118 
ON DISEASES OF THE LUNGS IN HORSES. 
Nasal Cavities. —The ear, applied to the nostrils of horses, even during 
repose, hears such a sound as condensed air streaming through some hollow 
tube would produce ; but through the parietes of the nasal chambers, or the 
sinuses of the head, no sound whatever can be detected, either by the ear or the 
stethescope; unless after exertion, and then a sort of snoring sound is heard 
in the former, while in the sinuses a soft murmur only is audible. A tumid 
condition of the Schneiderian membrane gives rise to the sound of thick wind, 
which augmented becomes whistling; and this may exist either on one or both 
sides. Sounds emanating from the larynx, windpipe, or bronchial tubes, or 
even from the recesses of the lungs, sometimes retain their force to that de¬ 
gree within the nasal chambers as to lead us to believe they arise there. Such 
mistakes are easily corrected by applying the ear by turns to the larynx, neck, 
and chest, the sound being greatest opposite to where it is produced. Snort¬ 
ing, which may be excited at any time by momentarily closing the nostrils, 
and which is occasionally thus produced to cause the ejection of matter from 
the nasal chambers, may be put in practice by way of .further testing the seat 
of sound. 
The Sinuses of the Head, tested by percussion, either with the finger 
doubled, or with a key, or a piece of wood, or, what is better, with a small 
hammer and a light wooden shield interposed, yields in the young horse but 
indistinct resonance; the sound is plainer in the adult, but loudest of aU in 
the old: a difference no doubt ascribable to the changes the sinuses undergo 
with age. As the resonance of the nasal chambers is diminished by the pre¬ 
sence of poh’pi, or the accumulation of pus, so is that of the sinuses by even 
but a small purulent collection. Purulent repletion completely deadens sound. 
At the same time percussion becomes painful, -and the frontal bone often 
convexed. 
The Larynx, in a state of health, yields but a faint sound to the ear. 
Under disease, however, we may with Leblanc regard the anormal sounds as 
consisting,—1st. In a dry whistle^ which is the result of contraction, either 
from conformation or,compression, or of physical or vital lesion of the recur¬ 
rent nerve. 2d. In a humid whistle^ the consequence of a tumid membrane 
covered with mucus, which is sometimes intermittent and accompanied with 
a guggling noise or mucous rdle^ as in acute laryngitis. 3d. In a rale which 
may be either dry or humid, audible either at the beginning or decline of la- 
ryngitic inflammation. 
The Windpipe yields but little to our listenings, unless it be at the 
superior and inferior parts. At its entrance into the chest, in the normal 
condition, is heard the sound of soft blowing, most prolonged during expira¬ 
tion. This respiratory sound, which is occasioned by the air returning from 
the bronchial tubes into the windpipe, we call, from its situation, tracheo- 
bronchial respiration. Frequency of respiration increases it. When liquids 
become effused into the bronchial tubes, the mucous rale is heard; and this 
is often accompanied by the sibilant rale and by the sonorous rale. In case 
of effusion of blood into the tubes, the rale is spumous. 
The Thorax affords no information to the feel, except in the case of pleu¬ 
risy, and then the animal sensibly flinches from pressure sharply applied 
against the intervals of the ribs. Oxen will even moan from the pain occa¬ 
sioned. Neither admeasurement nor succussion of the chest produce any satis¬ 
factory results. 
Percussion of the Thorax means striking or tapping its sides with a view 
of judging, from the different sounds elicited, of the normal or anormal condi¬ 
tion of the organs within. The chest is said to resound when the vibrations 
raised by the shock extend throughout the chest and the contained viscera: 
on the contrary, when they appear confined to the place .struck, it is said not 
