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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 coflin bone. The disease usually commences in the frog, 

 extending to the sole, and sometimes involving the sensitive laminic, 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 wdiich 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 

 rnention 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 



