TWO 
INTRODUCTORY LECTURES 
ON 
materia medic a, 
DELIVERED 
AT THE OPENING OF THE COURSE, AND AT 
THE COMMENCEMENT, 
OF 
THE VEGETABLE MATERIA MEDICA, 
AT 
Mr. GRAINGER’S THEATRE, 
WEBB STREET, MAZE POND, BOROUGH, 
AND AT 
THE NEW MEDICAL SCHOOL, 
LITTLE DEAN STREET, SOHO. 
By FRANCIS BOOTT, M.D. 
LONDON: 
PRINTED FOR S. 1IIGHLEY, 174 FLEET STREET, 
AND WEBB STREET, MAZE POND, BOROUGH. 
1827. PRINTED BY RICHARD TAYLOR, 
SHOE-LANE, LONDON. TO 
THE GENTLEMEN ATTENDING THE CLASSES OF 
MATERIA MEDICA, 
THESE LECTURES, 
PUBLISHED AT THE REQUEST OF SEVERAL OF THEM, 
ARE AFFECTIONATELY DEDICATED, 
BY THE 
AUTHOR. INTRODUCTORY LECTURE 
ON 
MATERIA M E D I C A. 
Gentlemen, 
Among the sciences comprehended in the study 
of Medicine, there is one of great importance, from 
the frequency of its application, known under the 
general name of Pharmacology, the explanation of 
which is the object of this course of Lectures. 
It is that department of medicine which includes 
all that is necessary to be known of the means we 
employ in the prevention, the alleviation, and the 
cure of disease. 
It more particularly embraces the natural hi- 
story of medicines, or what is commonly called the 
Materia Medica ; their preparations, or Pharmacy, 
their uses and effects, or Therapeutics. 
In teaching what is generally included by the 
term Medicine, it is indispensable that the different 2 
INTRODUCTORY LECTURE 
divisions of the general science should be consi- 
dered separately, though it is impossible to make 
a strictly artificial division of that which in practice 
is indivisible. The Anatomist must encroach upon 
the Physiologist; and the latter cannot explain the 
functions, without describing generally at least the 
parts which are more particularly the province of 
the anatomist. The Pathologist must also allude 
to those parts of the body affected in disease, and 
to their functions ; and he must be precise in his 
directions upon Therapeutics and the Materia Me- 
dica. The lecturer on the last must refer at every 
step to the nature of those diseases in which his 
remedies are to be applied, and he also encroaches 
on the Chemist; who in his turn must enumerate 
amid the objects subjected to his analysis, those 
which belong to the Materia Medica. 
There is in fact an inseparable connection between 
the different branches of medicine; but the separate 
consideration of each is indispensable, from the 
multiplicity of objects they embrace: and this detail 
is attended with the most important advantages 
to the pupil, who is led to observe the same thing 
at different times under different points of view. 
At one time it is brought before him grouped with 
many others, which are analogous to it in their 
nature; and at another it is examined separately, and 
its peculiar characteristics pointed out. There are 
frequent allusions made by different Lecturers to the 
same thing ; yet each has some shade of difference: 3 
ON MATERIA MEDICA. 
so that no mind ardent in the pursuit of knowledge 
can retire from explanations so varied, without find- 
ing its own researches, on which it must alone rely 
for sound knowledge, materially aided by the varied 
instructions it has received. 
Between some of the sciences included in the 
study of medicine there is at particular points a 
close bond of union ; but they insensibly deviate, 
each pursuing its appropriate path.—The materials 
of the Materia Medica, like those of the other phy- 
sical sciences, belong to the Chemist; but the uses 
and effects of medicines belong to the Physician,—I 
mean to him who devotes his time and talents to 
the practice of our art, under whatever denomination 
he may be known to the world. 
Nor is this department of the profession without 
its interest and its importance in the scale of 
sciences. It teaches the nature and the application 
of those remedies which the chemist has partly ex- 
plained, but which he cannot make use of in the 
prevention or cure of disease. He exhibits the 
ingredients which compose them, but he does not 
show how extensively applicable they are to the 
relief of human suffering. They stand arranged 
in his laboratory, as specimens of the productions 
of nature or of art, and he discourses upon some of 
their properties; but he does not make known their 
diviner nature, which chance or experiment has 
revealed to the physician in the rude or in the 
cultivated state of society. 4 
INTRODUCTORY LECTURE 
To him, however, we owe much of the precision 
of our knowledge respecting them; for he has taught 
us to correct the errors we had committed in com- 
bining one with another, and by his admirable 
analysis has presented us with hitherto unknown 
substances, in which the active properties of the 
medicine reside, by the aid of which we are enabled 
to study their effects with greater precision, and to 
simplify our prescriptions. 
It is impossible to trace the history of the 
Materia Medica from the earlier ages of the world. 
Medicine must have been coeval with man ; for 
the instincts of our nature suggest resources in 
the emergencies of pain and sickness. We are in- 
stinctively prompted to change a painful position, 
to apply the hand upon a part where pain is felt, 
and under the restlessness of suffering to seek 
silence and repose. In many of the common im- 
pressions of disease, the relief of heat, of cold, of 
pressure and of friction, would rapidly be suggested 
to the mind. The use of different articles of food 
and the knowledge of their effects would suggest 
their application on particular occasions. The 
chilliness so common at the commencement of 
acute diseases would lead the savage to bask in the 
rays of the meridian sun, and to wrap himself in 
the skins of winter. 
It has been remarked, that that which first satis- 
fied a want, and thus relieved a pain, may be con- 
sidered as the first medicine, and the instinctive ON MATERIA MEDICA. 
movement which prompted the relief as the first 
physician. As experience and observation in- 
creased, the wants of the body in its various neces- 
sities would be understood; and these would be pro- 
vided against by the possession of such things as 
were found to be most beneficial to it. The inter- 
course of individuals, of families, and of tribes, 
would enlarge the variety of these means and the 
diversity of their application. Travels to remote 
countries would exhibit different manners and dif- 
ferent remedial agents;—commerce would afford the 
facility of their dispersion ; and thus the blessings 
arising from these provisions of nature would be 
extended. 
At first, diseases could only be treated by such 
means as were suggested to the individual or those 
around him. Appeals would naturally be made to 
the sympathies and to the intelligence of others, in 
whose superiority the most reliance was placed; and 
where there was no established authority to refer 
to, the common feelings of humanity would be de- 
veloped and called into action. 
That such was the process in the infancy of me- 
dicine we learn from history. Herodotus informs 
us, that in his time the Babylonians and Chaldeans 
had no physicians. When an individual among 
them was taken ill, he was removed to a public 
place, and those who passed by were compelled by 
law to cpiestion the sufferer upon his condition. All 
those who had seen a case like it, or been similarlv 6 
INTRODUCTORY LECTURE 
affected, suggested such means of relief as their 
memory or their experience could supply. 
The historians of our art, (and of all of them 
I would recommend Sprengel to your attention,) 
inform us that these visitations of calamity were 
in the earlier ages generally ascribed to the anger 
of the gods, and propitiations were made to move 
their pity or avert their displeasure. It is natural 
therefore to find that those, who first made the 
practice of medicine the object of their attention, 
were dignified with the attributes of divinity, and 
raised to the rank of gods at their decease. Altars 
were dedicated to them; and thus medicine fell to 
the peculiar province of priests, who became physi- 
cians, by unfolding the oracles consulted by the 
people.—This will explain many of the absurdities 
that appear in the practice of the earlier ages; for a 
blind superstitious faith in forms and ceremonies 
would preclude all appeals to observation and reason. 
But this refuge of medicine in the temples of relig ion 
was not without its advantages; for the people, by 
blending the relief they received with the idea of the 
direct interference of their divinities, were prompted 
to record the benefits conferred upon them by votive 
tablets t and thus, much useful knowledge was 
handed down to posterity. The walls of the temples 
in Egypt were covered with inscriptions, consisting 
of the recommendation of remedies, and descrip- 
tions of the diseases in which they were applicable. 
The Greeks imitated the examples of the Egyptians ON MATERIA MEDICA. 
7 
in this respect, and Hippocrates is supposed to 
have derived much of the information contained in 
his Aphorisms from the facts thus recorded. In- 
deed Strabo informs us that from the registers in 
the temple of Esculapius at Cos, he tormed his 
Plan for a Proper Diet. 
When philosophy began to be publicly taught 
in the schools of Greece, medicine formed a part 
of it, though the celebrated teachers did not prac- 
tise the art themselves. It was brought to Greece 
by those who travelled in the East: and one of the 
most celebrated men of antiquity, Pythagoras, who 
travelled in Asia Minor and Egypt, brought the re- 
sults of his investigations to the school he formed 
at Crotona. As it became better understood, and 
its importance to the welfare of society more fully 
appretiated, it was cultivated by distinguished men, 
who exclusively devoted their time and talents to 
its pursuit. 
Hippocrates, who died 377 years before the Chris- 
tian sera, brought it by his admirable genius to a 
high state of perfection, and his writings have been 
the admiration of all succeeding ages. 
To give you an idea of the feelings with which 
this great man regarded the profession of physic, 
it is only necessary to quote a passage of his works, 
where he enumerates the qualities he exacted of 
those who came to study medicine. 
“The physician,” he says, “should be known by a 
simple, modest and decent exterior, by a grave de- 8 
INTRODUCTORY LECTURE 
portment, by delicacy in his conduct to females, and 
by affability and mildness toward all men. Patience, 
sobriety, integrity, prudence and skilfulness in his 
art, should be considered as essential qualities. He 
should not seek riches or the superfluities of life, 
and should often heal gratuitously, for the sake of 
the gratitude and the esteem of others. He should 
succour the indigent and the stranger; for if he 
loves man, he will love his art. When called upon 
to speak of any disease by the attendants of the 
sick, he should not use lofty words, or a studied 
and pompous diction, for nothing sooner betrays 
incapacity;—it is imitating the idle buzzing of the 
hornet. In any disease which admits of a choice 
in the mode of treatment, the most simple will 
always be preferred by an enlightened mind, to 
which all imposition is hateful.” 
But it is not my intention to trace the progress 
ot medicine. I have only led you to the considera- 
tion of its early obscurity, to show that any accurate 
history of the Materia Medica cannot be given. 
Nor would it be desirable to call your attention to 
the subject, it we had precise knowledge of the 
means used from the earlier ages in arresting the 
progress of disease. It would be a history of the 
credulity of the human mind, for in no subject has 
that ciedulity been more abused than in medicine. 
It is sufficient for my purpose cursorily to allude 
to the Works of Dioscorides and of Celsus, the 
former of whom has given us the first and onlv ON MATERIA MEDICA. 
9 
complete treatise of antiquity on the Materia Me- 
dica. He was a Greek physician of Anazarba in 
Cilicia, and is supposed to have lived in the reign of 
the Emperor Nero, about the 50tli year of our sera. 
For seventeen centuries his work was regarded as 
the only one on Botany and the Materia Medica, 
and it is said to be still in high repute among the 
Turks. He was commented upon till the revival of 
letters; but from the vagueness of his descriptions, 
taken from uncertain and variable characters of the 
plants to which he alludes, his commentators had 
ample scope for conjecture, and Haller remarks 
that their controversies with each other were only 
terminatedby despair of success. The best edition of 
his Works was published in folio at Lyons in 1598, 
with a Latin version and notes by Saracin. Of his 
commentators Matthiolus is the most celebrated. 
An edition in folio with large wood-cuts was pub- 
lished in Latin at Venice in 1583 and 1604 by 
Valgrisianus. 
