80 DARWINIANA. 



that more then a hundred years ago Mr. Dollond hav- 

 ing found out, after many experiments, that some kinds 

 of glass have the power of dispersing light, for each de- 

 gree of its refraction, much more than other kinds, and 

 that on the discovery of this fact he contrived to make 

 telescopes in which he passed the light through two 

 object-glasses successively, one of which he made of 

 crown and one of flint glass, so ground and adapted to 

 each other that the greater dispersion produced by the 

 substance of one should be corrected by the smaller dis- 

 persion of the other. This contrivance corrected entire- 

 ly the colored images which had rendered all previous 

 telescopes very imperfect. He finds in this invention 

 all the elements of design, as it appeared in the thought 

 and action of a human designer. First, conjecture of 

 certain laws or facts in optics. Then, experiment 

 proving these laws or facts. Then, the contrivance 

 and formation of an instrument by which those laws or 

 facts must produce a certain sought result. 



Thus enlightened, our skeptic turns to his crystal- 

 line lens to see if he can discover the work of a 

 Dollond in this. Here he finds that an eye, having a 

 crystalline lens placed between the humors, not only 

 refracts the light more than it would be refracted by 

 the humors alone, but that, in this combination of 

 humors and lens, the colors are as completely corrected 

 as in the combination of Dollond's telescope. Can it 

 be that there was no design, no designer, directing the 

 powers of life in the formation of this wonderful 

 organ % Our skeptic is aware that, in the arts of man, 

 great aid has been, sometimes, given by chance, that 

 is, by the artist or workman observing some fortuitous 



