DEA 



DEA 



compression of the auditory nerve ; or 

 from some collection of matter in the ca- 

 vities of the inner ear ; or from the audi- 

 tory passage being stopped up by some 

 hardened excrement ; or, lastly, from 

 some excrescence, a swelling of the 

 glands, or some foreign body introduced 

 within it. Those born deaf are also 

 dumb, as not being able to learn any lan- 

 guage, at least in the common way. How- 

 ever, as the eyes in some measure serve 

 them for ears, they may understand what 

 is said by the motion of the lips, tongue, 

 &c. of the speaker ; and even accustom 

 themselves to move their own, as they see 

 other people do, and by this means learn 

 to speak. Thus it was that Dr. Wallis 

 taught two young gentlemen, born deaf, 

 to know what was said to them, and to 

 return pertinent answers. Digby gives us 

 another instance of the same, within his 

 own knowledge ; and there was a Swiss 

 physician lately living in Amsterdam, one 

 John Conrad Amman, who effected the 

 same in several children born deaf with 

 surprising success. 



In the " Phil. Trans." No. 312, we 

 have an account by Mr. Waller, It. S. Se- 

 cretary, of a man and his sister, each 

 about 50 years old, born in the same town 

 with Mr. Waller, who had neither of 

 them the least sense of hearing ; yet both 

 of them knew, by the motion of the lips 

 only, whatever was said to them, and 

 would answer pertinently to the question 

 proposed. It seems they could both hear 

 and speak when children, but lost their 

 sense afterwards ; whence they retained 

 their speech, which, though uncouth, was 

 yet intelligible. Such another instance is 

 related by Bishop Burnet of a young wo- 

 man. " At two years old, they perceiv- 

 ed she had lost her hearing ; and ever 

 since, though she hears great noises, yet 

 hears nothing of what is said to her : but 

 by observing the motion* of the mouth 

 and lips of others, she acquired so many 

 words, that out of these she has formed 

 a sort of jargon, in which site can hold 

 conversation whole days with those that 

 can speak her language. She knows no- 

 thing that is said to her, unless she see 

 the motion of their mouths thai speak to 

 her, so that in the night they are obliged 

 to light candles to speak to her. One 

 thing will appear the strangest part of the 

 whole narration : she has a sister, with 

 whom she has practised her language 

 more than with any body else ; and in 

 the night, by laying her hand on her sis- 

 ter's mouth, she can perceive by that 



what she says, and so can discourse with 

 her in the dark. 



It is observable, that deaf persons, and 

 several others thick of hearing, hear bet- 

 ter, and more easily, if a loud noise be 

 raised at the time when you speak to 

 them j which is owing, no doubt, to the 

 greater tension of the ear-drum on that 

 occasion. Dr. Wallis mentions a deaf 

 woman, who, if a drum were beat in the 

 room, could hear any thing very clearly ; 

 so that her husband hired a drummer for 

 a servant, that by this means he might hold 

 conversation with his wife. The same 

 author mentions another, who, living near 

 a steeple, could always hear very well if 

 there was a ringing of three or four bells, 

 but never else. See DL T MBSESS. 



DEAL, a thin kind of fir planks, of 

 great use in carpentry : they are formed 

 by sawing the trunk of a tree into a great 

 many longitudinal divisions, of more or 

 less thickness, according to the purposes 

 they are intended to serve. Deals are 

 rendered much harder by throwing them 

 into salt water as soon as they are sawed, 

 keeping them there three or four days, 

 and afterwards drying them in the air or 

 sun ; but neither this, nor any other me- 

 thod, yet known, will preserve them from 

 shrinking. Deals are imported into this 

 country from Christiana, and other parts 

 of Norway ; from D.mtzic, and various 

 parts of Prussia; from St. Petersburg, 

 Archangel, Narva, Memel, &c. They 

 are sold by the piece, or by the stand.ml 

 hundred, or by the long hundred of 120. 

 A standard, or reduced deal, is one inch 

 and a half thick, eleven inches wide, and 

 twelve feet long. 



DEAN, an ecclesiastical dignitary in 

 cathedral and collegiate churches, and 

 head of the chapter. As there are two 

 foundations of cathedral churches in Eng- 

 land, the old and the new, so there are 

 two ways of creating deans. Those of the 

 old foundation, founded before the sup- 

 pression of monasteries, as the deans of 

 St. Paul's, York, &.c. are raised to that 

 dignity much after the manner of bishops, 

 the king first sending his conge 1 d'elire, 

 the chapter electing, and the king grant- 

 ing his royal assent, the bishop confirms 

 him, and gives his mandate to install him. 

 Those of the new foundation, whose 

 deaneries were raised upon the ruins 

 of priories and convents, such as the 

 deans of Canterbury, Durham, Ely, Nor- 

 wich, Winchester, &c. are donative, and 

 installed by virtue of the king's letters 

 patent, without either election or confir- 

 mation. Canonists distinguish between 



