140 HISTORY OF PHYSICAL ASTRONOMY. 



tions of the stars as a mechanical problem, subject 

 to the same conditions as other mechanical pro- 

 blems, and capable of the same exactness of solu- 

 tion. And there was an especial inconsistency in 

 the circumstance of the Theory of Vortices being 

 put forwards by Descartes, who pretended, or was 

 asserted by his admirers, to have been one of the 

 discoverers of the true laws of motion. It cer- 

 tainly shows both great conceit and great shallow- 

 ness, that he should have proclaimed with much 

 pomp this crude invention of the ante-mechanical 

 period, at the time when the best mathematicians 

 of Europe, as Borelli in Italy, Hooke and Wallis 

 in England, Huyghens in Holland, were patiently 

 labouring to bring the mechanical problem of the 

 universe into its most distinct form, in order that 

 it might be solved at last and for ever. 



I do not mean to assert that Descartes bor- 

 rowed his doctrines from Kepler, or from any of 

 his predecessors; for the theory was sufficiently 

 obvious ; and especially if we suppose the inventor 

 to seek his suggestions rather in the casual ex- 

 amples offered to the sense than in the exact laws 

 of motion. Nor would it be reasonable to rob this 

 philosopher of that credit, of the plausible deduc- 

 tion of a vast system from apparently simple prin- 

 ciples, which, at the time, was so much admired ; 

 and which undoubtedly was the great cause of the 

 many converts to his views. At the same time we 

 may venture to say that a system of doctrine thus 



