2. Calcium carbonate. From add urine. 1. Urates of sodium and potassium. 2. Fat. SEDIMENTS AND CALCULI. 56 From acid urine. 1. Uric acid. 2. Calcium oxalate. 3. Cystine. 4. Tyrosine. b. Crystalline. From alkaline urine. 1. Ammonium urate. 2. Triple phosphates. 8. Calcium phosphate. 4. Magnesium phosphate. B. Organized. 1. Mucus and pus-corpuscles. 2. Blood-corpuscles. 3. Epithelium from the various tracts of the urinary apparatus. 4. Cylinders (or casts) and fibrin coagula. 5. Spermatozoa. 6. Parasites and entozoa. 7. Extraneous ohiects. In this series the constituents are arranged according to their form and the frequency of their occurrence, excepting the last. Sediments may be examined in three ways : Ist, by suspend- ing them in the urine by agitation ; 2d, by transferring them by a pipette in the concentrated state to watch-glasses or test-tubes ; 3d, by collecting them upon filters. It is always well to make a preliminary examination of all sed- iments and calculi, by the heat-test described in article 12 ; we thus learn, at the outset, whether the substance is organic or in- organic, and if it is a mixture of both, in what proportions they are present. The sediment should be dried. EXAMINATION OF SEDIMENTS. The following systematic course is partly from Bowman’s ‘ ‘ Medical Chem- istry ” and partly from Hofmann and Ultzmann: Unorganized Sediments. 181. Urates.—Transfer a little of the deposit to a test-tube by means of a pipette, add some of the urine, shake the tube to dif- fuse the sediment through the liquid. First.—Warm the mixture ; if the sediment dissolves, it is prob- ably URATE OF SODA OR AMMONIA. These form the most frequent and unimportant of urinary sediments. Slight concentration of the urine from increased perspiration, and slight fe- brile actions will cause a sediment when the urine cools. The color varies from white to pink and red. The milky urine of infants is of this nature. Second.—Place another portion of the sediment in a tube, add a drop or so of hydrochloric or of acetic acid. Crystals of uric acid will form. Third.— Collect some of the deposit upon a filter, dry it, and examine by heat and the murexid tests (147 and 148) for uric acid. SEDIMENTS AND CALCULI. 57 As is shown in the table of sediments, if the urine is acid, potassium and sodium salts are present They may be differ- entiated by the flame tests and spectroscope (104, 105). If the urine is alkaline, urate of ammonia is present. 182. Phosphates.-—If the deposit does not dissolve when warmed, add to a few drops of the sedimentary urine, in a test- tube, a little acetic acid. Ie the deposit dissolves in acetic acid, it probably consists of earthy phosphates, the nature of which, whether consisting of phosphate of lime or triple phosphate, or a mixture of both, may be distinguished by submitting a little of the deposit to micro- scopic examination. The phosphatic precipitate may be made to reappear on adding either volatile or fixed alkali. 183. Oxalates.—lf the deposit proves insoluble in acetic acid, test another portion with a little dilute hydrochloric acid. If it dissolves in the acid, and the acid solution thus obtained gives, when neutralized with ammonia, a white precipitate, it is prob- ably oxalate of lime. Oxalate of lime dissolves without effer- vescence. If there is escape of C02, and no precipitate on add- ing NH4HO in dilute solution, the sediment is calcium carbonate. 184. Uric acid.—Ip hydrochloric acid fails to dissolve the deposit, it may be tested for uric acid by means of nitric acid and ammonia (147 and 148). Uric acid may also be readily dis- tinguished under the microscope. 185. Mixed deposits.