DETAILS OF SHOEING. 483 



seldom complain that their horses go worse towards the. end of a set of 

 shoes than at the beginning. 



Calkins are an evil, because they interfere with the natural bearing of 

 the foot on the ground ; ; because they deprive the hinder portion of the 

 foot of its fair share of work and pressure ; because they unduly raises 

 the hind quarter and thereby tend to increase the risk of sprain so 

 common in the hock ; because they are a frequent cause of injury from 

 treads and kicks, and because they make both treads and kicks, when 

 they occur, more severe than they would otherwise be. Calkins on the 

 : inside are especially apt to cause injuries from treads. 



If, however, it is thought necessary to use calkins, the better plan is to 

 apply them to the outside heels only, and the heels of the shoe on the 

 inside should be proportionately thickened, so as to give a level bearing 

 to the foot on the ground. * 



,A calkin should be turned up wide (A, fig. 15) and made of steel. If 

 made, as is often the case, narrow or little more than a spike, it soon 

 wears down, and ceases*to be of any use (n, fig. 15). 



Calkins are utterly inadmissible on the fore-feet. (For Calkins on 

 very heavy horses, see 633.) 



987. Shoes to le level. 



A natural and level bearing of the shoe on the foot, and a natural and 

 level tread, are matters of primary importance. All that interferes with 

 such natural and level tread is an evil, except in special cases of disease 

 or malformation!. In a succeeding chapter, No. 65, in regard to the 

 treatment of injuries and disease, frequent reference will be made to the 

 advantages gained by the use of three-quarter shoes or of shoes raised at 

 both heels or at one heel only. But all such deviations from a natural 

 tread are an evil, except in special cases. As soon as the injury or dis- 

 ease ceases to require such artificial bearing, the horse should be again 

 shod level. 



988. Directions to the Farrier for shoeing ordinary Fore-feet. 



1. With your rasp remove from the ground surface of the crust, as 

 much as may represent a month's growth. Remember, that there is 

 usually a more rapid growth of horn at the toe than at the heels or 

 quarters. More, therefore, will require to be taken off the toe than from 

 other parts in other words, shorten the toe. Having lowered the crust 

 to the necessary extent, make the under or ground surface perfectly level 

 with the rasp. 



2. Hound off the lower edge of the crust with the rasp in the manner 

 explained in Par. 947. Do this carefully and thoroughly with the fine 

 side of the rasp. If a sharp edge be left, the crust will be apt to split 

 and chip. 



The preparation of the foot is now complete. It remains to fit the 

 shoe to the foot. 



3. Make a shoe with J-inch web, of even width all round except to- 