Some of our most valuable remedies from the 
vegetable kingdom are mentioned by Dioscorides ; 
as Opium, Squill, Aloes, Castor-oil, Polypody-root, 
Myrrh, Ammoniac and Assafcetida. He describes 
two preparations of the Poppy, the Meconion and 
Opos. The meconion was the juice of the capsules 
and leaves squeezed out in a press. It was weaker 
than the Opos (which is our Opium), as you will per- 
ceive by his directions for obtaining it, exactly like 
those now followed in Turkey and in this country. 10 
INTRODUCTORY LECTURE 
“ Whoever desires,” he says, “to gather the Opos 
or juice must proceed thus. After the heads are 
moistened with dew, let him cut round the asterick 
with a knife, but not penetrate through them; and 
from the sides cut straight lines on the surface, and 
draw off the tear that flows with his finger into a 
shell. And let him come again not long after, for 
it will be found standing upon it, and the day 
following it will be found in the same manner. 
It is proper to rub it in a mortar, and forming it up 
to set it by.” 
The Romans derived their knowledge of medi- 
cine from those Greek physicians who resorted to 
Rome at the time when that capital was rapidly 
advancing to the empire of the world. Among the 
Romans themselves the sciences were in a rude and 
uncultivated state. Cullen remarks, that we have 
evidence of this in the Works of Cato the Censor, 
in which we find an incantation for the reduction 
of a dislocated limb, and that the Brassica was with 
him at least an almost universal remedy. Cato 
died during the third Punic war, 149 years before 
the Christian aera; and about half a century after- 
wards Asclepiades settled in Rome. Celsus tells 
us that his maxim was to cure tute, celeriter, et 
jucunde; and that his remedies were abstinence, 
friction, and gestation.—Themison who succeeded 
him is entitled to our remembrance, from having 
introduced Leeches into practice. 
Celsus is supposed to have written his elegant ON MATERIA MED1CA. 
11 
treatise on Medicine about the commencement of 
our aera. In his 2nd and 5th books there is an 
enumeration of a great variety of medicines, and 
Elections tor their preparation and use. A beautiful 
edition of his Work published at Edinburgh by Dr. 
Milligan, will afford you many facilities in referring 
to the medicines noticed by Celsus ; for it abounds 
with many interesting notes, copious synonyms de- 
ihed from our best modern works, and a scale of 
doses adapted to our measures. It would be idle 
to enumerate all that he recommends ; for many 
of them are either wholly unknown to us, or neg- 
lected at the present day. To give you an idea, 
however, of the antiquity of some of our common 
icmedies, I may mention that he describes prepara- 
tions of Copper, Iron, Lead, Antimony, Sulphur, 
Gum-arabic, Tragacanth, Mastiche, Galba- 
num, Scammony, Elatejrium, Black and White Hel- 
lebore, Aloes, Alum, Cinnamon, Pepper, Hartshorn, 
Saffron, the bitter Almond, Cardamom, Linseed, 
Poppy tears (the Opos of Dioscorides and our 
Opium), and the Cantharides (not our fly, but the 
Meloe Cichorei). In several parts of the 5th book of 
this truly classic writer, we meet with many useless 
and absurd remedies. He gives formulae for 29 
plasters, and one of them is for a fractured skull; as 
if so formidable an injury could be alleviated by an 
adhesive compound of copper scales, frankincense, 
wax, suet and oil. 
Pessaries were used for the medicinal effects of 12 
INTRODUCTORY LECTURE 
the ingredients employed, and not for mechanical 
support. The various substances in use were en- 
veloped in soft wool, and thus introduced into the 
vagina. Celsus enumerates the composition of 
seven; and they were to be administered for evacu- 
ating blood, for softening the womb, for inflamma- 
tion, for expelling a dead foetus, for hysteria; and 
one, compounded of lion’s fat and rose oil, for con- 
ception. 
But it is not necessary to dwell upon these fanci- 
ful and absurd remedies. Similar errors are to be 
found in all works during the infancy of science, 
and should not provoke us to feelings of contempt 
for the works of antiquity. They are the chaff amid 
the wheat, to separate which may require labour, but 
which cannot affect the value of the true grain. All 
knowledge is progressive; and such is the thirst for 
it in the mind of man, that he unconsciously embraces 
falsehood with truth, from the fond hope which he 
cherishes of advancing something that may contri- 
bute to the welfare of his fellow creatures. We 
are in an intermediate state between the compa- 
rative darkness of antiquity, and the light that will 
dawn on future ages. Many things which are now 
received and trusted in as truths, will pass away be- 
fore the enlarged experience of man ; and our suc- 
cessors will undoubtedly rank 11s but as one degree 
above those who preceded us. We all know the 
advances that have been made in chemistry within 
our own time. A new power was discovered in ON MATERIA MEDICA. 
13 
galvanism: it was applied to bodies that were con- 
sidered simple in their nature, and they were de- 
composed by its agency. This light may be but 
the faint traces of the rising sun. We tread the my- 
sterious maze of Nature, ever varying, ever new, 
infinite in variety and in extent. The human mind 
is inadequate to comprehend the whole. Its powers 
are nourished by the wisdom of its time, and obtain 
at best but a feeble growth, scarcely developed in 
the many, and only so far matured in the few gifted 
individuals of the age, as to enable them to look 
a little beyond the horizon of doubt and ignorance, 
which bounded the perceptions of those who pre- 
ceded them in the progress of investigation. As 
knowledge advances, the mind takes from the first 
a wider range. In the infancy of science it was rude 
and uncultivated : as that advances, so do the intel- 
lectual faculties progressively become developed ; 
and instead of undervaluing the labours, however 
imperfect, of our predecessors, we should honour 
them as the pioneers in the march of wisdom, whose 
efforts were directed to clear the thorny wilderness, 
and leave a smooth and open path for us to advance 
rapidly to the limits to which they had attained. 
We are performing the same useful office for our 
successors; and no mind of impartiality among them 
will undervalue our labours, because we had not 
brought to perfection that which can only be gained 
by successive efforts, and by the collected wisdom of 
the different ages of man. 
Between the first age of the world, with its irn- 14 
INTRODUCTORY 1ECTURE 
perfect rudiments of knowledge, and the present 
time, with its proud display of sciences, and its 
widely extended learning, there is tf one simple 
but sublime connexion*,” like that which exists be- 
tween the majestic course of some mighty river, 
flowing through fields pregnant with bloom and 
with fertility, and the shallow rivulets and the in- 
fant streams in the rocky wilderness from whence 
it sprung. If we trace the deep and swelling water 
to its head, we shall undoubtedly find our admira- 
tion successively diminish as we approach its 
shallow source; but, on retracing our steps, we shall 
be compelled to admit that there is no abrupt line 
of separation ; that the channel widens as we pro- 
ceed ; and that the magnificent stream which first 
attracted our wonder and admiration, is the mighty 
mass of waters from a thousand sources, obscure in 
their origin and insignificant in their character. So is 
it with the stream of human knowledge. Its sources 
are equally obscure or undiscovered ; but it has in- 
creased by time, and will increase, as new springs 
of intellect shall arise in succeeding ages to swell its 
already majestic torrent, which flows onward, bear- 
ing on its lucid wave the best blessings to the mind 
and to the heart of man. Nor can this narrow 
world place limits to its course ; and if we embark 
upon its crystal tide, nor loiter on the barren wreck- 
strewn beach of ignorance, we shall be carried by 
its blessed stream to other worlds, to higher intel- 
* See Channing’s Observations on Milton. ON MATERIA MEDICA. 
15 
ligences, and to a happiness that knows neither 
limit nor decay. 
Galen was the last of the Greek physicians of 
any celebrity, and the most distinguished of all 
except Hippocrates. He formed a new system of 
Materia Medica, founded on a theoretical view of the 
qualities of medicines, which he supposed to depend 
on the general properties of heat, cold, dryness, and 
moisture. He died in the 200th year of our sera, 
having during a part of his life at least practised .*t 
Rome, and in little more than two centuries after 
his death that capital was taken by Alaric. 
Science had long before drooped. Superstition 
and despotism had shed their baneful influence on 
learning, and palsied the energies of the mind beyond 
the power of recovery. A long night of darkness 
succeeded, and the faint traces of the returning sun 
of science were first perceived in a remote and un- 
expected quarter of the globe. The scattered rays 
which preceded his rising, and which shed their 
feeble influence in the middle ages upon the rude 
nations of Europe, first dawned on the literary 
establishments of the Arabians in Spain. That 
country was conquered by the Saracens in 712; and 
to their physicians we owe the revival of the 
sciences, which they exclusively cultivated, during 
the rt ign of barbarism over the classic soils of 
Greece and Italy. The names of Rhazes, Avicenna 
and A\ errhoes, form a connecting link between the 
great men of antiquity and the distinguished philo- sophers of modern times. Rhazes died in 923, and 
Averrhoes in 1206. Though they made no im- 
portant changes in the theories of medicine, they 
introduced, far better, a milder practice. We are 
indebted to them for some of the most valuable 
articles of the Materia Medica : for Rhubarb, 
Senna, and Manna; for many important chemical 
remedies ; and for sugar, which superseded the use 
of honey. 
INTRODUCTORY LECTURE 
The Arabian physicians were the sole authorities 
appealed to in Europe during the dark ages. Galen’s 
Works had been translated into Arabic, and he and 
Avicenna ruled despotically for several centuries. 
Their authority was at last disputed in the l6th 
century, by men who hurst the trammels imposed 
upon the human intellect, and who first began to 
appeal to the authority of Nature, by observing her 
works and drawing wisdom from the fountain head. 
Printing had been invented about the middle of the 
preceding century, and Luther by his opposition to 
the Church of Rome had excited a general spirit of 
inquiry. In the year 1453 Constantinople was 
taken by the Turks, and the literary men from that 
capital sought refuge in Italy, bringing with them 
the language and the literature of Greece. The 
writings of Hippocrates and of Galen were now 
read in the original, freed from the errors which 
had been diffused into them by the Arabians ; and 
at last Vesalius of Brussels, born in 1514, was bold 
enough to question the anatomy of Galen. He was ON MATERIA MEDICA. 
led to believe that Galen had obtained his knowledge 
of this science from the dissection of quadrupeds; 
and at the age of twenty-seven he published his 
own system, which eventually prevailed, and de- 
stroyed that implicit faith in the works of antiquity 
which had been previously cherished. The road of 
innovation thus opened was trod by other adventu- 
rous minds; and systems, speculations and discove- 
ries, rapidly followed, till by the labours of a series 
of powerful intellects the Sciences were advanced 
far beyond the limits to which they had attained in 
antiquity. Medicine became moulded to any shape 
best suited to the speculations of the age, and the 
chemical, the mathematical theories, the doctrines 
of the living principle and of irritability rose suc- 
cessively to influence for a while the nature and 
the treatment of diseases, and the supposed action 
of remedies. 
But a vast field of observation had now been 
opened by the discovery of a new world, where 
Science had never trod, and where innumerable ob- 
jects awaited the researches of Philosophy, by the 
aid of which the Physician was to rise triumphant 
over one at least of the most formidable diseases 
that had hitherto baffled human skill, and proved 
widely destructive of human life. The boundaries 
of the world and the limits of human knowledge 
were equally enlarged by the discovery of America. 
An impulse was given to the energies of the mind 
by the genius of Columbus, which diffused itself in 18 
INTRODUCTORY LECTURE 
every direction, and was felt in every investigation. 
