ANIMALS. 43 



they form an unjust idea. In this manner, as 

 those people hear false, they also, without know- 

 ing it, sing false. Those persons also frequently 

 deceive themselves with regard to the side from 

 whence the sound comes, generally supposing the 

 noise to come on the part of the best ear. 



Such as are hard of hearing find the same ad- 

 vantage in the trumpet made for this purpose 

 that short-sighted persons do from glasses. These 

 trumpets might be easily improved so as to in- 

 crease sounds, in the same manner that the tele- 

 scope does objects : however, they could be used 

 to advantage only in a place of solitude and still- 

 ness, as 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 animals. With these, it is only a 

 warning against danger, or an encouragement to 

 mutual assistance. In man, it is the source of 

 most of his pleasures ; 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 

 only by sensual objects. We have an instance 

 of a young man who, being born deaf, was restor- 

 ed, at the age of twenty-four, to perfect hearing : 

 the account is given in the Memoirs of the Aca- 

 demy of Sciences, 1703, page 18. 



A young man of the town of Chartrqs, between 

 the age of twenty-three and twenty-four, the son 

 of a tradesman, and deaf and dumb from his birth, 

 began to speak all of a sudden, to the great asto- 



