DISEASES OF THE H0K3E. o'J5 



always appear m the sole in the angle between the bar and the outside 

 wall of the hoof. In many cases the lamina? of the bar, of the wall, 

 or of both, are involv^ed at the same time. 



Three kinds of corns arc commonly recog-nized — the dry, the moist, 

 and the suppurative — a division based solely on the character of the 

 conditions which follow the primary injury. 



The fore feet are almost exclusively the subjects of the disease, for 

 two reasons: First, because they support a greater part of the body; 

 secondly, because the heel of the fore foot during progression is first 

 placed upon the ground, whereby it receives much more concussion 

 than the heel of the hind foot, in which the toe first strikes the 

 ground. 



Causes. — It may be said that all feet are exposed to corns, and that 

 even the best feet may suifer from them when conditions necessary to 

 the production of the peculiar injury are present. The heavier breeds 

 of horses generally used for heavy work on rough roads and streets 

 seem to be most liable to this trouble. Mules rarely have corns. 



Among the causes and conditions which predispose to corns may be 

 named high heels, which change the natural relative position of the 

 bones of the foot and thereby increase the concussion to which these 

 parts are subject; contracted heels, which in part destroy the elas- 

 ticit}^ of the foot, increase the pressure upon the soft tissues of the 

 heel, and render lacerations more easy; long feet, which b}' removing 

 the frog and heels too far from the ground deprive them of necessary 

 moisture, which, in turn, reduces the elastic properties of the horn and 

 diminishes the transverse diameter of the heels; and weak feet, or 

 those in which the horn of the wall is too thin to resist the tendency 

 to spread, whereby the soft tissues are easily lacerated. Wide feet 

 with low heels are alwaj^s accompanied b}" a flat sole whose posterior 

 wings either rest upon the ground or the shoe, and as a consequence 

 are easil}' In-uised; at the same time the arch of the sole is so broad 

 and flat that it can not support the weight of the body, and in the dis- 

 placement w^hich happens when the foot is rested upon the ground the 

 soft tissues are liable to become bruised or torn. 



It is universall}^ 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 f)reparation of the foot. Instead of seeking to maintain 

 the integrit}' of the arch, the first thing done is to weaken it by freely 

 paring awa}" 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 horn}^ 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 



