416 STABLE MANUAL AND HORSE DOCTOR 



the bars When violent pressure is applied, even for a 

 short time, it produces inflammation and extravasation from 

 the secreting sole, the vessels of which becoming ruptured, 

 a "sappy" or "bleeding" corn, called a "new corn," makes 

 its appearance, presenting a blood-marked spot. The sup- 

 purating corn we will notice presently. The sensible sole 

 thus injured, unless immediately relieved, and not again 

 subjected to pressure until perfectly reinstated, takes on a 

 permanently diseased state. Ever after, instead of perfect 

 horn, a morbid secretion is deposited, and in some cases a 

 semi-purulent matter, or pure pus, fills up the place, the 

 inflamed vessels retaining an exquisite sensibility. 



Corns are usually found upon the inside of the foot, 

 because the inner wall and heel are weaker, and also bear 

 a greater portion of weight than the outer. The coffin-bone 

 not reaching to the heels is the reason why these structures 

 are the seats of corn, for the coffin-bone is the active agent 

 in its production. This bone is moved upwards and down- 

 wards at either end, as the weight rests upon one extremity 

 or the other of its articular surface. It is the wings of the 

 coffin-bone which cause corns. The descent of these wings 

 squeezes the sensitive sole between them and the shoe in 

 open feet, the shoe in this case being the passive agent ; but 

 in the contracted foot, the high, thick, hard, and unyielding 

 sole becomes the passive agent, and between that and the 

 wing of the coffin-bone the sensitive sole is bruised. Too 

 little horn subjects the feet to corns, because a sHght 

 pressure will indent weak feet. The best shoe, suffered to 

 remain on a foot too long, will produce a corn, or corns. 



Neglecting to prepare the foot for the shoe is also a 

 fruitful source of corns ; for, in preparing a foot, this 

 angular portion should be so pared as to remove it from 

 contact with the iron, without weakening the horny cover- 

 ing of the sensible sole. Another common cause is the 

 neglect of removing or renewing the shoes at proper intervals. 

 When a shoe has been long worn, the growth of the hoof 

 carries it forward, by which the parts originally opposed 

 to the heels are carried beyond them, and now press on the 

 sole, often becoming indented within the line of the crust, 

 and producing a most injurious pressure. Sometimes, also, 

 either from the original form of the shoes, or by long wear, 

 they become loose, or " springy " at the heels, as smiths call 

 it ; in which case gravel is apt to make its way between 



