LAMENESS IN HORSES. 
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said, by intensity or continuance, to give rise to the other. 
This is the usual notion of the production of canker; but it is 
one which, for my own part, I cannot altogether reconcile with 
the results of experience. We know that horses will have 
frushes, and very bad frushes, for years together, to which no 
medical attention is paid, and yet canker never supervenes. 
On the other hand, we learn from observation that horses in 
certain situations can hardly have frush without canker speedily 
ensuing, unless prompt and efficient means be taken to prevent 
it. In hot, foul, ill- ventilated stables this is found to be the 
case. Let horses stand with their feet in the filth and muck of 
uncleansed stables until they contract frushes, and let their 
frushes go on unattended to, and canker will be the pretty cer- 
tain result. This is the reason why the hind feet are more 
subject to canker than the fore. Or, let horses remain during 
the winter at straw-yard or in wet pasture, and while their hoofs 
are becoming frushy, abandon them altogether to “ take their 
chance,” and canker will be sure to be the consequence. All this 
would seem to shew that the secretory apparatus of the foot may 
from such influences as heated and foul and impure stabling 
affords, or simply from continued exposure to wet and dirt, lose 
their power of producing sound horn, or indeed horny matter at 
all, and in lieu thereof pour forth the matter peculiar to canker, 
we call fungus. 
Although frush is the ordinary forerunner of canker, still 
may and does the latter issue out of other local causes Grease, 
from the matter trickling down over the heel into the cleft of 
the frog, may give rise to disordered action of that part, which, 
sooner or later, may end in the production of canker. Quittor 
likewise, it is said, may produce it; though this is an effect 
I have had no evidence of myself. In a foot disposed to take 
on cankerous action, there can be no doubt but that any lesion of 
frog or sole may be followed by the disease. By far, however, 
the most common origin of the disease is said to be in frush. 
Pathology of Canker. — Close observation during life has 
shewn, while post-mortem examination has confirmed the fact, 
that the horn-producing — the keralogeneous — organ is the part 
specifically diseased in canker, and to this delicate tissue and 
its soft substrata, the cellular coverings of the frog and sole, 
the disease is confined : neither bone, nor tendon, nor cartilage 
being found implicated in its spread. On this part of my sub- 
ject I rejoice to have an opportunity of deriving information 
from a very interesting report obligingly made of a cankered 
foot, which had been submitted to him by M. Bouley, by 
M. Robin, Professor of the Faculty of Medicine at Paris, who, 
with the aid of the microscope, found “ that the anatomical 
