56 
QUITTOR. 
hard, tumid, and very painful, but there was no discoverable 
lesion. (Fomentations, emollient poultices, rest.) The animal 
recovering his soundness, although the tumefaction remained, 
was put to work again. Lameness however was reproduced, 
and I was called on to revisit him. I found matter exuding 
amongst the hair; a swelling rising into a prominence upon the 
coronet, fluctuating at several points : and the horse hardly able 
to rest any weight at all upon the limb. I hesitated not to re¬ 
move the cartilage : it was almost entirely separated from the 
subjacent tissues by a considerable collection of greyish matter, 
very thin and little odorous. Its substance showed no signs of 
caries, but the surface was merely softened in several places : 
the capsular ligament was opened in the operation. The issue 
of synovia ceased at the third dressing; and notwithstanding 
this accident the horse was put to light work, upon soft ground, 
five weeks after the operation. In the beginning of the third 
month, the wound w^as wholly covered with sound horn, and 
scarcely any trace of the operation was discoverable. 
Let us now turn our attention to the anatomical structure of 
the lateral cartilages of the foot, and see if that will furnish us 
with reasons why the corrosive sublimate has not been equally 
successful in all the foregoing cases. This inquiry I trust will 
prove that such different results from the same cause might 
have been apprehended, if not foreseen ; since they are but the 
natural consequences of the organization of these cartilages, 
which will be found not to be alike in every part. 
Repeated examination of it anteriorly and towards its base, 
only goes to confim its similarity to other cartilages, properly so 
called : it is white, flexible, frangible, and homogeneous. As 
we approach the borders and the posterior part, it loses its ho¬ 
mogeneous characters: it is no longer frangible; and in being 
rent discovers a fibro-filamentous texture. Still more poste¬ 
riorly, the fibro-cartilaginous organization is more manifest, and 
here, on an attentive view, seem to exist isolated cartilaginous 
knobs, surrounded by substance entirely fibrous. Lastly, the 
extreme posterior end is fibro-adipose, and is confounded witJi 
the fatty frog. Now, if we recall to mind—1st. that the carti¬ 
laginous tissue possesses but in a very low degree the vital pro¬ 
perties; (contractility, sensibility;) 2dly. that inflammation 
excited within it by external irritation, proceeds very tardily 
and commonly ends in caries; 3dly. that caries spreads so long 
as any continuous cartilage is left—it will not be difficult to ex¬ 
plain the first part of the problem. For instance, admit that 
caries is already established within the anterior part, or in the 
base, of one of the lateral cartilages : the mortified spot in such 
tissue will communicate irritation and consequent caries to all 
