56 Mechanical Philosophi/. 



made by the opinions and arts of this celebrated 

 empiric, and his coadjutors, in Germany, in France, 

 and indeed, though in a less degree, throughout 

 every other part of Europe, is well known to all 

 acquainted with the literary history of that period; 

 as well as the detection, the decline, and the final 

 disgrace of them, and their principles/ 



MOTION, AND MOVING FORCES, 



This part of science also, within the century 

 under consideration, has received no small im-. 

 provement. The laws of r/zo^/o/z, as laid down by 

 Sir Isaac Newton, though found, by succeeding 

 philosophers, to be in general correct, were yet 

 by no means perfectly so. His principles of 

 motion in resisting mediums, particularly failed, 

 when brought to the test of accurate experiment. 

 Numerous have been the attempts to supply the 

 defects, and to correct the errors of these princi-. 

 pies: among which the labours of D. Ber- 

 noulli, and of M. D'Alembert, deserve to be 

 considered as by far the most distinguished and 

 successful. The latter in particular, in the course 

 of his investigations, discovered a general rule, 

 adequate to the determination of many important 

 questions in the science of motion, and applying to 

 the most compound and perplexing cases/ 



The inaccuracy of Newton's principles, with 

 regard to projectiles, was first ascertained and an- 

 nounced by M. Ressons, a French artillerist, in 

 1716. Nothing material, hov/ever, was done to- 

 ward the establishment of new and more just laws, 

 till 1742, when Benjamin Robins, of Great-Bri- 

 tain, published his Neio Principles of Gunnery, a 



y For an amusing account of the noise and pretensions made by Mess-; 

 MER, se^ Willtch's Lectures on Diet and Regimen, &c. p. lo6, &c. 

 JJe-w-York edition. 



s CQN50RCET on the Mind, p. %TS^ 



