36 APPLICATION OF THE 



proportion ; and perhaps, have never been submitted to a 

 trial and examination, sufficiently accurate, long enough 

 continued, or often enough repeated. No accounts, which 

 I have seen, are satisfactory. The mutilated animal may 

 live and grow fat, as was the case of the dog deprived of 

 its spleen, yet may be defective in some other of its func- 

 tions ; which, whether they can all, or in what degree of 

 vigour and perfection, be performed, or how long preserv- 

 ed, without the extirpated organ, does not seem to be as- 

 certained by experiment. But to this case, even were it fully 

 made out, may be applied the consideration which we sug- 

 gested concernmg the watch, viz. that these superfluous 

 parts do not negative the reasoning which v/e instituted 

 concerning those parts which are useful, and of which we 

 know the use. The indication of contrivance, with re- 

 spect to them, remains as it was before. 



III. One atheistic way of replynig to our observations 

 upon the works of nature, and to the proofs of a Deity 

 which we thnik that we perceive in them, is to tell us, that 

 all which we see must necessarily have had some form, and 

 that it might as well be its present torm, as any other. Let 

 us now ap;)ly 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, bono, membrane, cartilage, &c. ; but that it should 

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

 prehends, viz. that it should have consisted, first, of a se- 

 ries of transparent lenses (very different, by the by, even 

 in their substance, from 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 receive the image, formed 

 by pencils of light, transmitted 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 pur- 

 poses of sensation. That this fortunate conformation of 

 parts should have been the lot, not of one individual out 



