Diseases of the Bone. 241 



of "proud flesh/' which is not attached to the sides, but only 

 to the bottom of the ulcer. There is a watery and offensive 

 discharge, but as this flows inside the mouth and becomes 

 mixed with the saliva, often the only circumstance wdiich 

 calls attention to the presence of the disease is the bleeding 

 from the mouth when the bit is in place. The mouth is full 

 of a slightly bloody pink froth. 



This form of caries is best treated by ceasing to use the 

 bit, and touching the sore repeatedly with the nitrate of sil- 

 ver stick, wdiich should be pushed deeply into it and held 

 for a second or tw^o. By judiciously continuing this for a 

 few W'Ceks, taking care not to use the caustic more than 

 enough to keej) down the proud flesh, a cure can be effected 

 without the necessity of cutting down and scraping the bone. 

 Nevertheless, wdien time is an object, the latter is much the 

 more expeditious plan. The horse should be cast, and 

 chloroformed, the granulations removed with the knife, the 

 dead bone scraped away, and the wound swabbed with, the 

 solution of chloride of zinc. 



FSOSTBITE. 



This is caused by prolonged exposure to the cold, espe- 

 cially by standing in the snow, and in half-thawed slush, as 

 is so often the case in the cities. 



The skin of the part becomes weaker, turns of a purple 

 color, is easily inflamed, cracks, and discharges a bloody- 

 looking fluid. 



In more severe and sudden cases the skin and underlying 

 tissues become pale, insensible and shriveled. The skin, 

 particularly on the heel, will slough across from side to side, 

 forming a deep crack, a condition familiarly called "cracked 

 heel.'' 



Treatment. — Where the skin is unbroken, and the ex- 

 posure has not been for a long enough time to destroy the 



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