PART III. 



THE SENSORIAL FUNCTIONS. 



Chapter I. 



SENSATION. 



The system of mechanical and chemical functions 

 which we have been occupied in reviewing, has 

 been established only as a foundation for the en- 

 dowment of those higher faculties w^iich constitute 

 the great objects of animal existence. It is in the 

 study of these final purposes that the scheme of 

 nature, in the formation of the animal world, opens 

 and displays itself in all its grandeur. The whole 

 of the phenomena we have hitherto considered 

 concur in one essential object, the maintenance of 

 a simply vital existence. Endowed with these pro- 

 perties alone, the organized system would possess 

 all that is absolutely necessary for the continuance 

 and support of mere vegetative life. The machinery 

 provided for this purpose is perfect and complete 

 in all its parts. To raise it to this perfection, not 

 only has the Divine Architect employed all the 

 properties and powers of matter which science has 

 yet revealed to man, but has also brought into 

 play the higher and more mysterious energies of 

 nature, and has made them to concur in the great 



