In commencing a course of lectures, it is usual to give 
some account of the origin and history, the objects and 
uses of the subject to be entered upon, by teacher and 
student. The practice has its advantages, in many respects, 
for all ought to be acquainted both with the object and the 
use of any study they are about to commence; but few can 
be interested about the history of a subject with which they 
are supposed to be totally unacquainted. Though a lec- 
turer may usually choose any part of his subject for his 
introductory discourse, there are occasions when he feels 
it expedient to give his own views on the subject to be 
studied. As I consider that to be my case, I shall enter 
at once into a consideration of the objects of Materia 
Medica and Therapeutics, and the sciences with which 
they are connected, and without which they cannot be 
understood ; adding a short survey of the history of the 
science, and concluding with some observations on the modes 
and means of teaching. 
Materia Medica treats of the nature in general of medi- 
cines, and Therapeutics of their application in the treatment 
of disease. * All substances which are applied to diseased 
organs, with a view to cure or relieve, and which possess this 
virtue, independent of their nutritive qualities, are medi- 
cines.' They are obtained from both the Organic and 
Inorganic kingdoms, i.e. from the Vegetable and Animal, as 
well as from the Mineral kingdom. It is necessary, therefore, 
B 
