64 
MR. YOUATt’s veterinary LECTURES. 
be produced, to be a cause of roaring. The foundation of roar¬ 
ing,—the ossification of the cartilages,—previously existed, and 
produced the difficulty of compressing the larynx, so as to excite 
the horse to couch. 
O 
The Disease of Draught-Hoi'ses generally. —There can be no 
doubt of the fact, that the majority of roarers are draught-horses, 
and horses of quick draught. They are not only subject to the 
usual predisposing causes of this obstruction, but there is some¬ 
thing superadded, something resulting from their habits or mode 
of work,—not indeed necessarily resulting, but that which the 
folly as well as cruelty of man has introduced; I mean the 
system of tight-reining,—the continued and painful pressure 
upon the larynx, by reining in the head of the horse, and teaching 
him to bear himself well. 
The Mischief of Tight-Reining. —I acknowledge that, to a 
certain extent, the curb-rein is necessary; without it w^e should 
have scarcely any command over a wilful horse, and it would 
need a strong arm always to guide even the most willing. With¬ 
out the curb-rein the horse would carry himself low; he would 
go carelessly along; he w’ould become a stumbler; and if he 
were disposed at any time to run away, the strongest of us would 
have no power to stop him: but there is no necessity for the 
tight rein, and for the long and previous discipline to which the 
carriage horse is subjected. There is no necessity that the lower 
jaw, whether the channel is wide or narrow, should be so forced 
on the neck, that the larynx and the portion of the windpipe im¬ 
mediately beneath it should be flattened and bent and twisted 
in the strangest way, and the respiratory passage not only ob¬ 
structed, but in a manner closed. Here we have a plain and 
palpable cause of roaring. The mischief is usually done when 
the horse is young. It is done in some measure by the im¬ 
patience of the animal, unused to control, and suffering pain. 
In the violent tossing and return of his head he bruises the larynx, 
and produces inflammation, while the constant pressure would 
flatten and distort. The head of the riding horse is gradually 
brought to its proper place by the hands of the breaker, who 
skilfully increases or relaxes the pressure, and humours and plays 
with the mouth ; but the poor carriage horse is confined by a rein 
that never slackens, and his nose is bent in at the expense of the 
larynx and windpipe; and the injury is materially increased if 
the head is not naturally well set on, or the neck thick, or the 
jaws narrow. Here are strange and almost incredible distortions 
of the larynx. Here are also some engravings of the laryrfx, in 
its natural and deformed state, which do credit to the ingenuity 
of Mr. Sewell. 