—lf the deposit does not consist of earthy phos- phates, uric acid, urate of ammonia, nor oxalate of lime, it must he exam- ined for the other matters which are occasionally, though less frequently, met with in morbid urine. It must he remembered that, in the majority of cases, urinary deposits do not consist exclusively of any one substance, but contain two or more mixed together, as when the earthy phosphates occur associated with an excess of mucus. The action of the several tests may in this way be more or less masked, and, when taken alone, may lead to erro- neous conclusions. In such cases the microscope will be found of infinite value, and should always, when available, be employed. 186. Where such an intermingling of unorganized deposits exist, they may be found by filtering off the solution formed by each solvent. After the urates have been dissolved by heating, the undissolved portion of sediment may be collected on a filter. When the fluid has drained away, the contents of the filter may be washed into a test-tube and examined by acetic acid for phos- phates. The dissolved phosphates having been filtered off, the remaining sediment may again be separated and examined for oxalates by HCI. In its turn, the sediment from this operation may be examined for uric acid. In the majority of cases decan- tation is preferable to filtration. SEDIMENTS AND CALCULI. 58 Organized Sediments. Chemical tests are not, as a rule, available for detecting the nature of these deposits. The list is given to advance the student’s knowledge of the subject. 187. Pus.—If the deposit sinks readily to the bottom of the vessel, form- ing a pale greenish-yellow sediment, which, on agitation, is again dif- fused readily and uniformly throughout the liquid, it probably consists of pus. Confirm by examination with the microscope for the characteristic corpuscles. 188. Mucus.—lf, on the other hand, the deposit is tenacious and ropy, not mixing uniformly with the liquid when shaken, it probably rep- resents an excess of mucus. 189. Blood.—If the deposit is dark-colored, brown, or red, and has been found not to consist of urate of ammonia colored with purpurine, it probably contains blood ; in which case the clear portion of the urine will give indications of albumen when heated, or when tested with nitric acid. Confirm by 168. 190. Cystine.—When the deposit is white or nearly so, having proved insoluble when warmed, and also when treated with dilute hydro- chloric and acetic acids, and is found to be readily soluble in a solution OF ammonia, the ammoniacal solution yielding on evaporation hexagonal CRYSTALLINE PLATES, it is probably CYSTINE. 191. Fat.—If, when a little of the urine is agitated with half its bulk of ether in a test-tube, and the ethereal solution, after separating from the watery portion on which it floats, is found to leave, after evaporation at a gentle heat, a residue of fat or oily matter, the presence of fat may be in- ferred. The detection of fat is to be regarded with caution, since it may have come from lubricants used in the introduction of a catheter or other instrument. In the case of the following comparatively rare disease, it is, when taken with the color, quite characteristic : 192. Chyle. —lf the urine is opaque and almost milky in appearance, yielding traces of fat when treated with ether, and is found, when exam- ined under the microscope, to contain an abundant white amorphous or granular deposit of albumen or fibrin, together with small, round, colorless corpuscles, it probably contains chylous matter. 193. Epithelium and casts.—The former from all parts of the urinary tract, and the latter from the tubuli uriniferi, are only to be found by micro- scopic examination. In the urine of women, epithelium from the genera- tive organs is generally present. 194. Spei •matozoa.