94 On tin ZtruBure and Ufa of the Memhrana Timpani. 



This difcovery in the elephant having kd to that of a fimilar con(lru£llon in the human 

 membrana tympani, it may not be improper to relate the circumftances by which I became 

 engaged in the inveftigation of the organ of hearing in that animal. 



Three different opportunities have occurred of difietting the elephant in London, by the 

 deaths of thofe which had been prefented to his Majefty, and were kepc at the King's ftables 

 at Pimlico. One of them was given to the late Dr. Hunter; one to his brother Mr. J. 

 Hunter; and the third to Sir Aditon Lever. 



From my being connefted with Mr. John Hunter's purfuits in comparative anato.my, I 

 was employed throughout the whole of thefe difledlions, and became extremely defirous of 

 examining the internal parts of the ear, the ftrufture of that organ in the human body 

 having at a very early period particularly engaged my attention ;* but neither Dr. Hunter 

 nor his brother could be prevailed upon to facrifice fo large a portion of the fkuli as was' 

 neceflary for the purpofe. 



When Mr. Corfe arrived from Bengal, lad year, and mentioned his having brought over 

 a number of flculls of elephants, in order to fliow the progrefs of the formation of their 

 grinding teeth, f the defire to examine the organ of hearing in that animal recurred to me 

 fo ftrongly, that I requefted to have one of the flculls for that purpofe, and Mr. Corfe 

 very readily and obligingly complied with my requeft. 



After having examined the organ in the dried fkuU, the want of the membrana tympani, 

 and of the fmall bones, made the information thus received of a very imfatisfaftory nature, 

 and increafed the defire of feeing thefe parts in the recent head. In confidering how this 

 could be done, I recollefled a mutilated elephant's head, preferved in fpirits, which had 

 been fent to Mr. Hunter, but, from the multiplicity of his engagements, had remained 

 negle£lcd in the caflt at the time of his death, and in the following year was dried, to 

 ihow the probofcis, that it might not be altogether fpoiled. 



Upon examining this dried head, the bones had been fo much broken, that one of the 

 organs of hearing was altogether wanting : the other, however, was fortunately entire ; 

 and the membrana tympani and fmall bones, having been little difturbed in the drying of 

 the parts, remained nearly in their natural fituation. 



* In the year 1776, I injeiled the cochlea and femicircular canals of the human ear with a coinpofition of 

 wax and rofrn. 'This w.is done by placing the temporal bone in the receiver of an air pump, the upper part 

 of which was in the form of a funnel, rendered air-tight by a cork being fitted into its neck, and furrounded 

 with bees' wax. After the air had been exliaufted, the hot injeftion, poured into the funnel, melted the 

 wax and the cork was pulled out by means of a ftring previoufly attached to it ; the injeftion immediately 

 rulhed into the receiver, !ind was forced, by the preffure of the atmofphere, into the cavities of the tem- 

 poral bone. 



f On this fubjeft, a very ingenious paper has been fnice publiflied by him, in the Philofophical 

 Tranfaflions for the year 1799. 



Th« 



