62 MR. youatt’s veterinary lectures. 
the supposed cause of it. Polypi in the nostrils have been ac¬ 
companied by it. Mr. Sewell found, as an evident cause of 
roaring, an exostosis between the two first ribs, and pressing upon 
the trachea; and Mr. Percivall goes further, and says that his 
father repeatedly blistered and fired a horse for bad roaring, and 
even performed the operation of tracheotomy, and at length the 
roaring being so loud when the horse was led out of the stable 
that it was painful to hear it, the poor animal w'as destroyed. No 
thickening of the membrane was found, no disease of the laiynx 
or trachea ; but the lungs were hepatized throughout the greater 
part of their substance, and many of the smaller divisions of the 
bronchi were so compressed, that they were hardly pervious. 
Bauds of coagulated Lymph. —A frequent cause of roaring is 
the bands of coagulated lymph, of which I have already spoken, 
morbidly viscid and tenacious from disease, adhering firmly on 
one side, and by some act of coughing brought into contact with 
the other side, and there adhering, and becoming gradually or¬ 
ganized, by means of the vessels which run into them from the 
membranes. At other times there have been rinos of coaoulated 
o o ^ 
lymph adhering to the liniilg of the trachea, but not organized. 
In either case they form a mechanical obstruction, and will ac¬ 
count for the roaring noise produced by the air, in hurried respi¬ 
ration, rushing violently through the diminished calibre. Here 
is a specimen of the transverse bands. 
Tracheotomy as a Method of Cure. —A veterinaiy^ practitioner 
resorted to the operation of tracheotomy, in order to find out and 
get rid of this band. He fortunately cut down upon it, and re¬ 
moved it, and the horse was no longer a roarer. The case was 
published, or gradually became known, and many others resorted 
to the same operation, but without success. Our first veterinary 
writer bears a little too hard upon this operation and the operator, 
and says that all the credit due to the first operator arose out 
of the dexterity he evinced in the operation; and that no little 
discredit was due to those who were silly enough to suppose that 
they might make a similar discovery wherever they chose to cut a 
hole into the windpipe.” Now, with submission to my valued 
friend, I do think that, if the cause of roaring exists in the trachea, 
we may discover the very seat of it, and cut a hole into the wind¬ 
pipe” directly upon it. We have that almost unerring guide, 
auscultation; we can, in a manner, assure ourselves of the spot 
whence the sound proceeds, and, consequently, where the ob¬ 
struction exists. We may not find a band there; it may only 
be thickening of the membrane : but in obstinate and very bad 
cases the experiment may be worth a trial. 
Thickening of the Membrane. —1 have just alluded to this as a 
