REMARKS ON AUSCULTATION. 
565 
other stethoscopes with the same result— I found that I could hear 
with these different stethoscopes distinctly enough the respiratory 
action in man, but in the horse, cow, dog, cat, &c. I was at fault ; 
while, with the naked ear, without any assistance, I could make 
out very distinctly the different sounds produced in the chest. I 
therefore, after a very patient series of experiments, abandoned 
the stethoscope, and depended upon my ear alone. I have no 
doubt the cause of the failure of the instrument arises from the inter- 
position of the hair, not only from its being a non-conductor of sound 
in itself, but from its leaving a vacuity between the open extremity 
of the stethoscope and the skin, which allows any sound, that might 
otherwise be transmitted, to escape, as well as extrinsic sounds to 
enter the tube. I have tried various methods to obviate this dif- 
ficulty, — -a silk or linen handkerchief very tightly strained, and 
pressed firmly over the side, but with no good effect. I have at 
various periods repeated these experiments, but always with the 
same results. I now, therefore, depend upon the ear alone, and, 
whenever it is possible, without any thing (except the hair) to im- 
pede the sound. It is sometimes, however, requisite, in conse- 
quence of the effects of blisters, &c., to make use of a covering ; 
in which case I use a thin linen rubber, or cloth, because the most 
generally to be procured, and this I have smoothly and tightly 
strained over the part I wish to examine. By this means I am 
enabled to make examination at all times : and so confident am I 
of the nature of the auscultation, that I never like to give an opi- 
nion before I have had recourse to it : I even find it of service in 
making an examination as to soundness, where much nicety be- 
comes requisite. 
Before any correct diagnosis can be formed, it is requisite that 
the sounds produced by respiration in animals in a state of health 
be understood. In their normal condition the lungs will be found 
to be pervaded equally throughout with a murmuring sound. 
When this murmur is unequal, or less distinct at one part than 
at others, it may be fairly presumed that that portion which has 
the least murmur is the part wherein the greatest degree of dis- 
ease exists. So, also, in regard to the sounds produced in the 
abdominal viscera, it is requisite to know the nature of the sound 
occasioned by the vermicular action of the bowels during ordinary 
states of health, and thus, by comparison, will visceral derange- 
ment be detected. 
But there is one point that must not be lost sight of ; for unless 
that be pretty well understood, the other knowledge will be but of 
little avail, that is ANATOMY. Without a knowledge of the rela- 
tive position different parts occupy, an acquaintance with the part 
VOL. XIX. 4 H 
