446 THE SENSORIAL FUNCTIONS. 



we are permitted to behold, have the characters 

 of intention been more deeply and legibly en- 

 graved than in the organ of vision, where the 

 relation of every part to the effect intended to 

 be produced is too evident to be mistaken, and 

 the mode in which they operate is at once 

 placed within the range of onr comprehension. 

 Of all the animal structures, this is, perhaps, the 

 one which most admits of being brought into 

 close comparison with the works of human art ; 

 for the eye is, in truth, a refined optical instru- 

 ment, the perfection of which can never be fully 

 appreciated until we have instituted such a com- 

 parison ; and the most profound scientific inves- 

 tigations of the anatomy and physiology of the 

 eye concur in showing that the whole of its 

 structure is most accurately and skilfully adapted 

 to the physical laws of light, and that all its parts 

 are finished with that mathematical exactness 

 which the precision of the effect requires, and 

 which no human effort can ever hojDe to ap- 

 proach, — far less to attain. 



To the prosecution of this inquiry we are 

 further invited by the consciousness of the incal- 

 culable advantages we derive from the sense of 

 sight, the choicest and most enchanting of our 

 corporeal endowments. The value of this sense 

 must, indeed, appear inestimable, when we con- 

 sider of how large a portion of our sensitive 

 and intellectual existence it is the intermediate 



