484 THE HORSE. 
glottidis) an2 altered and diminished, are sure to have a prejudicial 
effect upon the wind, and either to produce roaring, whistling, wheezing, 
or trumpeting, but which would result it might be difficult to say, 
although the precise condition of the larynx were known, which it cannot 
be during life. Until recently veterinary surgeons were puzzled by often 
finding on examination of a roarer’s larynx after death no visible organic 
change in the opening, and many were led to imagine that this part could 
not be the seat of the disease. On a careful dissection, however, it is 
found that a muscle or muscles whose office it is to dilate the larynx is 
wasted and flabby (crico-arytenoideus lateralis and thyro-arytenoideus). 
The other muscles are perhaps equally atrophied, but as their office is to 
close the opening, their defects are not equally injurious, and at all events 
are not shown by producing an unnatural noise. The cause of this 
wasting is to be looked for in pressure upon the nerve which supplies 
these muscles, and which passes through an opening in the posterior ala of 
the thyroid cartilage, so that whatever causes a displacement of that part 
will mechanically affect the nerve. For these several reasons it will be 
necessary to examine first of all into the several kinds of inflammation, 
&c., to which the larynx is subject, and then to investigate as far as we 
may, the nature, mode of detection, and treatment of the several condi- 
tions known to horsemen by the names of roaring, whistling, &c., which 
are only symptoms of one or other of the diseases to which allusion will 
presently be made. 
By ACUTE LARYNGITIS is meant a more than ordinary inflammation of 
the larynx, and not that slightly morbid condition in which the mucous 
membrane of that organ is always involved in ‘the passage of a cold into 
the chest.” In the latter state the ear detects no unusual sound, and 
indeed there is plenty of room for the air to pass. But in true laryngitis, 
on placing the ear near the throat, a harsh rasping sound is heard, which 
is sufficient at once to show the nature and urgency of the symptoms. 
The mucous membrane is swollen, and tinged with blood; the rima 
glottidis is almost closed, and the air in passing through it produces the 
sound above described, which, however, is sometimes replaced by a 
stridulous or hissmg one. In conjunction with this well-marked 
symptom there is always a hoarse cough of a peculiar character, and 
some considerable fever, with frequent respiration, and a hard, wiry 
pulse of seventy to eighty. The treatment must be of the most active 
kind, for not only is life threatened, but even if a fatal result does not 
take place, there is great danger of permanent organic mischief to the 
delicate apparatus of the larynx, generally from the effusion of lymph 
into the submucous cellular membrane. A full bleeding should at once 
be practised, and repeated at the end of twelve hours if there is no relie! 
afforded and the pulse still continues hard. The hair should be cut off 
the throat, and the tincture of cantharides brushed on in a pure state until 
a blister arises, when the part may be constantly well fomented, to encou- 
rage the discharge. Large doses of tartar emetic, calomel, and digitalis, 
must also be given, but their amount and frequency should be left to an 
experienced veterinarian, the prelirzinary bleeding and blistering being 
done in his absence to save time. It is a case in which medicine must be 
pushed as far as can be done with safety, and this cannot well be left to 
any one who is not well acquainted with its effects, and with the powers 
of the animal economy. Gruel is the only food allowed during the acute 
stage, and there is seldom time to have recourse to aperient physic until 
the urgent symptoms are abated, when an ordinary dose may be given. 
