188 THE IMPORTANCE OF THE STUDY OF BOTANY TO MEDICINE. 
bark, the root, the herb of the same species, gathered at different 
seasons, do not contain the same principles; this, at one period, is an 
active medicine, at another, next to useless; and besides, if chicanery 
will practise upon the immediate necessaries of life, the commerce of 
medicine is not likely to be wholly free from its impositions. 
Experience has shown that not only the imported articles of 
materia medica, but even those of home growth, are often the vehicles 
of fraud that renders negative, if it does not totally subvert, the 
intentions of the adviser. The leaves of the senna are mingled 
with those of several other plants, of less valuable and of deleterious 
quality; the lithontriptic and diuretic properties of the uva-ursi, are 
supplanted by the simple astringency of the vaccin. vit. id.: and even 
the bark of the tree of life itself—the highly prized cinchona—is 
vilified, and its restorative virtues abused, by the cupidity of the 
fraudulent and grasping trader, who scruples not to impose upon his 
ignorant customers that of other trees of inferior worth. Now even 
in the state in which these and numerous other vegetable substances 
are submitted to the inspection of the faculty, a knowledge of botany 
will often afford a test of no small importance in the choice of an 
article which a person proposes to prescribe and administer, where his 
fortune, and, what is more valuable to a medical man, his reputation, 
is at stake. Even a very few years since, how few in this country were 
possessed of a sufficient share of that knowledge for such an 
application of it. Men who had risen to the highest rank in their 
profession, scarce knew a nettle from a crowfoot j and the capability of 
not confounding a mullein with a foxglove, seemed almost a miraculous 
stretch of botanical acquirement for a doctor, to one who had heard, in 
a very learned assembly too, a yellow gentian, in full flower, hailed as 
a splendid specimen of digitalis. Such ignorance, however, was 
pardonable in the accomplished who betrayed it—in one educated at a 
period in which the utility of botany was not even dreamed of, as 
a necessary part of the study for a physician. Now, however, who 
would be justified in pleading apology for overlooking or slighting the 
advantages it offers ? Surely no one is ignorant that the structure of 
the vegetable frame is determined by laws as absolute, as invariable in 
their action, when left to the guidance of nature, as are those which 
govern the development of the various species of animal existence; and 
as the mighty genius of comparative anatomy, the highly talented and 
lamented Cuvier, could, by his magic touch, bid the disunited and 
scattered bones of a thousand different individuals arrange in the 
original order of the frames they once gave form to and supported; so 
the botanist, practiced in the intricate lore of vegetable anatomy and 