It became no longer an object of ambition to seek 
for wisdom in the mazes of antiquated lore; for a 
new world had descended as it were from Heaven, 
enriched with the treasures of Paradise, and bloom- 
ing with hitherto unseen beauty, like that which 
first attracted the admiring gaze of our Parents in 
the garden of Eden. Instead of seeking for reme- 
dies in the unsystematical pages of Dioscorides, the 
medical philosopher essayed the properties of the 
Bark and the Ipecacuanha ; and in these two pre- 
cious drugs alone, found, with the exception of 
Opium, more virtue than in the whole Materia 
Medica of antiquity. 
Columbus returned from his first voyage on the 
15th of March 1493, and in 1509 the Gum Guai- 
acum was introduced into Europe. This was fol- 
lowed by Sarsaparilla in 1530, by Sassafras in 1580, 
by Bark in 1640, and by Ipecacuanha in 1648. 
Bark, which Geoffroy emphatically calls “the gift 
of God,” was not known till 1638. It must he 
considered as one of the most precious additions 
ever made to Medicine; for its powers have been 
found successful in all climates, in arresting one of 
the most common and most formidable diseases to 
which mankind is liable. Many anecdotes are re- 
lated of the discovery of its virtues, in curing Inter- 
mittent Fevers. One of these is, that an individual 
ill of Ague, was suddenly cured by drinking the 
waters of a pool in which trunks of the tree were ON MATERIA MEDICA. 
19 
lying. The first authenticated notice of its use was 
in the case of the Countess Cinchon, wife of the 
viceroy of Lima. This lady returned to Spain in 
1640, and first made the medicine known to Europe. 
It was called the Countess Powder, and her name 
was eventually affixed to the genus, in acknowledge- 
ment of her services to mankind.—No one contri- 
buted so much to the general and judicious use of 
this invaluable remedy in Europe as Sydenham. 
Ipecacuanha was first mentioned as a common 
remedy for the Dysentery in Brazil, by Pison, in his 
Histoire Naturelle de V Ipecacuanha, and by Marc- 
grave in his Historia Rerum Naturalium Brazilice, 
published in 1648. But it was not much known 
till 1672? when LeGras brought it to Paris, on his 
return from South America. It was administered 
at first in large doses, and fell into disrepute until 
the year 1686, when a druggist of the name of Gar- 
nier bought a large quantity of it, and confided the 
secret of its virtues to his physician Afforty, who 
had cured him of a dangerous illness. Afforty had 
received a present of the drug, but attaching little 
importance to it he sent it to Helvetius the father 
of the celebrated philosopher. Helvetius used it 
with great success in Dysentery, and placards were 
carried about Paris, advertising a new and safe re- 
medy for this formidable disease. Louis XIV. who 
was ill with the complaint sent his minister Colbert 
to purchase the secret of Helvetius, who sold it for 
1000 Louis d’or. He cured the king, and was raised 20 
INTRODUCTORY LECTURE 
to the highest honours of his profession. In 16*98 
Sir Hans Sloane published a paper in the Philoso- 
phical Transactions on its virtues, and first recom- 
mended its use in England, nine years after the death 
of Sydenham. Dover gave additional celebrity to 
this medicine in 1760 by combining it with Opium; 
and his powder, the Pulv. Ipec. Comp, of our pre- 
sent Pharmacopoeia is still in general use as a 
Diaphoretic. 
The improvements in the practice of medicine 
since the commencement of the 17th century have 
been so various and important, that though some 
notice of them is required, the limits of this Lecture 
will not admit of much detail. The collateral 
branches of the art were successfully studied, and 
every important addition made to Anatomy, Physi- 
ology and Chemistry, had its influence in practice. 
Bacon had led the way to the study of true philo- 
sophy, and Newton had given the most sublime 
evidences of the results to be obtained from a rigid 
system of observation and induction. In 1619 
Harvey demonstrated the circulation of the blood; 
and Sydenham, who died in 1689, bad brought me- 
dicine under the dominion of careful observation at 
the bed-side of the nature of diseases and the effects 
of remedies. Compared with those who preceded 
him, with his cotemporaries, and with many authors 
of a later age, he appears to us almost as an inspired 
writer, whose sagacity was derived from sources in- 
accessible to other men. The cool regimen in fevers ON MATERIA MEDICA. 
21 
which he so successfully introduced, forms one of 
the most remarkable aeras in Medicine. At the pre- 
sent time we do not pay much attention to his labo- 
rious investigations respecting the diversity of Epi- 
demics, from the simpler views we have been taught 
of the nature of Fevers by Dr. Armstrong, who has 
brought this subject to a precision never attained 
before, and which in the present state of our know- 
ledge leaves so little to be expected from our suc- 
cessors. Sydenham was lost in the maze of the 
various aspect of the different Fevers of different 
years, and supposed their varieties to be infinite. 
Dr. Armstrong has taught us that all Fevers may 
be ranked under three heads,—the Congestive—the 
Simple—and the Inflammatory; and by directing a 
simple mode of treatment for each, has made this 
most important part of practice easy to the com- 
prehension of any one. 
He has given us the only preeise rules for the 
application of our remedies; and by pointing out 
the different stages of fever, the symptoms which 
attend them, the conditions on which these sym- 
ptoms depend, especially the Bronchial affection in 
specific fevers, to which he first showed their putrid 
or malignant symptoms were referable, and which 
before were vaguely ascribed to debility,—and by 
directing a precise mode of treatment, applicable 
to each stage, has shown when and how far the in- 
terference of Art is admissible, and where Nature 
must be left to work her own cure. The boldness 22 
INTRODUCTORY LECTURE 
and promptness of his practice in arresting the pro- 
gress of a dangerous inflammation is only equalled 
in excellence by his cautious forbearance in the 
stage of collapse, and by the free administration of 
opium in large doses, to allay the irritation which 
follows copious bleeding,—he has given a great, 
and, I believe, a hitherto unkn own power to the Phy- 
sician, which has materially contributed to the suc- 
cess of his practice. 
It will be sufficient for me to allude to some of 
the other improvements in Medicine ; and among 
them I may notice the prevention of Scurvy by at- 
tention to the diet, air, clothing, and mind of the 
sailor on long voyages, for which we are indebted to 
Captain Cook : to the ventilation of prisons,—to 
the introduction of inoculation,—and the blessings 
which have been experienced from vaccination. 
Though we have treatises on Poisons in the 
works of antiquity, this subject was not under- 
stood till the present age. The antidotes used by 
the ancients were excessively complicated, and this 
branch of practice was purely empirical, until the 
nature and effects of the different poisons were care- 
fully studied, and their antidotes and treatment as- 
certained by experiment. 
Morbid Anatomy, which has been prosecuted 
with such ardour and success since the days of 
Morgagni, has given us the most precise know- 
ledge ot the effects of various diseases on the struc- 
ture of the body; and by studying the symptoms of ON MATERIA MEDICA. 
23 
disease with reference to these morbid alterations, 
we are enabled to judge more accurately of the 
power of remedies, or of the hope of any good re- 
sulting from their use. It cannot be denied that 
at the present day many diseases are considered 
hopeless, which formerly were regarded as fit ob- 
jects of practice. But this should only encourage 
us in our attempts to prevent that which in pro- 
gress is incurable. By our precise knowledge of the 
condition of the different structures in some dis- 
eases, we at least are taught to do no harm, if we 
can do no good ; and by cautious management with 
regard to diet, rest, temperature, composure of 
mind, we have it in our power to prolong exist- 
ence, and to make the close of life more comfort- 
able and endurable. 
With regard to the introduction or the more 
precise application of particular remedies, I may 
notice the use of the Alkalies in the lithic diathe- 
sis ; the Acids in the Alkaline or earthy deposits in 
urine; of the Digitalis, the diuretic qualities and 
doses of which were first ascertained by Withering 
in 1785, and the application of which as a sedative 
was recommended by Ferriar and Currie. 
Dr. Black showed that the Alkaline Carbonates 
owed their mildness to the union of the Alkali with 
Carbonic Acid, whence Magnesia was obtained in a 
state of purity by the application of heat. 
Goulard introduced the use of his Solution of the 
Acetate of Lead as a lotion. 24 
Arsenic was recommended by Winterbottom in 
Ague in 1795? and Fowler employed it in his solu- 
tion, still in use under the name of Liquor Arse- 
nicalis. 
INTRODUCTORY LECTURE 
The Protoxide of Mercury, the mildest prepara- 
tion of the metal, which is now so extensively em- 
ployed in the Hydr. c. Creta and the Blue Pill, 
came into use at the beginning of the 18th century. 
Calomel was first described by Crollius in 1609. 
Corrosive Sublimate was mentioned by Wiseman 
in his “ Surgery ” about 1734. 
In 1797 Cruikshank used the Nitric Acid suc- 
cessfully in Syphilis, and thus gave the first modern 
proofs in detail of this disease yielding to other 
remedies than Mercury. By adopting the antiphlo- 
gistic treatment, Dr. Thomson of Edinburgh has 
since perfectly cured all forms of this disease. 
Cold Affusions in the ardent forms of fevers were 
recommended by Jackson in 1791, and advocated 
with eloquence by Currie in 1798. 
Hyoscyamus came into use in 1762. 
Belladonna was used by the lamented Saunders 
for dilating the Pupil, to prevent the adhesions of 
the Iris when inflamed, and to facilitate the opera- 
tion on the Lens. 
Colchicuin has recently become a medicine of 
great power in Rheumatism and Gout, and is of 
unquestionable utility in inflammatory affections. 
Burnt Sponge was an old remedy in Bronchocclc. 
1 lie discov cry of Iodine has shown that its virtues ON MATERIA MEDICA. 
were dependent upon that singular substance, which 
is now used externally with success in that disease. 
The rapid and very imperfect sketch of the pro- 
gress of the Materia Medica which I have taken, 
will convince you of the importance of this branch 
of your profession, and of the benefits that have 
resulted to mankind from it. Where the alleviation 
of human suffering is the object of our efforts, we 
cannot employ our time or talents in a nobler pur- 
suit than in seeking for enlarged means to control 
with success the ravages of disease. Though the 
Materia Medica as a science has not the imposing- 
character, or those memorable seras, which mark the 
progress of Anatomy, Physiology, and Chemistry, 
it is as essentially useful to mankind; for without 
precision in the knowledge and use of the materials 
it includes, the most perfect knowledge of the other 
sciences will little avail us in practice. 
The present time furnishes some of the most re- 
markable examples of the good to be derived from 
the study of this branch of medicine. I allude to 
the discovery of the vegetable alkalies. We are at 
present unable to speak confidently of the advan- 
tages of these discoveries, as sufficient time has not 
elapsed for us to put them to the test of extensive 
experience. One preparation of them, however, is in 
general use, and is certainly one of the most elegant 
and valuable gifts which the ingenuity of man ever 
made to medicine. The Sulphate of Quinine pos- 
sesses all the admirable qualities of bark, which in 26 
INTRODUCTORY LECTURE 
itself was often objectionable from the bulk of its 
dose and its nauseous taste: we now, however, can 
administer it in a concentrated form, and in such 
small quantities that no inconvenience is felt from 
its use. 
