114 



HORSESHOEING. 



Fig. 99. 



Fig. 100. 



Outer and inner heel-calks, sharp- 

 ened. 



Fig. 101. 



vertical plane as the outer edge. If a calk is narrow from its 

 base to its end, and at the same time without flaw, it does not 



need a sharp cutting edge. The inner 

 calk should never be sharpened ex- 

 cept the ground be very slippery. 

 The cutting edge of this inner calk 

 stands at right angles to the length 

 of the branch, and its outer corner 

 should then be rounded to prevent 

 its injuring the opposite foot (Fig. 

 100). 



For horses used for heavy draught 

 purposes a toe-calk is welded to the shoe and sharpened. For 

 this purpose we use only steel (toe-steel), which 

 is easily welded to the shoe and remains firm. 

 Toe-calks and steeled heel-calks are tempered, 

 in order, as much as possible, to lengthen their 

 period of durability. This method of sharpening 

 is the oldest and most wide-spread, and is em- 

 ployed on the shoes of all horses of which we 

 require more than light service. 



Hoofs are easily damaged or even ruined by 

 frequently repeated sharpening of the shoes, be- 

 cause every time this is done the shoes must b( 

 removed and replaced. 



3. Shoeing with Screw Heel-Calks. — ^Any or- 

 dinary flat shoe not too thin and narrow at the 

 ends of the branches can be changed to a shoe 

 with screw heel-calks by punching holes in the 

 ends of the branches and cutting a thread in 

 them. 



The screw heel-calk holes are made either by 

 punching or boring. The punching is done by 

 means of an almost cylindrical hammer-punch, afterwards finish- 

 ing the holes by driving through them a round punch which tapers 



Ground-surface of 

 the end of a branch 

 of shoe, showing 

 (a) hole and coun- 

 ter-sinking for o. 

 screw-calk (one- 

 half natural size). 



