pected light upon the nature and treatment of many 

 diseases. Physiology hitherto has been handled almost 

 exclusively by the anatomists. These gentlemen have 

 acted with a zeal and industry that cannot be too much 

 admired. They have examined the anatomical structure 

 of every organ of the human body; ascertained the 

 changes to which it is liable from disease ; and compared 

 it with the analogous organs in all the inferior animals. 

 A great deal of important knowledge has been the result 

 of this active examination : yet, after the anatomists have 

 exhausted all their ingenuity, it must be admitted that 

 our knowledge both of the organs and functions is still 

 very imperfect. A new and more subtile species of 

 anatomy remains still to be applied. Where the labours 

 of the anatomist terminate, those of the chemist should 

 begin. This chemical investigation of the animal body 

 may be just said to be commencing at present : for it 

 was not till the atomic theory was brought to considerable 

 simplicity and perfection, that such an investigation was 

 possible. It is easy to see that it must contribute pro- 

 digiously to the advancement of physiological knowledge. 

 I have been long anxious to lay before my students the 

 general results already attained by these chemical investi- 

 gations. But the preliminary discussions into which I 

 was obliged to enter, left us too little time at the end of 

 the session, to enter upon them ; and after having been at 

 no little pains in collecting and arranging the different 

 facts from sources not easily accessible to students in 



