480 SIMSON. 



its foundations is wholly untrue. Not only did he always 

 explain its principles to his pupils, though in a manner 

 peculiar to himself, but he has left behind him a trea- 

 tise demonstrating the fundamental laws of the cal- 

 culus, and we now possess it in a printed form. Equally 

 groundless is the notion that he questioned the sound- 

 ness of the Newtonian Philosophy. He was not ena- 

 bled to make Sir Isaac's acquaintance during his resi- 

 dence in London ; but among those he lived with he 

 constantly had seen him viewed with a peculiar ob- 

 servance, and Halley in particular regarded him as 

 hardly human, and his attainments in science as exalt- 

 ing our species, while they ennobled himself, its rarest 

 individual. Simson's copy of the ' Principia ' is fully 

 noted in the margin with illustrations, showing that 

 he entirely assented to the results of the investigations 

 in the several propositions, and only wished to substi- 

 tute certain steps in the demonstrations. Professor 

 Robison has also related (Art. Simson, Encyc. Brit. 

 xvii. 505) his constant remark, that the celebrated 

 proposition in the ' Principia ' on inverse centripetal 

 forces " was the most important ever delivered to man- 

 kind in the mixed mathematics." 



While he remained in London the expected vacancy 

 occurred in the chair at Glasgow, and he returned 

 thither. The professors appear to have thought it 

 right that their former neglect of duty should be com- 

 pensated by a very superfluous show of more than need- 

 ful attention to it on this occasion ; for they required 

 Mr. Simson to give proof of his fitness to succeed the 

 sinecure incumbent, by solving a geometrical problem, 

 of which it is all but absolutely certain that they could 



