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firm leathern strap. When the horn is thick, more especially when the 
fissure is seated at the toe, the nailing method of clasping is very useful. A 
notch is cut about half an inch on each side of the crack, about a quarter of 
an inch in depth. Several other notches may also be made at intervals of 
about an inch, if the crack is a long one. Then, by the aid of a skilled 
smith, horse. nails are driven from one side to the other, and their parts are 
drawn together tightly by pincers, and the ends rasped down. When 
situated at the toe, a hole may be bored under the crack, and a nail passed 
through and similarly clenched. When the crack is cured, it is necessary to 
use flat shoes, and to remember never to allow the smith to thin the sole. 
‘ 
CANKER. 
CANKER is a disease characterised by the abundant discharge of thin fetid 
matter from the frog and sole of the foot, and by the presence of large 
fungoid granulations, or pallid irregularly shaped elevations, occupying the 
place where healthy horn should grow. When examined with the 
microscope, these elevations appear to consist chiefly of imperfectly formed 
horn cells ; and this would lead us to infer that the horny matter itself was - 
improperly secreted, owing to abnormal changes in the membrane. 
Canker most probably depends upon inflammation, and consequent 
alterations in the membrane, which secretes the horny sole and frog, and 
covers the coffin bone. The disease usually commences in the frog, 
extending to the sole, and sometimes involving the sensitive lamin, which 
secrete the inner part of the wall of the hoof. Sometimes, the diseased 
action is confined to one foot, but in other cases it affects two; and the 
writer has not unfrequently met with cases in which all four feet were 
involved. The hind feet are more frequently affected than the fore ones. 
_ Canker is very rarely seen except in cart-horses, in which it is not at all an 
uncommon disease. Regarding the causes of this affection of the foot, it has 
been suggested by Percivall, that some horses, more especially bulky animals 
of sluggish: lymphatic temperament, are peculiarly predisposed to become 
affected; and it is in such animals that the affection termed grease is 
also especially liable to appear. 
Sometimes, canker has its origin in a neglected injury to the foot, in 
which case it will be confined to the wounded member. Not uncommonly 
‘it is traceable to standing on damp and filthy bedding, and to generally bad 
sanitation. 
In canker the horny sole of the foot becomes gradually separated from 
the membrane which secretes the horn, and, as the unhealthy action spreads, 
the whole of the sole is thus undermined. Canker is a very difficult disease 
to treat successfully, and it is therefore advisable to call in the best 
professional aid. In severe forms, the operation of cutting away the sole is 
generally necessary. We shall not describe the operation, but we may 
mention that it consists in taking away the whole of the horny sole of the 
foot, and the unhealthy growths by which it is undermined. Afterwards, the 
