104 AMERICAN FARMER'S HORS:^ BOOK. • 



eased matter all around the top of the foot, through the 

 coronary ring. Contraction of the hoof, or narrow heel, is 

 usually the result of caries, or decay of the bones of this 

 joint, the back portions of the hoof dropping in together. 

 Thrush is but the beginning of foot evil, the purulent mat- 

 ter collected at the joint escaping through the heel and frog 

 of the foot. Greasy heel is a case of enlarged thrush, and 

 often from the same causes. Tloof rot, or pummiced feet, 

 often accompany navicular disease. Cracked hoof, or sand 

 cracks, proceed from brittle hoofs, which this ailment produces. 

 It must be understood that these diseases may have an 

 origin independent of that which we are now considering; 

 but in a majority of cases they are found in connection with 

 this joint disease, and in a large number of instances are 

 produced by it. 



CRACKED HOOFS. 



This is otherwise called sand cracks, from the prevalent 

 opinion that such cracks occur in sandy regions much oft- 

 en er than elsewhere. Such is not the case, however. This 

 belief has obtained from the fact that these cracks are lia- 

 ble to become filled with sand, when they are always very 

 troublesome. Of course, where there is no sand this cir- 

 cumstance does not happen. Cases of this kind are com- 

 paratively rare in this country, so much so, indeed, as 

 scarcely to call for any mention here. 



Cracked hoof is consequent upon a long-standing diseased 

 and feverish condition of the feet, from which causes the 

 hoof becomes hard, dry, and brittle, until, at length, it splits 

 open. The elasticity and toughness of the healthy hoof are 

 gone. Harrow heel is another cause of cracking, when fever 

 has made the hoof hard and dry. The back of the heel drops 

 in, which naturally occasions cracking in front. Hoof-rot 

 produces the same efiect. The decay of the bottom of the 

 feet is sometimes very great, leaving but a mere shell of the 

 hoof, the sides of which have become very thin and brittle. 

 When the horse has been kept shod for a long time, and the 