It is only by attention to the nature of diseases, 
and to the nature and effects of remedies, that we 
can obtain any success in practice. The knowledge 
of the present day is more precise, because greater 
attention has been paid to diseases and to the active 
properties and mode of action of medicines. The 
number of the students of Nature has increased, and 
the labours of each have contributed something to 
the general stock of our knowledge. It is your duty 
to search in the pages of such observers for the 
details of their observations and discoveries : and 
though you may hear of the inutility of reading,—for 
such opinions are promulgated by some men, who 
are themselves authors,—it behoves you to discri- 
minate between the arrogance of false and the hu- 
mility of true wisdom. If the student who has all 
to acquire on his entrance to a profession, the learn- 
ing of which is consecrated in the pages of such 
men as Hippocrates, Celsus, Sydenham, Morgagni, 
Haller, Hunter, Pott, Corvisart, Bayle, Laennec, 
Jenner, Parry, Thomson, Armstrong, Allison, and 
other writers of eminence,—is told it is useless to 
read, where shall he turn for that knowledge which 
is to guide and support him in the painful em- 
barrassments of his professional career ? Is he to ON MATERIA MEDICA. 
27 
derive it from Lectures,—the mere brief abstracts of 
that vast sum of knowledge, which should be deeply 
imbibed, since the subjects it embraces are those 
connected with human existence and human hap- 
piness,—and can any considerations demand more 
study and reflection from a mind anxiously alive to 
the responsibilities reposed in it ? It is your duty 
to make yourselves especially acquainted with the 
modern literatqfe of your profession; for simpler 
views are now taken of diseases, because the veil of 
ignorance has been rent asunder, which formerly 
shrouded them in mystery and doubt. A humbler 
faith is felt in the powers of Art over many of 
them; and the time is fast approaching when the 
pernicious system of empirically administering drugs, 
which can have no other effect than that of wasting 
the failing powers of life and adding to the evils of 
disease, will be abolished from the practice of phy- 
sic. A great and salutary reform in this respect 
has already taken place, and is silently pursuing its 
course ; for the complicated prescriptions of former 
days are now rarely seen or heard of. If they are 
in use, they may be traced to the blind influence of 
habit in minds which have existed in a state of 
sluggish inactivity for years, and not kept pace 
with the improvements in Medicine. It behoves you 
as students to learn the improved Pathology and 
Therapeutics of the present age, and to know so 
much of the past errors of practice that you may 
avoid them in your own career. 28 
INTRODUCTORY LECTURE 
It was formerly deemed sufficient to know the 
names and doses of drugs ; and they were admini- 
stered in one established routine of pill, potion and 
powder, and unremittingly applied, not from any 
process of reasoning as to their mode of action or 
effects, or for any precise object; but because there 
was an associated affinity between the names of dis- 
eases and their established antidotes,—a belief that 
the disorders of the body were to be combated and 
overcome exclusively by the latter, and that success 
would depend on the amount of drugs thus admi- 
nistered. No distinction was drawn between re- 
covery and cure, between the salutary efforts of 
nature and the effects of remedies, between death 
from disease and destruction from poison; and 
thousands were hurried to their graves by the very 
means used to restore health and prolong life. If 
the disease, in itself incurable, and the nature of 
which was unknown, did not yield to one class of 
remedies, another was tried, and another, till death 
freed the victim from the charitable efforts, yet real 
persecution, of his physician. 
Such practice is not permitted at the present day ; 
or if it be, it is only because the light which has 
burst on the minds of the best educated members of 
the profession has not yet enlightened the public 
generally. The best informed men, however, out of 
the profession are now sufficiently aware of the ca- 
pabilities of our art to discriminate between the 
Quack and the enlightened Pathologist, between the ON MATERIA MEDTCA. 
29 
fool and the man of knowledge : and that free ex- 
ercise of judgement, which now reaches every de- 
partment of professional life, and influences the 
success of men in proportion to their acquirements 
and to the just respect of the world, will eventually 
expel ignorance and empiricism from the dominions 
of Physic. 
Your ambition should be to avail yourselves of 
the present facilities for the acquisition of know- 
ledge presented to you in this School and in similar 
establishments ; and if you anticipate future distinc- 
tion, remember that your hopes can only be ground- 
ed on the nature and extent of your professional ac- 
complishments. If they are established on any other 
foundation,—if you suppose that there are other 
means to arrive at knowledge, than patient inves- 
tigation and diligent application,—you deceive your- 
selves ; for you reason against a law of Nature, and 
would destroy the immutable connexion between 
cause and effect. 
The profession you have chosen is the noblest of 
all professions ; for you sacrifice many of the happy 
and peaceful pursuits of life to familiarize yourselves 
with the aspects of disease and the bitter sufferings 
of your fellow-creatures, that you may alleviate or 
cure the one and sympathize with the other. If you 
do this successfully, you will have the noblest of all 
rewards and the sweetest of all recompense; for 
you will be blest with the approbation of your own 
minds, and the gratitude of others, which will de- 30 
INTRODUCTORY LECTURE ON MATERIA MEDICA. 
scend upon you, like the dews of Heaven, to enrich 
you, and to beautify you with the perennial blooms 
of Honour and of Love. 
Remember in your pursuits the exquisite lan- 
guage of Solomon: “Happy is the man that findeth 
wisdom, and the man that getteth understanding: 
for the merchandize of it is better than the mer- 
chandize of silver, and the gain thereof than fine 
gold. Length of days is in her right hand, and in 
her left hand riches and honour. Her ways are 
ways of pleasantness, and all her paths are peace.” INTRODUCTORY LECTURE 
THE VEGETABLE 
MATERIA MEDICA. 
Gentlemen, 
Having in the preceding Lectures described those 
articles of the Materia Medica which are obtained 
from the mineral kingdom, I now pass to those af- 
forded by the vegetable and animal kingdoms.—It 
is from these that we derive our food; but it is 
from the Vegetable Kingdom principally that we 
obtain our most important medicines: for no re- 
medies can compare with Opium, Bark, Ipecacu- 
anha, Rhubarb, Aloes, Colocynth, Colchicum, &c. 
The products of animal life used in Pharmacy and 
Medicine are neither numerous nor important: they 
are generally inert, and employed as the vehicles of 
more active ingredients,—Cantharides alone pos- 
sessing active properties. Castor and Musk are 
rarely employed; while the animal Oils are prin- 32 
INTRODUCTORY LECTURE 
cipally used in plasters and ointments. Our atten- 
tion, therefore, is principally to be confined to Ve- 
getables and their products. Some authors have 
laboured to draw a precise distinction between Me- 
dicines and Aliments. 
They define a Medicine to be a substance which, 
taken into the stomach, is not decomposed and 
made into chyle,—that it modifies the condition of 
that organ, and does not become an integrant part of 
the body ;—while Aliments are rapidly transformed 
into chyle, and go to supply the waste of the body 
by being united to different parts of it. 
There is nothing so diffieult as rigorous definition. 
—If we go back to the earliest ages of the world, 
before definitions were thought of, we shall find 
that little else than Aliments were known : every 
thing eatable would be tried as food, and only those 
things would eventually be chosen which were found 
by experience to give support to the body. As dis- 
orders arose, attempts would be made to correct 
them by the application of such things as instinct 
suggested, or as experience and reason could sup- 
ply. These substances would be regarded as reme- 
dies, and time and observation would gradually add 
to their numbers. The state of Medicine at the 
present time in many uncivilized parts of the world 
is confined to the knowledge of a few substances, 
which are applied with more or less of sagacity and 
success in the different ailments of the body. Among 
the untutored natives of Africa, Colocynth is a rc- ON THE VEGETABLE MATERIA MEDICA. 
33 
medy which cures many disorders : and Park men- 
tions, that in the cold stage of fevers they place the 
patient in a vapour-bath, which is prepared by 
spreading branches of the Nauclea orientalis upon 
hot wood embers, and placing the patient upon them 
wrapped in a large cotton cloth. Water is then 
sprinkled on the branches, which descending to the 
hot embers, soon covers the patient with a cloud of 
vapour, in which he is allowed to remain till the 
embers are nearly extinguished. Park mentions that 
a profuse perspiration is the consequence, which 
wonderfully relieves the sufferer. 
The Indians of North America give nauseants in 
cases of dislocations, and during the relaxation oc- 
casioned by the medicine they reduce the dislocated 
parts. Other facts might be adduced of the exist- 
ence of medicine as a practical art in many other 
uncivilized portions of the globe ; and an attention 
to this subject is not without its interest and im- 
portance, as it shows us the manner in which the 
science arose in the early rude state of society in 
Europe. If you inquire, however, into the state of 
medicine as it exists in many uncivilized portions 
of the globe, you will find that little is known of 
the nature of diseases or of the action of remedies, 
and that the practice of their physicians is purely 
empirical. You would discover but few instances of 
such correct practice as I have detailed; but would 
meet with charms and ceremonies and inert sub- 
stances, as the means chiefly relied upon in the cure 34 
INTRODUCTORY LECTURE 
of disease. Such absurdities have existed in all 
ages and in all countries; and notwithstanding the 
general intelligence which now pervades all classes 
of society in this country, they exist here. It is 
true that charms and superstitious rites have gene- 
rally passed away ; but many substances yet remain 
attached to physic which were introduced at a time 
when a profound ignorance of anatomy, physiology 
and the nature of diseases existed, and when spe- 
cifics were applied to an unknown condition of the 
body. 
We have an officinal list of medicines in our 
Pharmacopoeia, and I shall generally limit myself to 
it, adding a few substances that are not included in 
it, but which are in general use, and omitting many 
which are altogether useless. 
If we are to consider all the substances included 
in this list as medicines, you will perceive the dif- 
ficulty of drawing a nice distinction between Me- 
dicines and Aliments. Some of them are identical 
with the food of man ; as the acid Fruits, Oats, 
Barley, Honey, Sugar, &c.; while other substances, 
as Ipecacuanha, Tartar-emetic, Rhubarb, are suffi- 
ciently distinct. 
Internal medicines may be regarded as Specific 
Aliments, which remotely or immediately contri- 
bute to the health of the body, taken in small 
quantities. Between some of the more powerful 
ones and certain articles of food there is in some 
particulars a natural affinity. Certain roots which ON THE VEGETABLE MATERIA MEDICA. 
35 
belong to different species of the same genus are 
used as food and as remedies. Jalap and Scam- 
mony belong to the genus Convolvulus, which in- 
cludes the Sweet Potatoe of Carolina, imported 
into this country as an article of luxury for the 
table. But however close the affinity between ali- 
ments and the more powerful medicines, there is 
something generally superadded to the latter which 
forbids its use in large quantities as food, and jus- 
tifies its employment in small quantities as a re- 
medy ;—some active ingredient in which resides its 
virtue as a medicine. 
Between the more powerful medicines and the 
ordinary articles of our food, the difference is so 
wide that we cannot compare them together: but 
when we look over the list of our medicines, and 
find that water, the seeds of several common grains, 
and articles that are daily used as condiments, are 
included among them, any rigorous definition of a 
medicine as distinct from an aliment is impossible; 
nor can we draw a distinction between a Medicine 
and a Poison ; since many of the most fatal poisons 
are the most valuable of our remedies, as Arsenic, 
Lead, Digitalis, Opium, &c. 
What we mean by a Medicine, is a substance 
taken from one of the three kingdoms of Nature, and 
used in disorder and disease to promote immediately 
or remotely the restoration of the natural functions 
and the healthy condition of the body. And by an 
Aliment we mean, a substance taken from the vege- 36 
INTRODUCTORY LECTURE 
table or animal kingdoms, and used in health or in 
disorder and disease, to maintain the strength and 
substance of the body, and repair the waste occa- 
sioned by those secretions which are essential to 
life, or at least to health. 
