Patent Ear-trumpet. yi 
Arr. IV.—On a Patent Ear-trumpet and Stethosccpe,. 
invented by DAvip WILKINSON, Esq. 
[Read by Mr. C. Wilkinson, 8th October, 1866.] 
Mr. President and Gentlemen,—I have much pleasure in 
laying before you a new ear-trumpet and stethoscope, or 
rather I should say, some improvements on the ordinary 
instruments of this kind, invented by my father, Mr. David 
Wilkinson. He communicated his ideas to this society some 
three years ago, but as there were no instruments ac- 
companying his communication it does not seem to have 
been considered. Lately some of these instruments have 
been made and partially tested. 
In order, therefore, to make known that which may prove 
beneficial to many members of the community at large, 
whose welfare it is the chief object and desire of the Royal 
Society to promote, I could not do so in a more satisfactory 
manner than by submitting the following brief description 
to your consideration. ‘That the present construction of in- 
struments for conveying sound to the ear is but imperfectly 
adapted to the purpose, is evinced by the very partial relief 
they afford to those whose great adiiliction necessitates the 
use of them. 
I will here premise that it is not my intention to enter 
into the acoustic principles on which depend the proper 
construction of ear-trumpets ; nor to describe the anatomy 
of the ear; forit would be extreme presumption for one like 
myself, I must confess, so little acquainted with these 
scientitic subjects, to attempt to do so before the profes- 
sional members and others whom I have now the privilege 
of addressing. I will, however, allude to a few of the more 
simple points connected with these subjects, to which it will 
be necessary for me to refer in describing these instruments. 
Our perception of sound ordinarily results from the pulses 
or vibrations in the air conveyed by the various processes of 
the ear to the auditory nerves, whence the impressions pro- 
duced are communicated to the brain where their effects arc 
realized. 
The principal parts of the ear are the outer-ear, the drum 
of the ear, and the sensorium, or inner-ear. The outer-ear 
seems formed as it were like an ear-trumpet, to catch the 
vibrations in the air and conduct them toa tube, through 