—Are only discoverable by the microscope. They ap- pear with a strong power as small, rounded forms, with a longer or shorter hair-like tail. One seldom has an opportunity of seeing them in motion in the urine. A urine which contains spermatozoa often shows white, cloudy flakes, which, under the microscope, are resolved into a mass of sperma- tozoa, imbedded in a finely granulated substance. Since spermatozoa are very light, they require several hours to settle. After six to twelve hours we find, besides the flocculent lumps, isolated seminal granules. On ac- count of the resisting capability of these structures, they may be found in the urine after several days. Spermatozoa are found; First.—After coition, nocturnal pollution, etc., when a part of the semen remains behind in the urethra and is washed out later by the urine. Second. —With spermatorrhoea. We also observe involuntary emissions in typhus. SEDIMENTS AND CALCULI. 59 In the urine of women we find spermatozoa after coition—a fact which may have great medico-legal importance. 195. Parasites.—First, bacteria, regarded by some as plants, by others as animals. The urine is always cloudy, even after the sediment settles. The account of the following forms is taken from the work of Hofmann and Ultzmann : a. The monad forms. These are round, punctiform bacteria, which either remain quiet or show a quivering motion. One must exercise care not to confound with these the earthy phosphates which have a molecular move- ment. While the movement of a lifeless structure goes on in one place, the monad forms of bacteria change their position in the field of the microscope. b. The rod forms. These are very small rods, scarcely the diameter of a blood-corpuscle, and immeasurable in thickness. Both ends are generally swollen and knob-formed. They are sometimes at rest, and sometimes moving through the field. c. The vibriones. These are made up of the above-mentioned forms—- two or more rod-like bacteria, one hanging on to another, moving sometimes spirally and sometimes with a motion resembling that of a fish’s tail, going hither and thither with great rapidity. d. The hair forms, or chain forms. These are long, often reaching across the entire field, and are to be distinguished only by their length from the vibriones. Only with a very high magnifying power can their jointed com- position be recognized. They move but seldom, and then very sluggishly, in the manner of a serpent. c. The zoogloa forms. These appear as masses of punctiform bacteria held together in a common gelatinous mass, resembling a precipitate of earthy phosphates held in mucus. All these forms may be observed in the same urine and often under the same cover-glass. Second.—The yeast plants (Saccharomyces urince).—These are single vesi- cular cells, of the size of blood-corpuscles, and of somewhat oval shape. Usually, however, they are made up of small cells arranged like a rosary, some of the beads having two or three bud-like cells attached. This fungus appears in much less quantity than the bacteria, and is found mostly in acid urine on a warm day. This plant has the greatest similarity to the yeast plant of beer (Saccharomyces cerevisicp), without being identical. In diabetic urine this form occurs, but more vigorously developed. Third. —Sarcinw.—This form has the greatest similarity to Sarcina ventri- culi, but is appreciably smaller. They are arranged in groups of two, four, eight, etc., and the small cells are built up in cube form and present the ap- pearance of a cross-bound bale of goods. The urine in which sarcinse are found is chiefly alkaline, and in the sedi- ment we find also calcium and triple phosphate. The evacuation of sarcinse lasts for weeks, sometimes for months. Fourth.—O'idium lactis.—This appears in the form of long cells, recog- nized by their granules being arranged at regular intervals. These occur not infrequently in the fermenting urine of diabetes. Fifth.