OF SOUND AND HEARING. 247 



were wet, another if dry. I conceive, likewise, in virginals, 

 or the viol, if the board upon which the strings are strained 

 were of brass, or of silver, it should yield a somewhat 

 different sound. But of all these things let there be better 

 inquiry. 



Further, in respect of the communication, it would be 

 inquired, what the diversity and inequality of bodies may 

 do ; as if three bells should be made to hang, the one 

 within the other, with some space of air interposed, and the 

 outer bell were chimed upon with an hammer, what sound 

 it should give, in respect of a single bell. 



Let a bell be covered on the outside with cloth or silk, 

 and let it be noted, when the bell is struck by the tongue 

 within, what that covering shall do to the sound. 



If there were in a viol a plate of brass, or of silver, 

 pierced with holes, in place of that of wood, it would be 

 seen what this shall do to the sound. 



There are used in Denmark, and are even brought hither, 

 drums of brass, not of wood, less than those of wood, and 

 they give, I think, a louder sound. 



The agitation of the air by great winds shall not, I 

 think, yield much sound, if woods, waves, buildings, or the 

 like be away ; yet is it received that, before tempests, there 

 be some murmurings made, in woods, albeit to the sense 

 the blast be not yet perceived, nor do the leaves stir, (a) 



() Three chapters are deficient, which there wanted leisure to completing. 



