76 SURGICAL APPLIED ANATOMY. [Chap. v. 



eye. How such a treatment can act, if it acts at 

 all, is hard to understand. It is true that the main 

 nerve supply of the eye and of the conjunctiva comes 

 from the fifth nerve, but, unfortunately for any nerve 

 theory, the lobule of the ear is only supplied by the 

 great auricular nerve. If the ear-ring, in such cases, 

 were introduced through the upper part of the ear, 

 supplied as it is in front by the fifth nerve, some 

 connection might be traced. 



Hilton reports a case of obscure pain in the ear 

 which was found to be due to an enlarged gland in the 

 neck, that pressed upon the trunk of the great auri- 

 cular nerve. 



Jttembrana lyiujmiii. This membrane is very 

 obliquely placed, forming with the horizon an angle 

 of 45. At birth it appears to be more nearly hori- 

 zontal, although it is not really so. In cretins, and 

 in some idiots, it is said to retain this apparent in- 

 clination. Owing to the sloping downwards of the 

 bony wall of the meatus at its inner end, that wall 

 forms with the lower edge of the mernbrana a kind of 

 sinus in which small foreign bodies may readily lodge 

 (Fig. 12). The ring of bone to which the membrane 

 is attached is deficient at its upper and anterior part. 

 The gap so formed is called the notch of Rivini, and 

 is occupied by loose connective tissue, covered by a 

 continuation of the lining of the meatus, and through 

 it pus may escape from the middle ear into the 

 auditory canal without perforating the membrane. 

 When the membrane gives way owing to a violent 

 concussion transmitted through the air, it often gives 

 way opposite the notch, its attachments here being 

 obviously less secure than elsewhere. The membrane 

 possesses but little elasticity, as shown by the very 

 slight gaping of the part after it has been wounded. 

 Tt is for this reason, among others, that perforations 

 rjiade in the membrane by the surgeon heal so very 