—Penicillium glaucum.—Besides the before-mentioned fungi spores of this plant may exist in the urine. In great part these appear as germs. Sometimes they are covered with a coating of fine urates, appearing furry and brown-red, or the development is further advanced, and the branching forms become extended and make up a network of interlacing fibres. The spores for the evolution of all the forms of fungi mentioned develop outside of the bladder. This rule, however, has exceptions. The sarcinse are always excreted with the urine from the bladder. Sometimes this may SEDIMENTS AND CALCULI. 60 be the case with bacteria, though this may be explained from the use of uncleaned sounds or catheters. Cases have come to our knowledge, though very rarely, where there was certainty of no instrument having been intro- duced previously into the bladder or urethra. It is very difficult to ascer- tain whether these forms of fungi have any influence on the reaction or fermentation of the urine. The small chain fungus appears not alone in alkaline urine, but in every case in which an albuminous substance becomes fetid or decomposed. We therefore find the same in the secretions of dif- ferent ulcers, in ichor, and in cholera stools. In this place we may mention, in passing, an indication which was for- merly considered a characteristic sign of pregnancy. The name kyesteive was formerly given to the membrane which forms on the surface of long- standing urine of pregnant women, and which consists of an interlacing net- work in which calcium and triple phosphates, bacteria, and sometimes also animal organisms are imbedded. It forms, however, upon the urine of men, and has of late lost its significance. 196. Exti ’aneous objects, consisting of atmospheric dust, fibres from all kinds of textures, starch granules, etc., will be found delineated in Roberts’ work on “Urinary Diseases.” URINARY CALCULI 197, Are composed of one or more of the normal or abnormal materials which have been described as composing urinary sediments. They vary in size from that of sand nearly to that of the fist. They usually consist of a nucleus of a crystal of uric acid, a minute blood-clot, a tube-cast, rarely of some foreign substance which has been introduced into the urethra. Around this phosphates, carbonates, and other substances are deposited in concentric layers. Uric acid is the usual constituent of vesical calculi; they are small and hard, unless mingled with phosphates, which is frequently the case. Calcium oxalate calculi are very rough on the exterior, hence they have been called mulberry calculi. The triple phosphate and calcium phosphate calculi are soft and readily crushed. To examine a calculus.—Cut it through the middle by means of a fine saw. Its structure is thus exposed, and if the line of section has been well chosen, the nucleus is seen and its origin explained. The composition of each layer may then be determined by following the plan given for the examination of urinary sediments. As a preliminary the dry-heat test may be applied in each case. ALPHABETICAL LIST OF SYMBOLS AND FORMULA. Ag, silver. Cu, copper. AgsAsOs, silver arsenite. AgCl, argentic chloride. AgCj, argentic cyanide. » ( argentic nitrate. AgN03, - » ( nitrate or silver. Cu2C2H3O2, cupric acetate. CuCO3, cupric carbonate. ( cupric arsenite. ( uHAsOg, \ Paris green. Cu2HO, cupric hydrate. CuO, cupric oxide. As, arsenic. Asl3, arsenious iodide. As203, arsenious oxide. As2o6, arsenic oxide. As2S2, realgar. Cu2o, cuprous oxide. CuS, copper sulphide. Cu504,5H20, cupric sulphate. FesOls, ferric chloride. As2S3, orpiment. Fe26HO, ferric hydrate. H, hydrogen. BaCl2, barium chloride. C, carbon. H3As03, arsenious acid. H3AsO4, arsenic