398 CORNS. 



quarters, although we may be able to ascertain by the use of the probe that the 



separation of the crust extends for a considerable space above the sole. 



CORNS. 



In the angle between the bars (c, p. 374) and the quarters, the hom of the sole 

 has sometimes a red appearance, and is more spongy and softer then at any other ■ 

 part. The horse flinches when this portion of the horn is pressed upon, and 

 occasional or permanent lameness is produced. This disease of the foot is. 

 termed corns : bearing this resemblance to the corn of the human being, that 

 it is produced by pressure, and is a cause of lameness. When corns are 

 neglected, so much inflammation is produced in that part of the sensible sole, 

 that suppuration follows, and to that, quittor succeeds, and the matter either un- 

 dermines the horny sole, or is discharged at the coronet. 



The pressure hereby produced manifests itself in various ways. When the 

 foot becomes contracted, the part of the sole inclosed between the external crust 

 that is wiring in, and the bars that are opposing that contraction (see cut, p. 

 374), is placed in a kind of vice, and becomes inflamed ; hence it is rare to see 

 a contracted foot without corns. When the shoe is suffered to remain on too 

 long, it becomes imbedded in the heel of the foot ; the external crust grows 

 down on the outside of it, and the bearing is thrown on this angular portion of ' 

 the sole. No part of the sole can bear continued pressure, and inflammation 

 and corns are the result. From the length of wear the shoe sometimes becomes 

 loosened at the heels, and gravel insinuates itself between the shoe and the 

 crust, and accumulates in this angle, and sometimes seriously wounds it. 



The bars are too frequently cut away, and then the heel of the shoe must be 

 bevelled inward, in order to answer to this absurd and injurious shaping of the 

 foot. By this slanting direction of the heel of the shoe inward, an unnatural 

 disposition to contraction is given, and the sole must suffer in two ways, — in 

 being pressed upon by the shoe, and squeezed between the outer crust and the 

 external portion of the bar. The shoe is often made unnecessarily narrow at 

 the heels, by which this angle, seemingly less disposed to bear pressure than any 

 other part of the foot, is exposed to accidental bruises. If, in the paring out of ' 

 the foot, the smith should leave the bars prominent, he too frequently neglects 

 to pare away the hom in the angle between the bars and the external crust ; or 

 if he cuts away the bars, he scarcely touches the horn at this point ; and thus, 

 before the horse has been shod a fortnight, the shoe rests on this angle, and pro- 

 duces corns. The use of a shoe for the fore feet, thickened at the heels, is, and 

 especially in weak feet, a source of corns, from the undue bearing there is on 

 the heels, and the concussion to which they are subject. 



The unshod colt rarely has corns. The heels have their natural power of 

 expansion, and the sensible sole at this part can scarcely be imprisoned, while 

 the projection of the heel of the crust and the bar is a sufficient defence from 

 external injury. Corns seem to be the almost inevitable consequence of shoe- 

 ing, which, by limiting, or in a manner destroying, the expansibility of the foot, 

 must, when the sole attempts to descend, or the coffin-bone has a backward and 

 downward direction (see cut, p. 345), imprison and injure this portion of the 

 sole. This evil consequence is increased when the shoe is badly formed, or 

 kept on too long, or when the paring is omitted or injudiciously extended to the 

 bars. By this unnatural pressure of the sole, blood is thrown out, and enters 

 into the pores of the soft and diseased horn which is then secreted ; therefore the 

 existence and the extent of the corn is judged of by the colour and softness of 

 the hom at this place. 



Corns are most frequent and serious in horses with thin horn and flat soles, 

 and low weak heels. They do not often occur in the outside heel. It is of a 



