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except. at the heel; and corns result.”. The seat of corns is just that 
part where the heey sole is thinnest, and consequently most liable to injury. 
If the bars have been cut down, and the heels allowed to grow unduly long, 
coms are more likely to be produced. It must, however, be mentioned that 
corns are not unfrequently met with in feet -in all other respects healthy ; 
but in most instances they only appear as the result of defective methods of 
shoeing. When the sole is very weak, or has been unduly thinned, corns 
are naturally more liable to be produced. Sometimes owing to a space left 
‘between the shoes and the horny heel, dirt insinuates itself, and pressing on 
the seat of corn causes the appearance of these bruises. We have already 
exposed that most pernicious and barbarous custom of stopping horses’ feet 
with decaying matter; and we only allude to it again, to state that by 
macerating and weakening the horny sole of the foot, it thus renders it far 
more liable to be injuriously affected by bad shoeing or fast trotting on hard 
ground, or by any other direct cause. “Stopping” feet is therefore an 
indirect cause of corns. It is, we wish to point out, not merely owing to the 
fitting on of the seated shoe, which we have said is so frequently the cause 
of corns, but also to other mistakes which the smith commonly makes, that 
these bruises make their appearance. Not uncommonly he pares away the 
bars, and by this practice, the foot tends to become contracted ; and the 
pressure of the heels of the shoe falls upon the spot indicated as the seat of 
«corm. Lastly, we may add that the use of calkins, and the practice of not 
renewing the shoes often enough, are to be regarded also as occasional 
factors in the production of corns. When a shoe is not removed as often as 
is necessary, and is on the contrary allowed to wear down, it may be 
removed from its original position, and press upon the seat of corn. 
A corn constitutes unsoundness, because, although it may not cause 
lameness in all instances, or at all times affect progression, yet, until cured, 
the animal may become so much worse, as to be wholly unfit for work. Rest 
for several days will often render the horse free from lameness for a time. 
‘Asa rule, there will not be much difficulty in diagnosing a case of lameness 
when dependent upon corns. When the horn at the seat of a corn is pared 
away by the smith, a reddened patch becomes visible, and renders the 
diagnosis certain. In some casés—and these are not uncommon—all that 
can be discovered, besides the manifest lameness, is merely an increased 
sensibility of the sole at the seat of the corn. There is no red patch of 
effusion, for this necessarily depends upon actual rupture of some vessels of 
the sensitive sole, consequent upon a severe contusion. As the smith pares 
the sole still more, the reddened patch may be found to extend completely 
into the quick ; or, on the other hand, it may be merely superficial. In the 
former case the bruise is of recent origin, while in the latter it is of older 
Standing. 
We mentioned, in treating of inflammation, that serous fluid is poured 
out of the little blood-vessels of the affected part. This is the case when the 
sensitive sole is inflamed. A yellowish fluid oozes through the corn, and 
moistens the horny sole around. Sometimes so severe are the inflammatory 
