tice of physic and surgery, the process of embalming, the 

 catastrophes of the field of battle, the accidents of common 

 life, and the natural curiosity of man, as well as the con- 

 stant habit of examining the structure of the inferior 

 animals, had made men acquainted with the leading facts 

 of human Anatomy before the period of Aristotle, who 

 raised it to the dignity of a science ; and all his successors 

 have endeavoured to extend its bounds. The great body 

 of knowledge respecting his internal economy, accumu- 

 lated from the experience of so many ages, now forms 

 the subject of many separate branches of science, the 

 details of which are conducted with great learning and 

 ability by my distinguished Colleagues in this Institution. 

 The structure and functions of the human body are there- 

 fore objects of attention in this place only as the standards 

 of comparison, from which we trace the modifications of 

 form throughout all the lower classes of the Animal King- 

 dom. We compare the organs of the inferior animals 

 with the similar organs of man, to determine the extent 

 of their deviation, and by watching the result of this 

 change of structure, important light is thrown on the func- 

 tions of the various parts. In animals far distant in the 

 zoological scale, where similar organs no longer exist, we 

 discover analogies of use between parts totally dissimilar 

 in structure, which point out their uses in the economy, 

 and mutually illustrate their functions. From the com- 

 parisons thus constantly instituted in all zootomical en^ 

 quiries, this science has been denominated Comparative 

 Anatomy. 



Comparative Physiology treats of the functions of the 

 lower animals. It considers the organs in a state of action, 

 and determines the purposes they are destined to serve in 

 the living economy. It makes us acquainted with the 

 uses of all the parts of the inferior animals, and investi- 

 gates the physical causes of all the vital phenomena they 

 exhibit. It enquires into the means by which the various 

 motions of animals are effected, whether of the whole body 

 from place to place, or of voluntary or involuntary parts. 



