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no disease of the coronary substance from which the wall is 

 secreted. 



It chiefly occurs in weak, brittle, light colored feet, where 

 the rasp is used at every shoeing, and often comes on sud- 

 denly as the result of concussion on a hard road. This 

 accident may happen in an instant from a false step. It 

 occurs in both fore and hind feet. Its situation in the first in- 

 stance is the inner quarter ; in the second, the front or near 

 the toe, the principal stress coming on that part in the hind 

 foot. It always constitutes unsoundness. 



The depth of the crack or fissure determines the lameness. 

 When it is merely superficial there is no lameness, but when 

 it penetrates to the quick pain and lameness ensue. The 

 opening sometimes extends to the eighth of an inch, bloody 

 serum exudes, and proud flesh sprouts from the crack. A 

 case of this kind is difficult to cure. 



Even when the opening is not so deep as this sand and 

 dirt constantly enter, and act as irritants to the sensitive 

 structure beneath, when after some time fungous growths 

 may appear from the sandcrack. 



Treatment. — The present treatment of sandcrack is 

 chiefly mechanical. The crack is thoroughly cleaned out, 

 the dirt and foreign matters removed with a bit of wire 

 covered with a little oakum, the wash consisting of diluted 

 carbolic acid. The horn on each side of the crack is very 

 slightly pared ; this much is only a preparatory process. 



To hold and retain the divided parts of the hoof together 

 a very ingenious contrivance is used. This is a French 

 invention, and is simply a piece of thick fine steel wire, half 

 an inch long, with a claw on each end. In order to make a 

 proper opening in each side of the divided wall, for the 

 entrance of these claws, there is an iron adapted for the 

 purpose; this is heated red-hot, and the two holes are 

 burned into the wall at the same time. When this is done 

 the claws of this little contrivance are gently tapped into 

 their places. These are sold by most surgical instrument 

 makers. 



