as a Means for curing Deafness. 23 



nnd re-established the equilibrium. Through the left Eustacliinn 

 tube no air liad yet passed, and the pain in the left ear was 

 gradually increasing. When about fourteen feet undi r water, the 

 sensation was as if a stick was forced into that ear from without. 

 At last, during one of the exertions to open the mouth of the 

 Eustachian tube on that side, the air forced its wav with consi- 

 derable violence through it, and I was relieved of the pain also 

 on that side. 



After examining the mason- work of the pier at the bottom of 

 the sea, I began to ascend. Here I soon felt pain again, re- 

 .sulting from the air in the inner ca\ itv of the ear expanding, as 

 the external pressure diminished: but this pain was more easily 

 relieved, the air gushing at very short intervals without any 

 voluntary exertions in small portions from the ear through the 

 Eustachian tube into the mouth. 



Noticing this, it occurred to me, that the diving-bell might be 

 used for curing deafness in those cases where it depends on 

 an obstruction of the Eustachian tube. The patient v/ould 

 have to go down in a diving-bell and make those exertions 

 which open the mouth of the Eustachian tube, and then the 

 pressure of the condensed air would force its wav through the 

 extent of the tube, and by that means clear the passage. It is 

 well known, tliat slight obstructions have been frequentlv re- 

 moved, by forcing air or tobacco-smoke from the cavity of the 

 mouth into the ear. When I was in the diving-bel', and m.ade 

 my exertions to admit air into the Eustachian tube, I was not 

 aware of the simple wav in which it is effected. Dr.Wollaston 

 informed me, that notliing is wanted but to swallow the saliva, 

 as may be seen from the following simple and easy experiment. 

 Close your nostrils with your fingers and suck with vour mouth 

 shut ; air will come throiigli the Eustachian tube from the 

 ear, and you feel pressure on tlse meml)rana tvmpani, which 

 prevents you fioni hearing dislinctiy. As the end of the Eusta- 

 chian tube nearest to the mouth acts like a valve, this sensation 

 will often remain even after you have ceased sucking. To remove 

 it, nothing is wanted but to swallow saliva, whereby the action of 

 the muscles seems to open the end of the Eustachian tube, and 

 then the air rushes in to re-establish the equilibrium. This ex- 

 periment shows on a small scale part of what I experienced in 

 tlie diving-bell ; where, to admit the air into the ear. one must 

 merely swallow saliva, and at one of these exertions the air will 

 ru^h in, if the obstruction be not very considerable. 



I was anxious to know, whether men that had been in diving- 

 bells before, had noticed the same sensations as myself, and I made 

 tliem describe to me what they had felt. Among other things 

 they vtattd, that when at a great depth it had been to them " as 

 B 4 if 



