sict. it.] DISSERTATION SECOND. 67 



the match and the expulsion of the ball, constitutes a latent 

 process of a very remarkable and complicated nature, 

 which, however, we can now trace with some degree of 

 accuracy. In mechanical operations, we can often follow 

 this process still more completely. When motion is com- 

 municated from any body to another, it is distributed 

 through all the parts of that other, by a law quite beyond 

 the reach of sense to perceive directly, but yet subject to 

 investigation, and determined by a principle, which, though 

 late of being discovered, is now generally recognised. — 

 The applications of this mechanical principle are perhaps 

 the instances in which a latent, and, indeed, a very recon- 

 dite process, has been most completely analyzed. 



The latent schematism is that invisible structure of bo- 

 dies, on which so many of their properties depend. When 

 we inquire into the constitution of crystals, or into the in- 

 ternal structure of plants, &c. we are examining into the 

 latent schematism. We do the same when we attempt to 

 explain elasticity, magnetism, gravitation, &c. by any pe- 

 culiar structure of bodies, or any arrangement of the par- 

 ticles of matter. ' 



In order to inquire into iheform or cause of any thing 

 by induction, having brought together the facts, we are to 

 begin with considering what things are thereby excluded 

 from the number of possible forms. This exclusion is the 

 first part of the process of induction : it confines the field 

 of hypothesis, and brings the true explanation within nar- 

 rower limits. Thus, if we were inquiring into the quality 

 which is the cause of transparency in bodies ; from the 

 fact that the diamond is transparent, we immediately ex- 

 clude rarity or porosity as well as fluidity from those caus- 

 es, the diamond being a very solid and dense body. 



' Nov. Org. lab. ii. Aph. 5, 6, &e. 



