162 



WINTER SHOEING. 



in England. The wedge shape (fig. 120) is the mosfc popular, 

 as it gives a good foothold and at the same time wears well : 



I'lG. 120. 



KIG. 121. 



Fig. 122. 



Fig. 123. 



Fig. 124. 



the modified wedge with concave faces (fig. 121), though per- 

 haps criving a rather better hold, is not so durable, while the 

 diamond-pointed screw (fig. 123) soon loses its sharp- 

 ness, wears rapidly, and has the grave drawback when 

 new of inflicting dangerous wounds on tlie coronet 

 should the horse cross his legs or slip. For these 

 reasons it is now little used. The square-headed screw 

 (fig. 124) is called a ' blank,' and is used for preserving 

 the holes during ordinary work. It also gives a certain 

 amount of foothold, and is sometimes used even during 

 ¥iQ^.— frosty weather. The screw tap shown is preferable to 

 .Taper tap. ^^^ ordinary form, as the increased size of the head 

 gives greater leverage in screwing, and renders the tap less 

 liable to break at this point. Fig. 126 shows a plug tap for 



clearing the screw holes before in- 

 serting the screw, combining with 

 the tap a ' picker,' useful for clear- 

 ing the holes and removing hard 

 masses of snow, etc., from the foot. 



Modified forms of Screws. — The 

 fact that in large towns, where snow 

 is removed from the streets and the 

 screws come in direct contact with 

 hard pavement, all chisel or pyra- 

 midal screws soon become blunt, renders shoeing both more 

 costly and more troublesome. Attempts have therefore been 

 made to produce screws which remain permanently sharp and 

 prevent slipping even after long wear on hard ground. Such, 

 certainly, have advantages. 



Fig. 126. 