acid. HC2H3O2, acetic acid. H0C3H403, lactic acid. C5H4N403, uric acid. C6Hioo6, starch. C6Hi2Ob,H2O, glucose, grape sugar. C]2H24012, lactose, milk sugar. CI6HiBN2O3, bilii’ubin. HCN or HCy, hydrocyanic acid. H2CO3, carbonic acid. Ci6HiSN2O4, biliverdin. C 26 cholesterin. CO, carbon monoxide. H2C204,2H20, oxalic acid. HCI, hydrochloric acid. HNOs, nitric acid. carbon dioxide. I carbonic acid gas. CON2H4, urea or carbamide. CaCl2, calcium chloride. CaCO3, calcium carbonate. Ca2HO, calcium hydrate. CaS04, calcium sulphate. Cl, chlorine. H2O, water. H2S, hydrogen sulphide H2SO4, sulphuric acid. Hg, mercury. HgCl, mercurous chloride, calomel. HgCl.., mercuric chloride, corrosive Hgl, mercurous iodide. sublimate. SYMBOLS AND FORMULAE. 62 Hgl2, mercuric iodide. HgO, mercuric oxide. Hg20, mercurous oxide. HgS, mercuric sulphide. Hg2S, mercurous sulphide. K, potassium. K2C03, potassium carbonate. K2Cr04, potassium chromate. KCy, potassium cyanide. KHO, potassium hydrate, caustic potash. KI, potassium iodide. K(SbO)C4H4O6,H2O, tartar emetic. N, nitrogen. NH3, ammonia gas. NH4CI, ammonium chloride. NH4HO, ammonium hydrate. NIIjHS, ammonium sulphide. NH2HgCI, white precipitate. | Na, sodium. i Na2C03, sodium carbonate, i Nad, sodium chloride. NaHO, sodium hydrate. O, oxygen. P, phosphorus. PH3, phosphide of hydrogen. Pb, lead. PhCO3, white lead or carbonate. i Pb3C2H302, lead acetate, sugar of lead. Pbd2, lead chloride. PbCr04, lead chromate. Pbl2, lead iodide. PbO, litharge. Pb3o4, minium, red lead. PbS, lead sulphide, galena. PbSO4, lead sulphate. Sb2o3, antimony oxide. Sb2S3, antimony sulphide. potash. ARRANGEMENT OP LABORATORY. The apparatus, reagents, and chemicals required for the conduction of this course are as follows. The list also gives the location of each article, thus enabling the students and assistants to find it without unnecessary loss of time. First.—The laboratory is provided with tables on which there are no per- manent fixtures except Bunsen burners. Everything is stowed away in cases. There is, therefore, every opportunity to keep the tables clean. Each table accommodates two students seated opposite to each other. The students’ places or seats are numbered in regular order. Second.—Each student is provided with a rack containing apparatus and reagents in continued use, and bearing the number of his seat. The loca- tion of the articles in question is indicated in the list by the word rack. Third.—For each table and for the pair of students occupying it, a box is provided which contains ninety-six small bottles in which the specimens and reagents mentioned in the list are placed. These are designated by numbers attached to the bottles, which correspond with those given in the list. Fourth.—For each table a low box is provided in which burettes and other glass instruments are preserved. In the list these are referred to as case. Fifth.—Cases are provided in which the rack and boxes, together with other pieces of apparatus, are stored by the students at the close of each day’s work. The shelves of the cases bear numbers corresponding to the numbers of the seats occupied by the students. Sixth.—A special case contains specimens which are rare or costly, and the instruments required for purposes of illustration. This is designated in the list as museum. Seventh.—The general supplies of chemicals and glass-ware, and the special reagents which are used in quantity, are stored in stock cases; these are in- dicated by the term stock. ARRANGEMENT OF LABORATORY. 64 Name. Location. Acid acetic, glacial, ......... rack. “ hippuric, museum. “ hydrochloric, pure, ........ rack. “ hydrocyanic, ......... No. 1. “ lactic, . . . . . . . . . “ 2. “ nitric, pure, . . ... . . . . rack. “ nitroso-nitric, . . . . . . . “ “ oxalic, No. 3. “ sulphuric, commercial, ....... rack. “ “ standard sol., ....... stock. “ “ aromatic, ........ No. 4. “ uric, 5. Albumen, dry, .......... “ 6. “ solution, ......... stock. Alcohol, commercial, Amalgam, No. 58. Ammonium, chloride, . . . “ 7. “ carbonate, . . . . • . . . . stock. “ hydrate, dilute, rack. “ sulphide, . . “ “ urate, ......... museum. Antimony, ........... No. 8. “ alloy (Britannia metal), . . . . . “ 9. “ “ (type metal), “ 10. “ oxide and sulphide (Kermes), . . . “ 11. “ and potassium tartrate, . . . . . “ 12. “ sulphide, native powdered, . . . “13. “ “ precipitated, . . . . . “ 14. “ wine of, . . . . . . . “ 15. Aqua calcis, .......... stock. “ destillata, “ Argentic, nitrate, ......... No. 16. Arsenic, . . . . . . . . . . “ 17. “ bisulphide, 18. “ oxide, 19. “ tersulphide, . . . . . . . . “ 20. Arsenious iodide, . . . . . . . “ 21. “ oxide, “22. “ “ two grains in tube, ...... museum. “ porcelainous, ........ “ “ vitreous, ......... “ Arsenite, copper, ......... No. 23. “ potassium solution (Fowler), . . . . . “24. Balance, ........... museum. Battery, Grove or Bunsen, . . . . . . . “ Battley’s solution, No. 25. Barium, chloride, . . . . . . . . , “ 26. Bile-stains on linen, . . , . . . . . . “ 27. Bilirubin, museum. Biliverdin, “ Blood-stains on linen, ........ No. 28. Blow pipe, . case. Blue pill, ........... No. 60. ARRANGEMENT OF LABORATORY. 65 Name. Location. Britannia metal, ......... No. 9. Brunswick-green, museum. Bunsen burner or spirit-lamp, ....... case. Burette, 25 c.0., “ Calcium carbonate, . . . . . . . . . No. 29. “ oxalate, . . . museum. “ oxide slacked, stock. “ phosphate, precipitated, ...... No. 30. “ sulphate, . . . . . . . “ 31. “ “ solution, •....,. stock. Calculi, biliary, . . . . . . . . . . museum. “ gouty, “ salivary, ......... “ “ urinary, . Calomel, ........... No. 67. Capsule, porcelain, 2 ounces, ....... case. Carbon dioxide apparatus, . museum. “ filters, .......... “ Casein, .....'. “ Chalk, No. 29. Charcoal, ........... case. Cholesterin, museum. Chrome-yellow, . . No. 48. Clarke’s soap test, ......... stock. Corks, ........... case. Corrosive sublimate, ......... No. 63. Copper foil slips, 1 in. x-fV thin, ......“ 32. Cream tube, .......... case. Cupric acetate, .......... No. 33. “ arsenite, 23. “ carbonate, . . “ 34. “ oxide, . . . . . . . • “ 35. “ sulphate, crystals, . . . . • “ 36. “ “ saturated solution, ...... rack. “ sulphide pyrites, ........ No. 37. Cuprous oxide, .......... u 38. Cylinder, ........... rack. Cystine, . . . . . . . . . . museum. Dialyzer, “ Dover’s powder, . ......... No.-73. Epsom salt, “56. Ether, sulphuric, stock. Fat or oil in emulsion, . . . . . . “ Fehling’s solution, “ Ferric chloride, No. 39. Fibrin, museum. Files, rat-tail and triangular, 4 in., case. Filters, 3 in. diameter, “ Filtering paper slips, 1 in. x 10 in,, “ Flask, 1 ounce, .......... rack. ARRANGEMENT OF LABORATORY. 66 Name. Location. Fowler’s solution, ......... No. 24. Funnel, rack. Glucose, No. 92. Goulard’s extract, 53. Gratings, museum H2S apparatus, .......... “ H2S water bottle, 1 gallon, ........ stock. Hemoglobin, .......... museum. Hematin, ........... “ Hemin, “ Hydrargyrum, .......... No. 57. Indigo sulphate, . . . . . . . . . . “ 40. Iron, oxide, dialyzed, . . . . . . . “ 41. “ sulphide, for HoS apparatus, ...... stock. “ wire, very fine, 1 in. long, ...... No. 42. Isinglass, . . . . . . . . . . . “ 43. Kermes mineral, . . . . . . . . “ 11. Lactose, . 