THICK WIND. 
403 
been compressed, destroyed ; the minute ramifications of the pul¬ 
monary arteries have been compressed, destroyed ; and one uni¬ 
form mass has resulted, which is now taken up by the absorbents, 
and instead of the restoration of the primary air-cells, with their 
mesh-work of innumerable vessels, we have larger or smaller ca¬ 
vities—ulcerations—voraicee. There are few cases of old hepa¬ 
tization in which there are not some parts in a state of softening ; 
and the cases are numerous in which the vomicae have been very 
extensive, wdiile nothing has indicated their existence. Indeed, 
when we consider that they happen in a part already removed 
from the function of respiration, and furnished with organic nerves 
alone, or with few sensitive fibrils, w’e need not wonder that this 
secondary change should proceed so far, and we remain perfectly 
unconscious of it. 
Advantage of Auscultation. —This brings me back to a circum¬ 
stance on which I have already laid much stress—the habitual 
and anxious recourse to auscultation in every inflammatory 
affection of the chest. We may guess at the commencement of 
that congestion which precedes hepatization, by the laborious 
heaving of the flanks ; but by auscultation alone can we ascer¬ 
tain its commencement and progress. The increase of the cre¬ 
pitus will tell us that the mischief is beginning, and the cessation 
of the murmur w ill clearly mark out the extent of the congestion. 
•The inflammatory stage of the disease having passed, and 
comparative health being restored, and some return to usefulness 
having been established,—the horse being now thick winded, 
auscultation will be far more valuable than is generally imagined. 
It will faithfully indicate the extent of the hepatization, and so 
give a clue to the degree of usefulness, or the degree to w’hich 
we may tax the respiratory system ; and it will also serve to 
distinguish, and that very clearly, between this cause of thick 
wind, and the morbid changes that may have resulted from 
bronchitis, or the thickening of the parietes of the air-passages, 
and not the obliteration of the air-cells. This leads me to the 
consideration of a second cause of thick wind. 
Thickening of the Lining Membrane of the Bronchiw. —I have 
described bronchitis as inflammation of the linino^ membrane of 
^ o 
the bronchial tubes. I need not tell you that one of the tests of 
inflammation is tumefaction, increased deposition in the sub¬ 
stance of the part inflamed. This is peculiarly exemplified in 
bronchitis ; the thickening and the sensibility of the membrane 
produce in that disease a disturbance in respiration unknowm in 
any other malady, and almost incredible. It wall often be found 
that this unnatural deposition, this thickening of membranes, 
will not always subside with the subsidence of the inflammation. 