The connection between Medicines and Poisons 
is so close, that what may be said of one is generally 
applicable to the other, at least to the more power- 
ful of our remedies: but abstractedly considered they 
are in the common acceptation of the words and 
things remotely distinct from Aliments. Yet ali- 
ments have been and are still used as medicines, and 
the difference between them lies in their application 
to different conditions of the body. Hippocrates 
used cold water with success in fevers, and we are 
all sensible that the external and internal use of 
this remedy will cure many simple fevers. 
But if we examine medicines and aliments so as 
to ascertain precisely their composition, we shall 
find in many of our best remedies, substances which 
do not exist in the common articles of our food, 
and which substances exert a peculiar action upon 
the body. 
The food of man, derived from the animal and 
vegetable kingdoms, consists of a few inert proxi- 
mate principles, which undergo the process of di- 
gestion and assimilation; are absorbed into the 
blood, and supply the waste that fluid momentarily 
undergoes in its circuit through all parts of the 
body. In the animal kingdom we find Fibrin, Ge- ON THE VEGETABLE MATERIA MEDICA. 
latin, and Albumen ; and in the vegetable, Gluten, 
Starch, Sugar, Jelly, Gum, and Oils. 
There is no reason to suppose that these sub- 
stances, which seem to have a natural relation to 
our bodies, and which, taken in moderate quantities, 
maintain the integrity of the various functions, do not 
undergo the process of assimilation when they form 
an integrant part of any particular medicine. But 
they must be allied with other substances of an 
essentially different nature, before the remedy con- 
taining them can have any remarkable effect upon 
the bodv. 
The analysis which the articles of the Materia 
Medica have undergone, especially of late years, 
has enabled us to detect many of these peculiar 
substances, on which the specific effects of different 
remedies depend ; and the existence of these proxi- 
mate principles in medicines distinguishes them from 
aliments. Take for instance medicinal roots : We 
find in the Convolvulus Jalap a and C. scammonea 
a purgative quality which does not exist in the C. 
Batatas. Seeds furnish us with similar anomalies : 
The sweet Almond is mild and demulcent, while 
the hitter Almond (both from the same species of 
Amygdalus) affords us Prussic acid. Olive oil is 
largely consumed as an article of diet; but in medi- 
cine we employ other oils, which agree with the 
olive oil in their general characteristics, but which 
differ from it in possessing active qualities available 
in disease, as the Castor and Croton oils. We find 38 
INTRODUCTORY LECTURE 
these peculiar products in many tribes of plants not 
used as aliments; as in the Ipecacuanha, Digitalis, 
Colchicum, &c.; and we obtain them either insu- 
lated, or combined with other ingredients natural to 
the part of the vegetable which furnishes them. We 
thus use powders of seeds, of barks, or of roots, 
infusions of them, of flowers, of woods, or extracts; 
and in some instances we use one part of a plant 
as an article of diet, and another as a medicine. 
The root of Rheum palmatum affords us Rhubarb, 
and the stalks of the leaves an agreeable acid for 
food. We obtain gums, resins, gum-resins, from 
incisions into the barks, stalks, roots, and cap- 
sules of some plants. These insulated proximate 
principles and vegetable preparations holding other 
principles in combination with them, are the mate- 
rials of the Materia Medica ; they are jet apart 
from aliments, as generally differing from them in 
their nature and effects, in their application and 
use; and we are to study their sensible qualities, 
their composition and analogies, and their applica- 
tion to disorders and diseases. 
In this lecture I shall notice the analogies of ve- 
getables, with a view to ascertain how far we can 
discover from them their action on the body. In 
some cases the examination of the colour, odour, 
and flavour of medicines furnishes us with some 
imperfect data on this head. 
In the mineral remedies we obtain no indication 
from colour, with regard to the degree or nature of ON THE VEGETABLE MATERIA MEDICA. 
39 
their action on the body. Corrosive Sublimate, 
Calomel, Lime, and Magnesia, do not differ in this 
respect; but it is of some importance in the vege- 
table Materia Medica. 
Plants of a white or pale colour are generally 
inert, insipid, and mucilaginous ; and in varieties, 
those which bear white flowers are less active than 
those which have flowers more or less tinged with 
colour. 
Yellow is common to many plants ; and though 
it is found in some that are inert, as in the root of 
Liquorice, it generally indicates the bitter principle, 
and is rarely found existing with any free acid. Most 
of the bitter vegetables are of this colour; as Gen- 
tian, Rhubarb, Colocynth, &c. 
Red generally accompanies the acid and astrin- 
gent property. The red fruits and flowers contain 
more or less acid; the petals of the red rose are 
astringent and acid, while those of the white are 
insipid and mucilaginous. The red roots have ge- 
nerally a styptic taste, owing to the presence of 
gallic acid and tannin. 
Green is so generally diffused over the vegetable 
kingdom, that we cannot ascribe any peculiar pro- 
perty to it. It exists with many of an opposite 
nature, as in the Conium and the Mallow. Green 
fruits, however, are generally acid and astringent. 
Blue generally indicates a free alkali. Blue flow- 
ers, and leaves of this colour or of a glaucous hue, 
are active and often poisonous, as the Poppy, Digi- 40 
INTRODUCTORY LECTURE 
tabs, &c. Fungi which emit a blue juice are poison- 
ous. But the epidermis of some fruits, as the Plum, 
has this tint, and forms an exception. 
Black belongs especially to the poisonous plants. 
Those which have stems, leaves, flowers or fruits 
of a dark and dingy aspect, generally have an acrid 
and narcotic quality; as the Belladonna, Hyoscy- 
amus, the Nightshade. There are exceptions, how- 
ever, as the Black Currant. 
The flavour or taste of medicines scarcelv fur- 
nishes us with more precise data as to their thera- 
peutical qualities than the colour. In general, how- 
ever, bodies which are insipid are inert. 
The saline flavour is peculiar to minerals, and to 
a few plants which grow on the sea-shore. The 
substances which possess this flavour are irritating 
to the parts they come in contact with, and possess 
eminently the purgative quality. 
The acid taste is dependent on some free acid 
existing in the substances possessing it. All the 
three kingdoms of Nature furnish acids : but those 
of the mineral kingdom are the most powerful; and 
these in a concentrated state are caustic. 
The vegetable acids are generally refrigerant; but 
they vary in effect proportionate to their concentra- 
tion, as Radical Vinegar; and some are poisonous, 
as the Oxalic Acid. 
A caustic taste is equally produced by strong 
acids and pure alkalies, and some mineral sub- 
stances ; by some vegetable products, as Mezereon, ON THE VEGETABLE MATERIA MEDICA. 
41 
Euphorbhim; and by some animal substances, as 
Cantharides. 
The acrid taste is a modification of the caustic, 
differing in a less degree of intensity. The acrid 
vegetables act as general excitants, as purgatives, 
or emetics. Those of a more powerful character 
act as caustics, and destroy the organization of the 
parts to which they are applied; varying, however, 
as Vesicants or Rubefacients. 
The astringent or styptic taste belongs to mine- 
rals and vegetables; in the latter generally asso- 
ciated with the red colour, and indicating the pre- 
sence of gallic acid and tannin. It exists in Oak 
Bark, Logwood, Kino, Alum, Salts of Iron. 
The bitter taste is more remarkable in vegetables, 
though it is found in some salts; as the Sulphates of 
Soda and Magnesia. It is generally associated with 
the tonic property, but it is common to many sub- 
stances whose actions differ remarkably ; as Gentian 
and Bark, Wormwood and Rhubarb, Aloes and the 
Nux vomica. 
The hot flavour is confined to vegetables, and 
depends on the presence of an essential oil. It 
often is combined with the bitter, and is highly sti- 
mulating. 
The nauseous flavour is allied to the impression 
made upon the organs of smell by those substances 
which possess it. It is not easily defined, as any 
disagreeable taste may be called more or less nau- 
seous. It exists in many of the narcotics, emetics, 42 
INTRODUCTORY LECTURE 
and purgatives, and generally indicates an active 
property. 
The mucilaginous taste indicates the presence of 
gum, of vegetable mucus or fecula, and is inert. 
A sweetish taste is found in some inert sub- 
stances, as in Sugar, Licpiorice; in some laxatives, 
as Manna and Cassia Pulp; and in some mineral 
substances, as Acetate of Lead. 
The odour of medicines also furnishes us with 
some data as to the active properties of medicines. 
Mineral substances are for the most part inodorous, 
but vegetables are most remarkable for the variety 
of their odour. 
The aromatic depends on the presence of a vola- 
tile oil, and is stimulating. To this is allied the re- 
sinous, common to many of the purgatives. 
The foetid odour is supposed to act on the ner- 
vous system, and to indicate an antispasmodic effect; 
as the Assafoetida, and the foetid Gum-resins. 
A nauseous odour belongs to many narcotics, 
emetics, and purgatives. 
Peculiar odours, as that of Camphor, Musk, Prus- 
sic Acid, depend on the presence of these proximate 
principles or modifications of them. 
Where medicines are possessed of a peculiar co- 
lour, flavour, or odour, and these characteristics are 
lost, we may generally infer that the active properties 
of the medicine are diminished or entirely destroyed: 
and you should have tolerably accurate knowledge on 
these points, as you will often be called upon to as- ON THE VEGETABLE MATERIA MEDICA. 
43 
certain the nature of medicines; and unless you 
are aware of their appearances and sensible quali- 
ties, the changes they undergo, you may give an 
erroneous opinion respecting them, and lose the 
confidence of your patient. The Subcarbonate of 
Ammonia, Calomel, Solution of Corrosive Subli- 
mate, Preparations of Iron, Green Powders, Prussic 
Acid, Deliquescent Salts or those which effloresce, 
Tinctures, Infusions, and Decoctions, are perpetually 
liable to changes ; and if you are not prepared for 
them, you may be alarmed, and excite alarm in others 
prejudicial to the health and life of your patient. 
We have a much surer guide to the knowledge 
of the properties of vegetable substances, in the 
analogies of the plants which furnish them. The 
observations I shall make upon this interesting sub- 
ject are entirely copied from a work of Decandolle’s 
on the Medicinal Properties of the Natural Families 
of Plants; and I would wish you particularly to refer 
to it for other details than those I offer to your 
consideration. There is some relation between these 
properties and the external forms of plants. Know- 
ing, for instance, the virtues of any one plant, ana- 
logy would lead us to infer a like virtue in another 
allied to it in form and habit. Those plants which 
possess similar botanical characters, which agree in 
structure, and which are consequently grouped to- 
gether from their affinities, generally contain simi- 
lar proximate principles, more or less modified; and 
as their virtues depend upon these principles, their 44 
INTRODUCTORY LECTURE 
action must in many respects be similar, though it 
may be modified from some peculiarity of composi- 
tion and diversity of combination in these principles. 
These proximate principles are the products of 
nutrition ; and as this function depends on the 
structure of the different organs of plants, there 
must be some relation between this structure and 
the products and properties it gives rise to. This 
relation has been presumed in many instances from 
theory, and confirmed by observation and expe- 
rience. Analogy has led many individuals, who 
were furnished with precise knowledge of the vir- 
tues of known plants, and an acquaintance with the 
principles of botanical arrangement, as well as the 
general structure of vegetables, to make use of 
plants that were otherwise wholly unknown to them, 
for the purpose of obtaining their therapeutical or 
diatetic effects, by observing their similarity' to 
plants they were familiar with, and whose proper- 
ties had been ascertained by experience. 