98. Laudanum, . . . . . . . . . “ 74. Lavender comp, tinct., . . . . . . “ 44. Lead, 45. “ acetate, . . . . . . . . . “ 46. “ carbonate, 47. “ chromate, . . . . . . . . . “ 48. “ iodide, . . . . . . . . . “ 49. “ oxide, 3to 4 red, . . . . . . . “ 50. “ pipe, tin lined, 51. “ protoxide, . . . . . . . . • . “ 52. “ subacetate, Goulard’s, . . .. . . . “ 58. “ white, 47. Litharge, ........... “ 52. Litmus cubes, .......... “ 54. Magnesium, oxide, . . . . . . . . . “ 55. “ sulphate, . . . . . . . “ 56. “ “ saturated sol., ...... stock. Measuring tube, ......... rack. Mercury, No. 57. “ alloy or amalgam, . . . . . . . “ 58. “ with chalk, . . . . . . . “ 59. “ mass (blue pill), “60. “ unguentum, “61. Mercur-ammonium chloride, . . . . . . “ 62. Mercuric chloride, . . . . . . . . “ 63. “ iodide, . . . . . . . . “ 64. “ oxide, 65. “ sulphide, “ 66. Mercurous chloride, . . . . . . . . “ 67. “ iodide, “68. ARRANGEMENT OF LABORATORY. 67 Name. Location. Mercurous oxide, . . . . . . . ■ . No. 69. “ sulphide, “70. Microscope, . . . . . ... . . . museum. Milk, condensed, ......... stock. Millon’s reagent, “ Minium, ........... No. 50. Morphia, sulphate solution, “71. McMunn’s elixir, . . . . . • • • “ 72. Nessler’s reagent, ......... stock. Opium, alkaloid morphia sulph. sol., ..... No. 71. “ elixir, “72. “ pulv., Dover’s, ........“ 73. “ tinct., “74. “ “ camph., . “75. Orpiment, . . . . . . . . • . “ 20. Oxyhemoglobin, ......... museum. Paris-green, .......... No. 28. Paregoric, 75. Phosphorus, .......... 11 76. “ red, “77. Pipette, simple, rack. “ 10 c.c., case. Pioskop, “ Platinum foil spoon, ......... rack. Polariscope, .......... museum. Potassium, bichromate, . . . . . . . No. 78. “ chlorate, . . . . . . . . “ 79. “ cyanide, . . . . . . . . “ 80. “ ferrocyanide, . . ... “ 81. “ hydrate, sp. gr. 1,050, ...... rack. “ iodide, ......... No. 82. “ permanganate, . “ 83. “ “ test solution, ..... stock. ‘ ‘ and sodium tartrate, . . . ... . “ Pouring rod, .......... rack. Prisms, museum. Realgar, No. 18. Retort, case. Saccharose, . . . . ... .... No. 91. Schweinfurth’s-green, . . . . . . , . “ 84. Silver, nitrate, 16. Slop jar, . case. Sodium, carbonate, . . . . . . . . . No. 85. “ “ standard sol., ...... stock. “ chloride, ......... No. 86. “ “ standard sol., . . . . . stock. “ glycocholate, ........ museum. “ hydrate, ......... stock. “ hypochlorite, . . . . . . . . “ 68 ARRANGEMENT OF LABORATORY. Name. Location. Sodium, phosphate, ’ . . . No. 87. “ “ standard sol., . . . . . stock. “ sulphate, “ ...... “ “ taurocholate, ........ museum. “ urate, .......... “ Sorrel, salt of, No. 88. Spectroscope, museum. Spirit lamp or Bunsen burner, . . . . . . . case. Starch, ........... No. 89. Strychnia, sulphate sol., . . . . . . . . “ 90. Sugar, cane, “91. “ grape, “92. “ milk, 93. Tartar on teeth, . . . . . . . . . museum, “ emetic, .......... No. 12. Tubes, test, small and large, . . . . . . . rack. “ sublimation, ......... case. “ thermometer, for jets, . . . . . . . “ Turmeric paper, .......... stock. Type metal, .......... No. 10. Tyrosine, museum. Urea, No. 94. Urinary sediments, ........ . museum. Urinometer and cylinder, . . . . . . . rack. Vermilion, .......... No. 66. Washing-bottle, .......... rack. Watch-glasses, “ Water bath, . . . . • • ■ • • • case. “ distilled, stock. “ hard, . . . . • • • • • “ “ sewage, “ White precipitate, ......... No. 62. Wine glass, . . ■ . . • . • • ■ rack. Wood slips, .......... case. Yeast-cake, .......... No. 95. Zinc slips, i wide and 1 in. long, thin, “96. INDEX. Acid, arsenic, 7 arsenious, 7 hydrocyanic, 3, 25 lactic, 40 mineral, 22 nitric, test in urine, 50 nitroso-nitric, 43 oxalic, 23 prussic, 25 reaction, 5 uric, 46 Acids, 22 Albumen, 38 in milk, 41 in urine, 50 Albumenoids, 88 Albuminates, 38 Alcohol, 3 Alkalies, 26 Alkalimetry, 26 Alkali reaction, 5 Alkaloids, 28 Amalgam, 13 Ammonia, 26 in water, 33 Ammonio-nitrate-silver test, 9 sulphate-copper test, 9 Ammonium' carbonate, 45 compounds, 26 Animal fluids, 36 Antidotes, 11, 12, 14, 16, 19, 22, 23, 24, 25, 27, 29, 30 Antimony, 11 sulphide, 12 Arsenic, 7 oxide, 7 sulphide, 9 Arsenious