1T3 
BRONCHITIS IN THE HORSE. 
Use of Auscultation in distinguishing the various Diseases of 
the Lungs. —Bronchitis is not generally a primary disease. That 
inflammation of the superior respiratory passages, constituting 
catarrh, gradually creeps downwards and involves the larynx and 
the trachea, and at length the farthest and the minutest ramifica¬ 
tions of the air-tubes. When you find that it is thus advancing, 
you will eagerly watch its progress by the assistance of immediate 
auscultation. Recollect the bellows-like healthy sound of the tra¬ 
chea ; that of the healthy lung resembles a deep and distant 
murmur. The very word expresses the sound. But the diseased 
lung! how shall you ascertain the seat, the degree, the conse¬ 
quence of inflammation? Careful attention to a very few cases 
will make you perfect masters of this. The distant murmur of 
the healthy lung you cannot mistake; nor the crackling crepi¬ 
tating sound of pneumonia,—inflammation ofthe substance of the 
lungs, or of the membrane lining the cells, or the compartments or 
divisions of the minute lobuli. You hear the blood filtering or 
breaking through these delicate membranes, and accounting for 
that congestion or filling of the cells with blood which is found 
after intense inflammation. The bronchi are lined by a mucous 
membrane, and, under inflammation, the secretion of mucus is 
increased, and the tubes are partially obstructed. The ear, ha¬ 
bituated to the exploration of the chest, will detect this wflth as 
much certainty as if the membrane had been fairly exposed to 
view, by the wdiizzing sound, as if the air w^ere forcing itself 
through a succession of bubbles. Inflammation precedes this 
increased discharge of mucus : even that may be detected. The 
inflamed membrane is thickened, tense; it assumes an almost 
cartilaginous structure, and the murmur is not only louder, but 
has a kind of snoring sound. Some have imagined that a metallic 
ring IS mingled with it. I have fancied something of the kind, 
but cannot say that it was distinct or convincing. 
Although we cannot yet carry this so far as the practitioner of 
human medicine does, we can derive most important advantage 
from the use of auscultation. We can at least ascertain the seat 
of inflammation : and the presence of the morbid sound, or the 
gradual recurrence of the healthy one, 'will point out the extent 
of the disease; while other indications, and obtained in the 
same way, will as faithfully tell us the mischief and disorgani¬ 
zation occasioned by the inflammation. Once more, gentlemen, 
let me urge you carefully to study the indications presented by 
immediate auscultation. They will rarely deceive you, and you 
will not have long accustomed yourselves to this mode of explo¬ 
ration without highly prizing it. 
Symptoms of Bronchitis. —The inteiTupted whizzing sound has 