Forster, in his voyage with Captain Cook, met 
with a plant of the natural family Crucifer a, and 
employed it successfully as an Antiscorbutic. La- 
billardi&re, who went in search of La Perouse, used 
several plants as Pot-herbs for his crew, because he 
observed their affinity to those in common use in 
Europe, though specifically distinct and before un- 
known. Nuthall, in his Travels in the Arkansa ter- 
ritory, in the southern part of North America, du- 
ring which he passed through the extensive savan- 45 
ON THE VEGETABLE MATERIA MEDICA. 
nahs peculiar to the banks of the large rivers in that 
country, was attacked with Ague, which he cured by 
using a decoction of a new species of Eupatorium, 
a genus remarkable for its bitter principle. 
This view of the relation between the medicinal 
virtues and structure of plants has been much at- 
tended to of late years, and has been productive of 
more order and method in our description and ex- 
hibition of medicines ; and it has also tin own li^ht 
upon the natural classification of vegetables. 
In the best known and most natural families we 
find the most remarkable agreement in form and 
property. Thus the Crucifer,at, examples of which 
you have in the Mustard and the Horse-radish, have 
an acrid volatile oil possessed of highly stimulating 
qualities. This principle is concentrated in the seeds 
of the Mustard and the root of Horse-radish, and 
both have been used as rubefacients. Sinapisms 
derive their name from the genus Sinapis or Mus- 
tard. We employ the Sinapis nigra in Europe, but 
in India they use the S. dichotoma and ramosa. 
This acrid property is less remarkable in som. of 
the genera of this family, and we use them as fresh 
condiments. In others it is combined with muci- 
lage and a nutritious saccharine matter; and these 
are most extensively employed as aliments, as in the 
Cabbage and Turnip. Art is employed in the cul- 
ture of others, to lessen or destroy their pungency; 
as in the Sea Kale, a plant which was considered 
among the Romans as a gross article of food, and 46 
INTRODUCTORY LECTURE 
used exclusively by the common people, for want of 
the means of obviating its natural flavour by our 
peculiar mode of cultivation. In others we use the 
first shoots of the stem, before their flavour is de- 
veloped ; as in the Brocoli and Cauliflower. 
The seeds, however, of all the plants in this ex- 
tensive family contain the acrid volatile oil, and are 
stimulating and diuretic. 
The ancients, who had no systems, were evidently 
of opinion that those plants which had an agree- 
ment in form, possessed similar properties, from the 
order in which plants follow in their works. Ca- 
merarius in 1699 first expressed the opinion, and 
it has been generally concurred in by all botanists 
since. The most uncultivated mind, as far as pre- 
cision of scientific knowledge was concerned, would 
instinctively look for Turpentine in the Pines of 
any portion of the globe, and for Tannin in the 
Bark of Oaks. 
The chemical composition is a clue to the know- 
ledge of the properties of mineral medicines; but 
the ultimate analysis of the proximate principles of 
vegetables is of little use. The knowledge, how- 
ever, of these proximate principles themselves is 
of the first importance, both with regard to their 
source and properties. They are the products of 
the organization or structure of the plant which 
affords them. Two plants of different structure 
growing in the same soil will produce different pro- 
ducts ; while plants of a similar structure, growing 47 
in different soils, will form similar products. The 
structure of the nutritive organs influences the na- 
ture of these products. If you put a seed of St. 
John’s Wort in the same soil with a seed of Nettle, 
the one will develop two leaves, with a volatile oil 
embedded in its substance, and the other, leaves 
rough with protuberances, bearing a caustic fluid in 
them. Different parts of the same plant differ in 
structure and in product, just as we see in animals. 
Now the natural classification of plants is the ar- 
ranging in families those which have a similar struc- 
ture in the flower and fruit: and as plants so ar- 
ranged agree in structure, it is natural to expect that 
their products will be similar. 
That this is the case is proved by the instinct of 
animals. If an animal rejects one plant as food, it 
generally rejects all the plants of the family. 
Insects generally have but one kind of food, and 
are confined to one species: but if they feed on 
more than one species, they seldom or never go 
beyond the species of one genus. The Silk-worm 
feeds on the leaves of the Mulberry. You know it 
is domesticated in many countries, but wherever 
taken it must be fed on the species of the genus 
Morus or Mulberry; and we find it feeds on the 
black, the white, the red Mulberry, the Mulberry of 
India and of Tartary,—all distinct species. 
Sometimes we find insects which feed on plants 
of different genera; but even in this case they sel- 
dom or never attack plants belonging to a different 
ON THE VEGETABLE MATERIA MEDICA. 48 
INTRODUCTORY LECTURE 
family. The Cantharis feeds on the Ash, the Lilac, 
the Privet, and the Olive,—all genera of one natural 
family; hut it is never found on the Jasmine, be- 
longing to a different family, though this is culti- 
vated with the other trees. The Sphinx of the Privet 
feeds also on the Ash and the Lilac. The Butterfly 
of the Cabbage feeds on the Radish and Gillyflower. 
These facts are strong probabilities that plants of 
the same family have similar juices, and that the 
juices of genera associated in families have similar 
properties. 
We observe the same uniformity of attachment 
to plants of the same family in the parasitical Fungi, 
which derive their nutrition from the living sap. 
The Uredo of the Rose will attack a foreign species 
of rose if naturalized in our gardens, but not a plant 
of any other family. 
This affinity between some families of plants and 
insects is so evident, that we find foreign trees na- 
turalized in Europe, which belong to families not 
naturally associated with the plants native of Europe, 
are never attacked in the country of their adoption 
by the insects which infest our trees. Thus the 
Tulip-tree of North America, the Melia Azedarach 
or Pride-of-India are not disfigured by the depreda- 
tion of insects in our gardens, when the native trees 
are more or less stripped of their leaves. I have 
repeatedly admired at the close of summer the fresh 
and entire foliage of the Salisburia Adiantifolia cul- 
tivated in North America, when most of the trees ON THE VEGETABLE MATERIA MEDICA. 
49 
native of that country have lost their beauty by the 
ravages of the caterpillars which infest them. 
Experience also proves the resemblance between 
the properties and forms of plants. It was formerly 
supposed that Bark was the product of one species 
of Cinchona, hut we now know that it is obtained 
from nearly all the species of this genus. Rhubarb 
was supposed to be the product of one species of 
jRheum, but it is afforded by three or four. So Opium 
may be obtained from several Poppies ; Turpentine 
from all the Pines ; Gum Arabic from several Aca 
cias. We find that all the Mallows are emollient 
and demulcent ; all the Gentians bitter and sto- 
machic ; the Aconites, poisonous ; the Hellebores, 
purgative ; and the Euphorbia, acrid and caustic. 
If we find a property strongly marked in the 
plants of one genus, we are almost sure to find a 
similar property, more or less modified, in the genera 
closely allied to it. Thus the Pinckney a of North 
America, allied to Cinchona, is febrifuge. Many of 
the Rumices, allied to Rheum, are purgative; the 
Chamomile and Tansy, allied to Wormwood, are 
bitter and anthelmintic. 
The property is sometimes so remarkable that it 
is found in all the plants of a family. All the 
Grasses have a farinaceous seed, and a sweet mu- 
cilaginous sap in their culms or straw,—whence 
their use as food for man and herbivorous animals. 
Voyages and travels have shown that nations re- 
mote from each other have used from time imme- 50 
INTRODUCTORY LECTURE 
morial plants of the same genus or family for simi- 
lar purposes, either as food, or in medicine and the 
arts. 
But we find, occasionally, striking anomalies; 
sometimes meeting with a poisonous principle in one 
species associated with principles of an opposite 
character, in another species closely allied to it. 
The deadly Hemlock and Cicuta are related to the 
Carrot and the Parsnip ; the Sweet Potatoe to the 
Scammony and Jalap ; the common Potatoe to the 
Nightshade ; the Colocynth and Elaterium to the 
Gourd and Melon. 
These anomalies, however, are not to disprove the 
facts I have already mentioned, though their ex- 
istence makes it necessary to establish some rules 
for our making a comparison between the form 
and properties of plants. 
All classification is founded on a knowledge of 
species. Those species which have a certain num- 
ber of common characters are grouped together 
into distinct genera. These genera are grouped 
into families ; and these families into classes. Now 
this arrangement of plants into species, genera, fa- 
milies and classes, has been attempted in such away 
as to form a continued series; on the supposition 
that all organized bodies form a chain, each link of 
which is distinct, but each succeeding one agreeing 
in some points of resemblance with that which pre- 
ceded. But this idea, however beautiful, cannot be 
susceptible of proof until we are perfectly acquainted ON THE VEGETABLE MATERIA MEDICA. 
51 
with all the plants of our globe; for the ignoranee of 
any one plant will occasion a break or interruption 
in the series. Decandolle ingeniously remarks, that 
some idea of a natural classification as it stands in 
the present state of our knowledge, may be had 
by imagining this affinity of plants compared to the 
appearances of our Earth on a map. The species 
are the towns; the genera are the provinces or coun- 
ties ; the families are the empires ; while the classes 
are the quarters of the globe; and those plants which 
cannot be referred to any place in the system are 
the islands far removed from the continents. On 
examining a map, you would perceive that in some 
empires or provinces the towns are near each other, 
while in others they are remote. The same thing 
is observable in a natural classification: and where 
we see an apparent interruption in the series, the 
separation depends either upon our ignorance of the 
intermediate plants, or upon Nature having left a 
void or break in the vegetable scale, just as in certain 
parts of the globe she has left uninhabitable sandy 
or rocky deserts. The Grasses, the Cruciferce, form 
a continuous chain, and are intimately allied in form 
and property, resembling the clustering towns of a 
thickly settled province ; while the Rutacea and the 
Urticece present anomalies or breaks in the chain, 
like those districts which are intersected by desert 
plains or inaccessible mountains. Where we do not 
find anomalies in families,the plants composing them 
agree in form and property ; and where these ano- INTRODUCTORY LECTURE 
malies exist, we find contrasts more or less remark- 
able, like the inhabitants of the thickly settled coun- 
tries which present a uniformity of manners and habits, 
unlike those of the thinly peopled and barren districts. 
In geography we sometimes find an insulated town or 
distant island united for the sake of convenience to 
a neighbouring province : so in a natural classifica- 
tion we occasionally find a plant attached to a genus 
or family to which it is barely allied, for the purpose 
of avoiding too great a multiplicity of divisions. 
In these cases the difference of property depends 
upon difference of structure. 
It often happens also when a plant differs re- 
markably in its properties from the family in which 
it is placed, that it is found on a closer observation 
to belong to another family. The Menyantlies tri- 
foliata, which is remarkable for its bitter property, 
was for a long time associated with the Primulacea, 
and presented a remarkable anomaly; but Ventenat 
has shown that it really belongs to the Gentianea, 
in which we find the bitter property predominant. 
Many of the other anomalies will probably disap- 
pear as the structure of the plants which present 
them is better understood. 
But many of these anomalies are only in appear- 
ance. They depend upon certain organs and their 
products existing in one plant which are not found 
in the plants associated with it. For instance, 
we find the nutritious and feculent potatoe closely 
allied to the Nightshade and Bittersweet; but this ON THE VEGETABLE MATERIA MEDICA. 
53 
anomaly depends on a part existing in the potatoe 
which is not found in the other two, and in our using 
different parts of these plants. In making our com- 
parisons between plants, we ought to draw the re- 
semblance between the organ of one, and the cor- 
responding organ of another; and if in one we find 
an organ that does not exist in another, here our 
comparison must, with respect to the product of that 
organ, end. If we attend to this rule, we shall never 
compare the nutritious tuber of the Potatoe—a re- 
servoir of fecula,—-with the poisonous berries of the 
Nightshade, or the stalks of Bittersweet. 
