8 HISTORY OF MECHANICS. 



made to extend the statical doctrine of Archimedes, 

 failed, in such a manner as to show that his fol- 

 lowers had not clearly apprehended the idea on 

 which his reasoning altogether depended. The 

 clouds which he had, for a moment, cloven in his 

 advance, closed after him, and the former dimness 

 and confusion settled again on the land. 



This dimness and confusion, with respect to all 

 subjects of mechanical reasoning, prevailed still, at 

 the period we now have to consider; namely, the 

 period of the first promulgation of the Copernican 

 opinions. This is so important a point that I must 

 illustrate it further. 



Certain general notions of the connexion of 

 cause and effect in motion, exist in the human 

 mind at all periods of its developement, and are 

 implied in the formation of language and in the 

 most familiar employments of men's thoughts. But 

 these do not constitute a science of Mechanics, any 

 more than the notions of square and round make 

 a Geometry, or the notions of months and years 

 make an Astronomy. The unfolding these Notions 

 into distinct Ideas, on which can be founded prin- 

 ciples and reasonings, is further requisite, in order 

 to produce a science ; and, with respect to the doc- 

 trines of Motion, this was long in coming to pass ; 

 men's thoughts remained long entangled in their 

 primitive and unscientific confusion. 



We may mention one or two features of this 

 confusion, such as we find in authors belonging to 

 the period now under review. 



