364 HISTORY OF 



One of the most common disorders in old age is deafness ; 

 which probably proceeds from the rigidity of the nerves in the 

 labyrinth of the ear. This disorder, also, sometimes proceeds 

 from a stoppage of the wax, which art may easily remedy. In 

 order to know whether the defect be an internal, or an external 

 one, let the deaf person put a repeating watch into his mouth, 

 and if he hears it strike, he may be assured that bis disorder 

 proceeds from an external cause, and is, in some measure, ciu"- 

 able : " for there is a passage from the ears into the mouth, by 

 what anatomists call the eustachian tube ; and, by this passage, 

 people often hear sounds, when they are utterly without hear- 

 ing through the larger channel : and this also is the reason that 

 we often see persons who listen with great attention, hearken 

 with their mouths open, in order to catch all the sound at every 

 aperture." 



It often happens, that persons hear differently with one ear 

 from the other ; and it is generally found that these have what 

 is called, by musicians, a had ear. Mr Buffon, who has made 

 many trials upon persons of this kind, always found that their 

 defect in judging properly of sounds proceeded from the ine- 

 quality of their ears ; and receiving by both, at the same time, 

 unequal sensations, they form an unjust idea. In this manner, 

 as those people hear false, they also, without knowing it, sing 

 false. Those persons also frequently deceive themselves with 

 regard to the side from whence the sound comes, generally sup- 

 posing the noise to come on the part of the best ear. 



Such as are hard of hearing, find the same advantage in the 

 trumpet made for this purpose, that short-sighted persons do 

 from glasses. These trumpets might be easily improved so as 

 to increase sounds, in the same manner that the telescope does 

 obj ects ; however, they could be used to advantage only in a 

 jilace of solitude and stillness, a« the neighbouring sounds would 

 mix with the more distant, and the whole would produce in the 

 ear nothing but tumult and confusion. 



Hearing is a much more necessary sense to man than to ani- 

 mals. With these it is only a warning against danger, or an 

 encouragement to mutual assistance. In man, it is the source 

 ot most of his pleasure ; and without which the rest of his senses 

 would be of little benefit. A man born deaf, must necessarily 

 be dumb : and his whole sphere of knowledge must be bounded 