The extensive natural family of the Umbelliferm 
presents most remarkable anomalies; and I refer you 
to Decandolle’s ingenious reasoning upon them. 
This family presents us with the fetid gums, Assa- 
foetida, Galbanum, &c. &c. products obtained from 
incisions into the root;—with the Carrot and Pars- 
nip, in the entire roots of which we find a mild nu- 
tritious food; with the Conium, the leaves of which 
afford us a narcotic principle ; and lastly, with the 
Dill, Anise, Carraway, the seeds of which afford 
us a stimulating volatile oil. This last principle 
existing in an essential organ is more or less re- 
markable in the seeds of all the family. 
The same plant differs in the products of its dif- 
ferent parts. We need not wonder therefore that 
the berries of one species differ from the tubers of 
another, or that the roots of the Carrot and Parsnip 54 
INTRODUCTORY LECTURE 
are adapted for food, while the leaves of the Hem- 
lock are poisonous. 
It is evident also, if some plants of a family pos- 
sess an organ which does not exist or is imperfectly 
developed in the others, that the peculiar properties 
afforded by this organ cannot exist where the organ 
is absent. Thus the laxative property of the 
Cassia Fistula and the Tamarind is not found in the 
other Leguminoscp., because the pulp itself which 
affords the property is absent in them. 
If the property resides in any one organ which 
is essential to the family, we find little or no 
variation in the property of all the plants com- 
posing the family. You see this in the farina- 
ceous seeds of the Grasses and in the seeds of the 
Umbelliferce, all of which possess a stimulating vo- 
latile oil. 
If similar properties are found in associated plants, 
but seated in different organs, the cause of this ano- 
maly will be found in the natural relation which exists 
between the apparently different parts. Thus the 
bulbs of some Liliaceous plants afford a fecula like 
the trunks of the Palms; while the bulbs of other 
species possess a purgative quality, like the stem and 
leaves of the Aloe. Now this apparent anomaly is 
removed on a closer examination of the true nature 
of the part we call a Bulb, which is commonly con- 
sidered a root, but which Decandolle thinks is more 
naturally allied to the stem. A bulb has three dis- ON THE VEGETABLE MATERIA MEDICA. 
55 
tinct parts ; radicles which are the true roots, scales 
which are abortive leaves, and a central portion which 
is the real stem. That this is the fact is apparent 
from those plants which have bulbs having no stem, 
except the central portion enveloped by the abortive 
leaves or scales ; and those which have a stem have 
no bulb. 
There are certain circumstances which remark- 
ably influence the properties of the same plant; as 
the situation in which it grows, whether dry or 
moist, dark or exposed to light. The Heracleum 
sphondyliujn of our meadows is eaten by cattle ; but 
if it grows in a swamp it is poisonous. The Celery 
in marshes is an acrid poison; but cultivated in a 
dry soil and planted deep in the earth it becomes a 
mild and nutritious vegetable. Now if the same 
plant offers these anomalies, it is not to surprise us 
that different plants allied to each other should in 
different situations and under different circumstances 
possess different properties. 
If we study the chemical composition of the pro- 
ducts of vegetables, we shall find that certain prox- 
imate principles are not liable to much variation, 
while others are easily affected by a variable pro- 
portion of their ultimate principles. Gum, fecula 
and resin are generally fixed and constant; but the 
gum resins are liable to variation, because the 
proximate principles composing them vary in their 
proportions ; sometimes the gum being in excess, 
at others the resin. Now gum resins abound in 56 
INTRODUCTORY LECTURE 
the Umbelliferce and the Convolvulaces, families in 
which the anomalies are most remarkable. 
A solution of some of the anomalies we meet 
with is found in the natural transition of some of 
the proximate principles of plants into other proxi- 
mate principles. Thus acids and mucilage seem to 
he naturally changed into sugar, sugar into starch, 
fixed oil into wax, volatile oil into resin,—from a 
change of proportion in the ultimate elements which 
compose them. Green unripe fruits are sour, from 
the presence of an acid; and they become sweet as 
they ripen, from the formation of sugar. The Co- 
nifers afford resins abundantly ; but some of them 
afford a volatile oil, that is, a product not oxidated 
sufficiently for its conversion into a resin. 
Plants of different families appear to afford simi- 
lar properties. We have for instance the bitter, the 
astringent, and the narcotic principle in several fa- 
milies: but these principles differ in each family. 
How different is the bitter of Wormwood from that 
of Gentian, of Colocynth, of Aloes, or Bark ! How 
different is the narcotic principle of Opium from 
that of Hyoscyamus and the Conium ! 
A slight difference in the mode of preparation 
of medicines or products will affect their proper- 
ties. We could not draw any conclusion as to the 
real properties of the vine, from the products we 
obtain from it. What affinity is there between the 
juice of the fresh grape, and wine, vinegar, brandy, 
and alcohol ? and yet all these are obtained from it. ON THE VEGETABLE MATERIA MEDICA. 
57 
On the other hand, a similar mode of preparation 
elicits similar properties from plants which have an 
affinity to each other. Jussieu from analogy in- 
ferred a similar property in the seeds of the Galium 
Aparine to that of Coffee, and he obtained a like 
aroma by preparing them as we prepare coffee. 
We have given rise to.some anomalies by our 
mode of exhibiting and classing medicines. Though 
the practice of Physic rests as a basis upon Physio- 
logy, Medicines were classed before any precise 
ideas of their mode of action was arrived at; and 
our classification rests not upon their mode of ac- 
tion, but the effects they produce under certain 
circumstances. At first almost all medicines were 
regarded as specifics ; but as the science advanced, 
physicians generalized the effects of their remedies, 
and at the present day we have scarcely any spe- 
cifics at all. 
This classification leads to two errors with re- 
spect to the application of Botanical analogy to 
medicines*. 
The one is, that we call medicines, whose mode 
of action is similar, under different names, and ar- 
range them in different classes : and the other arises 
from our giving the same name to medicines which 
are really distinct in their mode of action, merely 
because they produce similar effects. 
The first error arose from certain medicines being 
* See Decandolle’s work. 58 
INTRODUCTORY LECTURE 
at first applied to one organ only. Thus Tobacco 
is sternutatory, sialogogue, emetic, or purgative, as 
it is applied to stimulate the nose, the mouth, the 
stomach or bowels; and yet its mode of action is 
the same in all, though the effects differ. Squill is 
another instance, being emetic, purgative, diuretic, 
or expectorant. Now as the same medicine pro- 
duces different effects, according as it is applied to 
different organs and according to the pathological 
condition of the patient,—can we be surprised that 
different plants of similar structure should appear 
to possess different properties ? Squill would seem 
to explain the anomalies of the Liliacece; for in some 
degree it has the purgative qualities of Aloes and 
the diuretic qualities of the Garlick and Onion; and 
the properties of them all appear to be a modifica- 
tion of a stimulant property. Now many of the ex- 
isting anomalies may be explained by the different 
application of the same property. 
The same medicine produces different effects in 
different doses. Wine and Opium in small doses 
are stimulant, in large narcotic. Rhubarb in small 
doses is tonic, in large purgative. Ipecacuanha in 
small doses is purgative, in large emetic. Now if 
the same substance produces effects so different in 
different doses, it is natural that medicines obtained 
from analogous plants should differ, from the differ- 
ent degree of concentration of their principles. 
With regard to the second error, viz. that we 
give the same name to medicines, which are really ON THE VEGETABLE MATERIA MEDICA. 59 
distinct in their mode of action, merely because they 
produce similar effects. We see this in Diuretics 
and Diaphoretics. The increase of the flow of 
urine appears to be a simple effect; yet it is pro- 
duced by at least four different means: either by 
augmenting the mass of fluid in the body; by sti- 
mulating the kidneys, or the body generally; or by 
checking the perspiration. Water, Digitalis, Squill, 
and cold, are examples of this similar effect pro- 
duced by different causes. The same occurs in Dia- 
phoretics. Some augment the fluid to be perspired; 
others stimulate the vessels of the skin ; others in- 
crease the velocity of the circulation; and others 
raise the general temperature. We should therefore 
pay particular attention to the mode of action, rather 
than to the ultimate effects of remedies; and until 
we know the precise mode of action, the objection 
against the analogy of form and property, derived 
from the circumstance that plants of different fa- 
milies produce similar effects, cannot have much 
weight. 
Now with regard to the examples of this agree- 
ment in the form and property of plants, I could 
give you many instances; but I will only refer to a 
few that will be at once familiar to you. The Gra- 
minece or Grasses, require no illustration. The 
Wheat, Rye, Barley, Oats, Rice, Indian Corn, the 
Millets of India, constitute the wealth of the agri- 
culturist; and bread has been emphatically called the 
Stab of Life. We employ these grasses in agricul- INTRODUCTORY LECTURE 
ture, because their seeds are the largest and the most 
productive: but all grksses produce farinaceous 
seeds; and the herbivorous animals are fed upon 
them, and on the nutritious juices of their stems 
and leaves,—either fresh, as grass, or dried, as hay. 
The Conifers, which include the Pines, the Firs, 
the Larch, the Juniper, as you are all aware, re- 
semble each other in form, and abound in tur- 
pentine and resin. The y which in- 
clude the Ranunculus, or the Yellow Buttercup of 
our meadows and fields, the Anemone of our woods, 
the Clematis and Peony of our gardens, the Helle- 
bore, the Aconite,—are all acrid and poisonous. The 
Solanece, which include the Belladonna, the Night- 
shade, the Hyoscyamus, the Tobacco, the Stramo- 
nium, are acrid narcotics. 
I have dwelt thus long on the subject of the re- 
lation existing between the form and properties of 
plants, because it is one of the most interesting and 
instructive connected with the Materia Medica. It 
gives us the most extensive ideas on the properties 
of vegetables; for from the precise knowledge of 
the virtues of any one plant we may form tolerably 
accurate conclusions as to the virtues of those al- 
lied to it. It thus aids the mind in its researches, 
and by furnishing us with a leading principle in our 
investigations, simplifies them, and guides us through 
the labyrinth of nature. We have only to ascertain 
the general properties of any plant, and to be fami- 
liar with the systems of classification, to appreciate ON THE VEGETABLE MATERIA MEDICA. 
the advantages of the known vegetable world in 
its application to medicine, to diet, or the arts. 
But to pursue this study, an acquaintance with the 
structure of vegetables, and the celebrated systems 
of Linnaeus and Jussieu are indispensable; or, in 
other words, you must become Botanists. 
I wish I could excite in your minds a conscious- 
ness of the extreme facility of the rudiments of this 
most beautiful and enchanting of all sciences, be- 
cause I should remove the apprehension you may 
feel of its requiring laborious study; and you 
would then perceive that its pursuit is compatible 
with the active duties of your profession. The 
science, in its widest extent, is one of the most ela- 
borate, and requires patient investigation and pro- 
found observation; for it embraces not only the 
external forms and structure of plants, but their 
physiology, and the functions of their various parts : 
and some of the most highly gifted men of all ages 
have devoted their great talents to its pursuit. No 
name among the many of these great men will have 
such influence with you as that of Haller, whose 
fame as a Botanist is only secondary to his celebrity 
as an Anatomist and Physiologist: and it is only 
necessary to refer to his Letters to Linnaeus, to see 
how much his heart and mind were interested in his 
botanical pursuits. In one of them he says, “ I 
have not done much in Botany of late, except my 
journies, and the examination of characters in my 
garden. Anatomy is my chief occupation combined 62 
INTRODUCTORY LECTURE 
with Physiology. To these I am obliged to devote 
the greater part of the year. Your happier fate 
spares you such interruption to your pursuits. But 
if ever I can return again to my own country, I shall 
seek no other pleasure than Botany. To that, in 
the investigation of what Switzerland produces, I 
hope to dedicate the remainder of my life.”—In 
another letter, after wishing Linnaeus health for his 
botanical pursuits, he says, “ My studies and en- 
gagements of a different nature draw me unavoid- 
ably aside, but my inclination always leads me to 
the charms of Flora. To Botany I wish to devote 
my leisure, my old age, and my fortune.” 
