242 OF SOUND AXD HEARING. 



greatly to hinder sight, provided only the positions of the 

 parts of the body be after a simple order and with straight 

 passages, as in glass, water, crystal, diamond ; but a little 

 silk or linen cloth breaks the sight, though they be bodies 

 very thin and porous; but cloths of this kind little or 

 nothing hinder hearing, which those solids do exceedingly. 

 Hence it happens, that unto the reverberation of visibles a 

 small mirror suffices, or like transpicuous body, let it be 

 only placed in a right line, where the visibles pass ; but 

 unto making of the reverberation of echo, it needeth also 

 to confine the sound from the side, because it is carried to 

 all sides. The visible object is further carried, in propor 

 tion, than sound. 



Visibles, too nearly approached to the eye, are not so 

 well seen as at some little distance, so as the beams may 

 meet in a more acute angle ; but in hearing, the nearer the 

 better. But herein there may be twofold error. The first, 

 because to seeing there is required light; but if the object 

 be brought very near to the eye, this is shut out. For I 

 have heard of one trustworthy, which was cured of cata 

 racts of the eyes, when the little silver needle moved over 

 the very pupil of his eye, and did touch it, he without any 

 medium (that silver needle being far narrower than the 

 pupil itself of the eye) saw perfectly the needle. The 

 second, that the cave of the ear is distinctly interposed 

 before the organ of hearing, so as being without, the sound 

 is altogether unable to touch the bone and membrane of 

 hearing. 



The species of sight are more swiftly conveyed than 

 sounds, as appeareth in the flash and report of guns ; also 

 in lightning and thunder, where the thunder is heard after 

 a while. 



I conceive also that the species of sound do hang longer 

 in the air than visibles. For although neither do these 

 perish on the instant, as we see in a ring spinning, and 

 lute-strings fillipped, and in twilight and the like; yet I 

 deem that sounds, for that they are carried by the wind, 

 stay longer. 



The beams of light being gathered, induce heat also, 

 which is an action diverse from the visible quality. In 

 like manner, if it be true that shouts have cast down birds 

 flying over, that is also an action exceedingly diverse from 

 the audible quality. 



There seemeth not in visibles to be found an object as 

 odious, and noisome to the sense, as in audibles ; but they 



