Introductory Lecture. 
295 
of our ardent countrymen, whose enthusiastic convictions 
and impassioned eloquence have worked their usual effects 
among the young devotees of medicine. Attention has thus 
been diverted, in some measure, from the Materia Medica, 
and the effect has been greater, as the tendency of the doc- 
trines inculcated is to produce an impression, that compara- 
tively few remedial agents are necessary in the treatment of 
disease. 
No error is greater than that which would limit the Materia 
Medica within a very narrow compass. It is true that the 
general indications for the use of medicines are not nume- 
rous, and may therefore be answered by a few remedies. 
But there are countless varieties in the circumstances of dis- 
ease, dependent on the degree, peculiar nature, and complica- 
tions of the morbid action, and on the habits, tastes, and dis- 
positions of the patient, which modify the main indication, 
and consequently require some modification in the character 
of the remedy proposed. To meet these diversified calls of 
disease, nature has provided an equal diversity of means; and 
he who neglects to avail himself of the advantages thus af- 
forded him, is guilty of injustice alike to his patient and him- 
self. Let us suppose, for example, that, in a number of cases 
presenting different aspects, there may exist a coincident in- 
dication for the use of a cathartic. It is not allowable for the 
physician to meet this indication, in every instance, by the 
use of the same medicine. On the contrary, it is his duty to 
observe the peculiarities of each case, and endeavour to select 
the particular cathartic applicable to these peculiarities. Thus, 
if the symptoms requiring the use of purgative medicine be 
complicated with acidity of stomach, he will employ magnesia ; 
if with hepatic derangement, calomel ; if with general debility, 
rhubarb ; if with febrile excitement, one of the neutral salts ; 
and so on through a long catalogue of cathartics. The same 
remark is applicable to other classes of the Materia Medica ; 
and it will be at once perceived, that, upon these grounds, 
the number of medicines at the command of the physician can 
