422 DISEASES OF THE HORSE. 



of necessary moisture ; this, in turn, reduces the elastic properties of 

 the horn and diminishes the transverse diameter of the heels; weak 

 feet, or those in which the horn of the wall is too thin to resist the 

 tendency to spread, wherebj^ the soft tissues are easily lacerated. 

 Wide feet with low heels are always accompanied with a flat sole 

 whose posterior wings either rest upon the ground or the shoe, and 

 as a consequence are easily bruised ; at the same time the arch of the 

 sole is so broad and flat that it can not support the weight of tlie 

 body, and in the displacement which happens when the foot is lested 

 upon the ground the soft tissues are liable to become bruised or torn. 



It is universally conceded that shoeing, either as a direct or predis- 

 posing cause, is most prolific in producing corns. One of the most 

 serious as well as the most common of the errors in shoeing is to be 

 found in the preparation of the foot. Instead of seeking to maintain 

 the integrity of the arch, the first thing done is to weaken it by freely 

 paring away the sole; nor does the mutilation end here, for the frog, 

 which is nature's main support to the branches of the sole and the 

 heels, is also largely cut away. This not only permits of an excessive 

 downward movement of the contents of the horny box, but it at the 

 same time removes the one great means by which concussion of the 

 foot is destroyed. As adjuncts to the foregoing errors must be added 

 the faults of construction in the shoe and in the way it is adjusted 

 to the foot. An excess of concavity in the shoe, extending it too far 

 back on the heels, high calks, thin heels which permit the shoe to 

 spring, short heels with a calk set under the foot, and a shoo too 

 light for the animal w^earing it or for the work required of him, are 

 all to be avoided as causes of corns. A shoe so set so as to press upon 

 the sole or one that has been on so long that the hoof has overgrown 

 it until the heels rest upon the sole and bars becomes a direct cause 

 of corns. Indirectly the shoe becomes the cause of corns when small 

 stones, hard, dry earth, or other objects collect between the sole and 

 shoe. Lastly, a rapid gait and excessive knee action, especially on 

 hard roads, predispose to this disease of the feet. 



Symptoms. — Ordinarily a corn induces sufficient pain to cause 

 lameness. It may be intense, as seen in suppurative com, or it may 

 be but a slight soreness, such as that which accompanies dry corn. 

 It is by no means unusual in chronic corns to see old horses appar- 

 ently so accustomed to the slight pain which they suffer as not to 

 limp at all. But they are generally very restless. They j^aw their 

 bedding behind them at night and often refuse to lie down for a long 

 rest. The lameness of this disease, however, can hardly be said to be 

 characteristic, for the reason that it varies so greatly in intensity ; but 

 the j:)osition of the leg while the patient is at rest is generally the same 

 in all cases. The foot is so advanced that it is relieved of all weight, 

 and the fetlock is flexed until all pressure by the contents of the hoof 



