3 66 Obj'rrvatkns on the Dejlnccthn 



bv difeafe, whilft others are left in their natural ftate ; stttm 

 hence, by the powers retained by fuch organ, after a partial' 

 destruction, we are enabled to judge of the functions per- 

 formed by thofe parts when the whole was in health. 



Guided bv this principle, I have made the human ear the 

 fuhject of ohfervation, and have endeavoured to af certain the 

 degree of lofs it fuftains in its powers by the want of the 

 membrana tvmpani; a membrane which has been generally 

 confidered, from its Situation in the meatus, and its connec- 

 tion with the adjacent parrs by a beautiful and delicate ftruc- 

 ture, as elTentiaily neceflarv to the fenfe of hearing; but 

 which, as appears by the following obfervations, may be 

 loft, with little prejudice to the functions of the organ. 



Mr. P , a medical ftudent at St. Thomas's hofpital, 



of the age of twenty years, applied to me, hi the winter of 

 1 797, while he was attending a courfe of anatomkal lectures, 

 requefting my opinion upon the nature of a complaint in his 

 far, which had long rendered him flightly deaf. 



Upon inquiring into the nature of the fvmptoms which, 

 had preceded, and of thofe which now accompanied the 

 difeafe, he informed me, that he bad been fuhject from his 

 infancy to pains in the head, and was attacked, at the age 

 of ten years, with an inflammation and Suppuration in the 

 ' left ear, which continued discharging matter for feveral 

 weeks :- in the fpace of about twelve months after the firffc 

 attack, fymptoms of a fimilar kind took place in the right 

 tar, from which alfo matter il'fued for a considerable time. 

 i'iie di (charge in each in [lance was thin, and extremely of- 

 fensive to the fmell ; and, in the matter, bones or pieces of 

 bones were obfervablc. The \m confequence of thefe 



attacks was a total deafn-cSs, which continued tor three 

 tfnonths; the hearing then began to return, and, in about 

 ten months from the latt attack, was rcftored to the ftate ire 

 which it at prefent remains. 



Having thus defcribed the difeafe and its fymptoms, he 



gave me the f ig each membrana 



tvmpani being imperfect. Having filled his mouth with air,, 



clofed the noftrils and contracted his cheeks: the air^ 



thus caraprefled, v. as heard to ruth through the meatus 'au- 



ditoriu9 