anhydride, 7 iodide, 7 oxide, 7 Arsenites, 7 Atom, 3 Atomicity, 8 Atomic weight, 3 Bacteria, 59 Barium chloride, 22 Base, 4 Battley’s solution, 28 Bile in urine, 43, 52 Bilirubin, 43 Biliverdin, 43 Blood, 41, 51 in urine, 58 Blue pill, 13 Bread, copper in, 19 Brunswick-green, 17 Calcium, test for, 35 Calculi, 54 urinary, 59 Carbamide, 46 i Casein, 38 | Casts in urine, 58 Chlorides, 47 Chloroform antidote, 30 Cholesterin, 44 Chrome-yellow, 15 Chyle, 58 Clark’s soap test, 34 Colostrum, 41 Compound bodies, 3 Concretions, 54 Condenser, 3 Copper compounds, 16 Corpuscles, 41 Cosmetics, 7 Cream tube, 40 Cupric oxide, 16 Cuprous oxide, 16 Curd, milk, 40 Cystine, 58 INDEX 70 Decantation, 2 Decoction, 2 Deoxidation, 18 Desiccation, 2 Diabetic urine, 52 Dialysed iron, 11 Dialysis, 7 Distillation, 8 Donovan’s solution, 7 Dover’s powder, 28 Element, 8 * Epithelium, 58 Epsom salt, 24 Equation, 3 Evaporation, 2 Fat, 58 Fehling’s solution, 18, 40 test, 53 Fermentation in urine, 55 test, 58 Ferric hydrate, 11 Fibrin, 89 Filtration, 2 Formula chemical, 3 Fowler’s solution, 7 Frog test, 29 Funnel, 2 Galvanic test, 14 Gases in water, 31 Gmelin’s test, 43, 52 Goulard’s extract, 15 Hematin, 42 Hemin test, 42, 52 Hemoglobin, 41 H2S test, 8, 11, 18, 15, 17 Hydrargyrum, 18 Hydrogen test, 21 Hydrometer, 36 Ice, 31 Incineration, 3 Infusion, 2 Inorganic bodies, 3, 4 in water, 31, 33 Iron, dialysed, 11 peroxide, 11 Kermes mineral, 11 Kyesteine, 60 Lactometer, 39 Lactose, 40 Laudanum, 28 Lead, 15 Lemonade, H2S04, 16 Liebig’s test for HCy, 25 urea, 46 Lime in water, 33 Litharge, 15 Litmus paper, 5 Magnesia, 22, 23 Manipulation, 1 Marshall Hall’s test, 29 Marsh’s test, 10, 12 Marsh water, 32 McMunn’s elixir, 28 Mercuric iodide, 7 Mercury, 13 Metallic poisons, 20 Milk, 39 condensed, 39 impure, 41 Millon’s reagent, 37 Molecular weight, 3 Molecule, 3 Moore’s test, 53 Mucus, 58 Murexid test, 47 Kessler’s reagent, 33 Nitrites, test for, 33 Nitrogenized bodies, 4 in water, 31 Non-nitrogenized bodies, 4 in water, 31 Nux vomica, 29 O'idium lactis, 59 Opium, 28 Organic bodies, 3, 4 in water, 31 Organized bodies, 4 Orpiment, 7 Oven, hot-air, 2 Oxalates, 57 Oxyhemoglobin, 41 Ozone test, 21 Parasites, 59 Paregoric, 28 Paris-green, 7, 17 Penicillium glaucum, 59 INDEX 71 Permanganate test, 33 Pettenkofer’s test, 43, 53 Pharaoh’s serpents, 25 Phosphates, 48, 57 Phosphorus, 21 Pickles, poisonous, 19 Pioskop, 40 Plasma, 41 Platinum spoon, 3 Poisons, 6 corrosive, 6 inorganic, 7 irritant, 0 neurotic, 6 organic, 38 Potassa, 36 Potassium, cyanide, 9 ferro-cyanide, 8, 19 test for, 34 Preserves, poisonous, 19 Proteids, 37 Pus, 58 Pyrites, copper, 17 Quicksilver, 13 Radical, 3 compound, 3 Rain-water, 31 Ratsbane, 7 Reaction, 5 Realgar, 7 Reduction test, 8 Reinsch’s test, 10, 13, 14 Residue from water, 34 Saccharomyces urinae, 59 Salt, 5 Sarcinse, 59 Saturnine poisoning, 15 Sediment, brick-dust, 47 Sediments, 54 classified, 55 examination of, 56 Serin, 78 Serum, 41 Scheele’s-green, 7 Sohweinfurth’s-green, 7, 17 Silver nitrate, 33 Snow, 31 Soda, 26 Sodium glycocholate, 43 taurooholate, 43 test for, 35 Solution, 1 Sorrel, salt of, 23 Sour-krout, copper in, 19 Specific gravity, 36 Spermatozoa, 58 Springs, 31 Starch, iodide-potassium, test, 21 Strychnia, 29 Sublimation test, 8, 11, 13, 15, 17 Sugar in urine, 53 tests, 18 Sulphates, 49 Symbols, 3 Tartar emetic, 11 on teeth, 54 Temperature, sp. gr. corrections, 37 Tincture, 3 Toxicology, 10,12, 14, 16, 19, 31, 23, 24, 25, 27, 28, 29 Trommer’s test, 53 Urates, 57 Urea, 46 Urine, 44 Urinometer, 36 Vacuum, air-pump, 3 Valence, 3 Vegetables, poisonous, 19 Verdigris, 17 Verditer, 17 Vermin killers, 39 Vitriol blue, 17 Volumetric analysis, 36 Wash, black and yellow, 14 Water, 31 bath, 3, 3 lead in, 16 purification, 35 Wells, 32 Whey, 40 Yeast plants, 59