1802-3. JET. 29-30.] PROFESSOR YOUNG. 245 



parts was originally suggested by the periodical succession 

 in which the appointed hours recur, but it appears to be 

 more convenient than any other for the regular classification 

 of the subjects. The general doctrines of motion and their 

 application to all purposes, variable at pleasure, supply the 

 materials of the first two parts, of which the one treats of 

 the motions of solid bodies and the other of those of fluids, 

 including the theory of light. The third part relates to the 

 particular history of the phenomena of nature, and of the 

 affections of bodies actually existing in the universe in- 

 dependently of the art of man, comprehending astronomy, 

 geography, and the doctrine of the properties of matter, 

 and of the most general and powerful agents that influence 

 it. 



The synthetical order of proceeding from simple and 

 general principles to their more intimate combinations in 

 particular cases, is by far the most compendious for con- 

 veying information with regard to sciences that are at all 

 referable to certain fundamental laws. For these laws being 

 once established, each fact, as soon as it is known, assumes its 

 place in the system, and is retained in the memory by its 

 relation to the rest as a connecting link. In the analytical 

 mode, on the contrary, which is absolutely necessary for 

 the first investigation of truth, we are obliged to begin by 

 collecting a number of insulated circumstances, which lead 

 us back by degrees to the knowledge of original principles, 

 but which, until we arrive at these principles, are merely a 

 burden to the memory. For the phenomena of nature 

 resemble the scattered leaves of the Sibylline prophecies ; 

 a word only, or a single syllable, is written on each leaf, 

 which, when separately considered, conveys no instruction 

 to the mind, but when, by the labour of patient investigation, 

 every fragment is replaced in its appropriate connexion, the 

 whole begins at once to speak a perspicuous and a har- 

 monious language. 



