tures. It may be claimed that these modes 

 of reasoning give Michell a place as the 

 early pioneer in the great modern problem 

 of the configuration and structure of the 

 universe, which first rose to prominence 

 twenty years afterwards, by the labours 

 of Sir William Herschel, founded on 

 similar views. 



"In regard, to optics, Michell was a 

 thoroughgoing Newtonian, as was natural 

 in his time. Light for him consisted of 

 corpuscles projected from the luminous 

 body, rather than waves propagated 

 through an aether. He even thought 

 that, like everything material, they must 

 be subject to gravitation ; and he de- 

 veloped a speculation that the velocities 

 of the corpuscles shot out from one of the 

 larger stars must be sensibly diminished 

 by the backward pull of its attraction, 

 and thus be more deviated by a glass prism, 

 a supposition which he proposed to test. 

 At the end of his Memoir of 1767 (p. 261) 

 he even suggests that the c twinkling of 



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