366 DADD'S VETERINARY MEDICINE \ND SURGERY. 
and canals are filled with material resembling soft cheese, which 
ts probably fatty matter. This occasionally degenerates into pus. 
Dr. Gorpon forwarded me, some time ago, the head of a herse 
who kad long been the subject of this malady. The transverse 
diameter of the bones of both upper and lower jaw was very much 
enlarged; the periosteum was very highly organized with blood- 
vessels; the bones were softened and elastic, and could be easily 
eut with a knife. On submitting them to the acid test, earthy 
matter was found in excess, and, by burning them, it was found 
that they contained very little animal matter; hence we were led 
to infer that the disease was one of mal-nutrition. The articular 
surfaces of various bones, and sometimes all the bones of the body, 
are often ulcerated and studded with incrustations. This expleins 
the why and wherefore of the sudden and tormenting pains wh ich 
animals suffer, and goes to show how little of benefit can be ex- 
pected from the ordinary treatment, which is principally dire ted 
to the enlarged jaws. 
On removing these diseased cartilages from the articulating 
surfaces of the bones, the latter are found to be affected—in fact, 
ulcerated. In some cases the ligaments and tendons are separated 
by decomposition, or necrosis of bone, and the animal “ breaks 
down,” as the saying is. 
The subjects of this disease sometimes show lameness in the 
vertebral region, and in that of the head of the thigh bone. Ia 
such cases, we may safely infer that the lameness is of an articular 
character, and the interticular cartilages, as well as the surfaces of 
the bones, are incrustated and ulcerated. In this condition, the 
animal is liable to become useless, or “break down” at any mo- 
ment. The following case will illustrate what is meant by break- 
ing down: 
We were requested, a short time ago, by Prof. Muzzy, to ex- 
amine an aged gray gelding, the subject of lameness in the hind 
feet. Examination revealed considerable heat, tenderness, and 
tumefaction around both the hind coronets, and both angles of the 
lower jaw were much enlarged in their transverse diameters. We 
advised the owner to let the animal have arun at grass. Accord- 
ingly he was sent into the country about thirty miles, which was 
too long a journey for him. A few days afterward, Prof. Muzzy 
received a letter that the horse’s strings (tendons) became loose, 
ana he broke down and traveled on his fetlocks. and was thes 
