416 Recapitulation. 



comparatively small. In the seventeenth, his plan 

 of philosophizing was more frequently adopted. 

 But in the eighteenth, it obtained an ascendency 

 and prevalence never before known in the history 

 of science. Never were there so many heads and 

 hands at work, to deveiope the arcana of na- 

 ture, to investigate her laws, and to bring former 

 principles, as far as possible, to the test of weight, 

 measurement, and vision. The amount of experi- 

 ments of different kinds, and instituted for differ- 

 ent purposes, laid before the public, within this 

 period, by individuals, and by learned societies,, 

 forms a mass of stupendous extent, and presents 

 one of the most prominent features of the age. 



These remarks apply almost exclusively to the 

 physical sciences ; for there is too much reason to 

 suppose, as will be afterwards shown, that, in the 

 philosophy of the human mind, and especially of 

 human duty, the prevailing character of the age 3 

 and particularly of the latter part of it, has been 

 that of vain speculation and fantastic theory, rather 

 than of principles dictated by sober and enlight- 

 ened experience. But in the physical sciences, 

 amidst much false theory, such an immense variety 

 and amount of facts and experiments have been 

 laid before the public, as eminently to distinguish 

 the eighteenth from all preceding centuries. 



5. The last age was remarkably distinguished 

 by revolutions in science. Theorists were more 

 numerous than in any former period, their systems 

 more diversified, and revolutions followed each 

 other in more rapid succession. In almost every 

 department of science, changes of fashion, of doc- 

 tririe, and of authority, have trodden so closely on 

 the heels of each other, that merely to remember 

 and enumerate them would be an arduous task. 



The frequency and rapidity of scientific revo- 

 lutions may be accounted for in various ways. 

 The extraordinary diffusion of knowledge -, thp 



