FINAL CAUSES. 37 



lens at the proper distance in a darkened box, for the pur- 

 pose of obtaining vivid pictures of the external scene, evince 

 his knowledge of the laws of light, of the properties of re- 

 fracting media, and of the refined combinations of those me- 

 dia by which each pencil is brought to a separate focus, and 

 adjusted to form an image of remote objects ? Does it not, 

 in like manner, argue the most profound knowledge and 

 foresight in the divine Artist, who has so admirably hung 

 the crystalline lens of the eye in the axis of a spherical 

 case, in the forepart of which He has made a circular win- 

 dow for the light to enter, and spread out on the opposite 

 side a canvas to receive the picture ? Has no thought been 

 exercised in darkening the walls of this camera obscura, and 

 thus preventing all reflection of the scattered rays, that 

 might interfere with the distinctness of the image ? 



But we farther observe in the eye many exquisite refine- 

 ments of construction, by which various defects, unavoida- 

 ble in all optical instruments of human workmanship, are 

 remedied. Of this nature are those which render the orjian 

 achromatic, which correct the spherical aberration, and which 

 provide for the adjustment of its refracting powers to the 

 different distances of the objects viewed; not to speak of all 

 the external apparatus for the protection, the preservation, 

 and the movements of the e3^e-ball. and for contributing in 

 every way to the proper performance of its office. Are not 

 all these irrefragable proofs of the continuity of the same 

 design; and are they not calculated still farther to exalt our 

 ideas of the Divine Intelligence, of the elaborate perfection 

 impressed upon His works; and of the comprehensive views 

 of His providence ? 



These facts, if they stood alone, would be sufficient to 

 lead us irresistibly to this conclusion: but evidence of a si- 

 milar kind may be collected in abundance from every part 

 of living nature to which our attention can be directed, or 

 to which our observations have extended. The truths they 

 teach not only acquire confirmation by the corroborating 

 tendency of each additional fact of the same description, but 

 the multitude of these facts is so great, that the general con- 



