66 NATURAL THEOLOGY. 



its present form as any other. Let us now apply 

 this answer to the eye, as we did before to the 

 watch. Something or other must have occupied 

 that place in the animal's head ; must have filled 

 up, we will say, that socket : we will say, also, 

 that it must have been of that sort of substance 

 which we call animal substance, as flesh, bone, 

 membrane, or cartilage, &:c. But that it should 

 have been an eye, knowing as we do what an eye 

 comprehends, — viz. that it should have consisted, 

 first, of a series of transparent lenses (very differ- 

 ent, by-the-by, even in their substance, from the 

 opaque materials of which the rest of the body is, 

 in general at least, composed ; and with which the 

 whole of its surface, this single portion of it ex- 

 cepted, is covered :) secondly, of a black cloth or 

 canvass (the only membrane of the body which is 

 black,) spread out behind these lenses, so as to re- 

 ceive the image formed by pencils of light trans- 

 mitted through them ; and placed at the precise 

 geometrical distance, at which, and at which alone, 

 a distinct image could be formed, namely, at the 

 concourse of the refracted rays: thirdly, of a large 

 nerve communicating between this membrane and 

 the brain ; without which, the action of light upon 

 the membrane, however modified by the organ, 

 would be lost to the purposes of sensation : — that 

 this fortunate conformation of parts should have 

 been the lot, not of one individual out of many 

 thousand individuals, like the great prize in a lot- 

 tery, or like some singularity in nature, but the 