It is remarkable, that many of the most active 
Physicians have been the most distinguished Bo- 
tanists ; indeed Cuvier in his Eloge upon the Sci- 
ences, ascribes their origin and progress in the 
earlier ages to the investigations of medical men. 
The necessity of their cultivation for the perfec- 
tion of Physic is still as imperative upon us as 
upon those who first called them into being; for 
we derive our means for the cure and prevention of 
diseases from the three kingdoms of Nature : and if 
I may be allowed to speak from my own partial and 
most imperfect experience of the advantages of the 
knowledge of Botany, I would say,—there is no study 
more instructive to the Physician than that of Plants, 
and certainly none which brings with it more de- 
lightful consolations under the trials and distresses 
that are so peculiar to the practice of Medicine. I ON THE VEGETABLE MATERIA MEDICA. 
63 
would not, however, exalt Botany to the prejudice 
of the other sciences ; for they each form a link in 
the great chain of knowledge, and mutually depend 
upon each other. But when we look abroad through 
Nature, and see the profusion,the variety,the beauty, 
and the utility of the vegetable world,—can we per- 
mit ourselves, as rational beings, to exist and allow 
the means of observation and instruction which we 
possess, to lie unimproved through life, by passing 
with indifference those lavish materials for know- 
ledge and happiness, furnished by the vegetable 
creation ? Can we be indifferent to the source of 
our most essential comforts, and of many of the 
most interesting productions of Nature, which fur- 
nish us with the instruments of our knowledge, and 
the materials of our usefulness ? 
I need not speak of the beauty of the vegetable 
kingdom ; of the hue of the rose and of the violet, 
and of their exquisite perfume; of the refreshing 
verdure of our fields; of the foliage of our woods, 
and the grace and majesty of our forest-trees ;—for 
these varied attractions are perceived and felt by 
all: and the pure happiness which results from 
their contemplation, is at the same time the evi- 
dences of their beauty, and of our just apprecia- 
tion of the charms spread so lavishly abroad to de- 
light the eye and gladden the mind and the heart of 
man. 
But I would for a moment direct your attention 
briefly to the uses of vegetables; and I would ask 64 
INTRODUCTORY LECTURE 
you, if in the pursuit of knowledge, directed to 
whatever ultimate aim,—you can neglect the cul-„ 
tivation of the science of Botany, taken in its 
range, as including the history of the materials so 
benevolently scattered over the globe for the use of 
all animated creation ? 
Whence is it that we derive the largest portion of 
our food, but from plants, found in some instances 
in the seed; as in the Wheat, the Oat, the Rye, 
the Barley, the Rice, the Maize, the Cacao, the 
Coffee ; the various kinds of leguminous plants, as 
Peas and Beans; the oily Kernels of stony fruits, 
as the Almond, the Hickory, the Hazel, and the 
Cocoa-nut;—or in other instances, in the entire 
fruit, as the Apple, the Peach, the Plum, the Cherry, 
the Grape ; the infinite variety of Berries ; the de- 
licious fruits of tropical climates, as the Pine-apple, 
the Orange, the Lemon, the Fig, the Date, the 
Pomegranate, the Lotus of Africa; the various 
Gourds and Melons,—one of which, the succulent 
Water Melon of sandy countries, contains an abun- 
dant fluid to quench the burning thirst of the African 
and the Asiatic; the Plantains, the Bananas, and 
the Bread Fruit; all of which, in the different coun- 
tries in which they are indigenous, give food, and 
strength, and happiness to millions of human beings ? 
Some plants afford in their leaves the most essen- 
tial articles of luxury: witness the Tea-plant and 
the Tobacco, the Betel of Asia, and the Coca of 
Peru, vegetables which have a most mysterious ON THE VEGETABLE MATERIA MEDICA. 
65 
influence over the nervous energy of all nations, 
and which are resorted to, especially, by those ex- 
hausted and debilitated by labour, fatigue and watch- 
fulness, and in which even the philosopher finds a 
solace that nothing else can afford. 
Whence is it that we obtain our Wine ?—one of the 
innocent sources of our social happiness and con- 
viviality,—the true water of Lethe!—under whose 
influence the miserable find joy, and the forlorn arc 
blest with the visitations of hope, and in which the 
poor find the momentary oblivion of their many 
hardships and cares ? In what age or clime have the 
unfortunate failed to find a solace, or the pros- 
perous an increase of enjoyment from the use of 
spirituous liquors ? I do not allude to their abuse ; 
and need not repeat here the stale dogmas of de- 
claimers against the use of ardent spirits : but I 
allude to the exhilarating feelings which follow their 
moderate stimulus, praised and sung by the Poets 
of all times. The source of these liquors is al- 
most exclusively found in the Vegetable Kingdom ; 
though from the bounty of Nature, in those sterile 
regions where the earth is not enriched with the 
fruits of the more favoured climes, an intoxicating 
beverage is made from the milk of some animals ; 
as the koumiss of the Tartars, from the milk of the 
mare. In the Hebrides a similar spirit is obtained 
from the milk of the ewe. With these exceptions, 
all ardent spirits are obtained from vegetables. 
In Europe we make Wine and Brandy from the 66 
INTRODUCTORY LECTURE 
juice of the Grape ; Porter, Ale, and Alcohol from 
Barley; Cider and Perry from the Apple and the 
Pear. The West Indian and the American obtain 
their Rum from the Sugar-cane. The African pro- 
cures his Wine from a species of Palm : while the 
natives of some of the islands of the Pacific Ocean 
extract a spirit from a root of one of the Peppers. 
To what innumerable uses do we apply the Woods 
of Trees, and what important consequences result 
from their various use ? as the construction of houses 
and of furniture ; of the implements of our arts, so 
variously diversified, and so essential to the very 
existence of man in a civilized state ; the construc- 
tion of ships, by the aid of which the most remote 
quarters of the globe are brought as it were to- 
gether, and all the different races of man form one 
common family, busied in the interchange of thought 
and of affection, and in the commerce of the pro- 
ductions of Nature and of Art. 
In the many afflictions incident to human nature 
from disease,—how do we allay pain, quiet irritabi- 
lity, induce sleep, restore the natural functions, and 
bring back the blessing and the beauty of health to 
the wan and faded aspect, but by the use of reme- 
dies that are principally obtained from the Vege- 
table Kingdom! 
If we were to take a rapid view of medicines, we 
should find that by far the greater number of the 
safest and best of our remedies are derived from 
plants. Opium, Bark, Ipecacuanha, Rhubarb, Sen- ON THE VEGETABLE MATERIA MEDICA. 
67 
na, Colchicum, Aloes, Castor-oil, Hyoscyamus, Bel- 
ladonna, Digitalis, Gentian, Columbo, the Alkaline 
Carbonates, the Supertartrate of Potash, the Acetic, 
the Citric, and the Tartaric Acids, are a few of these 
vegetable remedies ; and they are the most useful, 
because the most extensively applicable. 
From the Mineral Kingdom we obtain no nar- 
cotic, no bitter principle, no purgative, that can be 
habitually used. I do not mean to disparage the 
products of the Mineral Kingdom; for no one can 
be ignorant of the importance of some of them: as 
Calomel, the Protoxide of Mercury, the Arsenical 
Solution, Magnesia and its Sulphate, the Tartrate 
of Antimony, the Nitrate of Silver as a caustic, the 
Sulphate of Zinc, the Sub-acetate of Lead as a lo- 
tion. These are the most important of the mineral 
remedies; but they are far outnumbered by the 
products of the Vegetable Kingdom. 
I would again ask you,—if with these claims to 
your notice, you can pass with a superficial glance 
over the Vegetable Kingdom ? The meanest weed 
that you trample under foot has a symmetry and 
a contrivance that was devised by no human intel- 
lect ; and in studying its organization, you peruse a 
page in the great book of Nature, the production of 
that pervading mind which formed, and governs, and 
guides the universe. In perusing this volume of 
Nature, you will arrive at a knowledge which no 
human means can afford ; for you will look through 
the works of Nature to their Author : while the pas- 68 
INTRODUCTORY LECTURE 
sions and prejudices of your being will be put at rest; 
and in their room will come those perceptions of 
beauty and of utility, which will refine your taste 
and call forth the germs of that virtue, which is 
permitted to blossom in this world, but the fruit of 
which is to be reaped hereafter. 
I do not consider this language or these views 
unsuited to the present occasion; for it is my duty 
to excite in you an ambition for the acquisition of 
knowledge, and I know of no limits to its range. 
If there be any of you who confine your desires to 
the mere rudiments of a common medical education, 
and who have no wish to extend your knowledge 
beyond the names and uses of medicines, I confess 
to such I may appeal in vain. But these individuals 
should remember, in the present enlightened age, 
distinguished above all others by the profusion of 
intelligence scattered amid the humblest ranks of 
society, that they are most likely to be passed in 
the career of emolument and fame; and they should 
remember, when actively engaged in the duties of 
their profession, that regrets will then come too 
late; for they will be on the great theatre of the 
world, and their more accomplished competitors 
may be outstripping them in the game of life. 
It is no answer to tell me that the knowledge I 
recommend is not immediately available in the prac- 
tice of medicine. It is at all times serviceable to its 
possessor; for it increases his usefulness, it makes 
a part of his own independent enjoyments, and it ON THE VEGETABLE MATERIA MEDICA. 
secures him the respect and confidence of the wise 
and good. Every individual engaged in the pursuit 
of a learned profession, should feel an ambition 
of having his general knowledge proportionate to 
his professional accomplishments : and you may be 
assured that your reputation, both with regard to 
general information and the manners of gentlemen, 
will materially influence your success in life. 
But there is a higher inducement to the pursuit 
of knowledge than the mere physical advantages 
that may ensue from it. It is that of holding an 
enlarged sympathy with the wants, the pursuits, and 
the enjoyments of mankind in all regions, and in 
familiarizing yourselves with those productions of 
nature which are the sources of happiness to mil- 
lions of human beings. It is also that of cultivating 
the talents bestowed upon you for your own good 
and for the good of others, and of acquiring a taste 
for the beauties of nature, which sheds a charm 
round the genius and the affections of the most 
distinguished men. 
There is a mysterious communion between the 
mind and heart of man and the sights and sounds 
of natural objects. A voice, descending from Hea- 
ven and borne upon the breath of morn, is heard 
along the enamelled mead or through the mazes of 
the dark forest, which penetrates to the sources 
of our thoughts and affections, and which kindles 
a spirit of devotion to light and warm our own 
bosoms, to be thence reflected upon all around us. 70 
INTRODUCTORY LECTURE ON THE VEGETABLE MATERIA MED1CA 
Listen to its instructions in the delightful soli- 
tude of your occasionally secluded hours, far from 
the contaminating influence of worldly ambition; 
and you will return to society with feelings better 
adapted to the discharge of your duties there, and 
in the possession of a mean for happiness which 
no adversity can rob you of, and with a refinement 
of mind which no prosperity can vitiate. 
THE END. 
PRINTED BV RICHARD TAYLOR, 
SHOE-LANE.