CENTURY III. 133 



eye when you would see sharply ; and erect your 

 ear when you would hear attentively ; which in 

 beasts that have ears moveable is most manifest. 



267. The beams of light, when they are multi 

 plied and conglomerate, generate heat, which is a 

 different action from the action of sight : and the 

 multiplication and conglomeration of sounds doth 

 generate an extreme rarefaction of the air ; which 

 is an action materiate, differing from the action of 

 sound ; if it be true, which is anciently reported, that 

 birds with great shouts have fallen down. 



Dissents of visibles and audibles. 



268. The species of visibles seem to be emissions 

 of beams from the objects seen, almost like odours, 

 save that they are more incorporeal : but the species 

 of audibles seem to participate more with local motion, 

 like percussions, or impressions made upon the air. 

 So that whereas all bodies do seem to work in two 

 manners, either by the communication of their 

 natures, or by the impressions and signatures of their 

 motions ; the diffusion of species visible seemeth to 

 participate more of the former operation, and the 

 species audible of the latter. 



269. The species of audibles seem to be carried 

 more manifestly through the air than the species of 

 visibles : for I conceive that a contrary strong wind 

 will not much hinder the sight of visibles, as it will 

 do the hearing of sounds. 



270. There is one difference above all other? 

 between visibles and audibles, that is the most re 



