84- NATURAL HISTORY. 



parchment or trunk, and the ear to the other, the 

 sound is heard much farther than in the open air.* 

 The cause is, for that the sound spendeth, and is 

 dissipated in the open air ; but in such concaves it 

 is conserved and contracted. So also in a piece of 

 ordnance, if you speak in the touch-hole, and another 

 lay his ear to the mouth of the piece, the sound 

 passeth and is far better heard than in the open air. 



130. It is further to be considered, how it 

 proveth and worketh when the sound is not inclosed 

 all the length of its way, but passeth partly through 

 open air ; as where you speak some distance from a 

 trunk ; or where the ear is some distance from the 

 trunk at the other end ; or where both mouth and 

 ear are distant from the trunk. And it is tried, that 

 in a long trunk of some eight or ten foot, the sound 

 is holpen, though both the mouth and the ear be a 

 handful or more from the ends of the trunk ; and 

 somewhat more holpen, when the ear of the hearer 

 is near, than when the mouth of the speaker. And 

 it is certain, that the voice is better heard in a cham 

 ber from abroad, than abroad from within the 

 chamber. 



131. As the inclosure that is round about and in- 

 tire, preserveth the sound ; so doth a semi-concave, 

 though in a less degree. And therefore, if you 

 divide a trunk, or a cane into two, and one speak at 

 the one end, and you lay your ear at the other, it 

 -will carry the voice farther, than in the air at large. 

 Nay further, if it be not a full semi-concave, but if 

 you do the like upon the mast of a ship, or a long 



