HORSESHOEING. 



53 



ward or inward bendiugs) are to be regarded as faults or 

 defects. 



The tliichness of the wall is also varial>le. In front lioofs 

 the wall is thickest at the toe, 

 and becomes gradually thinner '^'' 



towards the quarters, while in 

 hind hoofs, there is very little 

 difference in the thickness of 

 the wall of the toe, sides, and C- 

 qnarters. The more slanting 

 half of the hoof is always the 

 thiclcer; thus, for example, the 

 outer wall of a base-^Hde foot 

 is always longer and more 

 oblique than the inner wall^ 

 and is also thicker. According to Mayer, the thickness of the 

 wall at the toe varies from three- to five-eighths of an inch, and 

 at the quarters from 

 two to three eighths 

 of an inch. These 

 measurements are de- 

 pendent upon the 

 size and breeding of 

 the horse. 



The horn wall is 

 composed of three 

 superposed layers. 

 These from without 

 to within are: (1) 

 the periople, secreted 

 by tlie perioplic band. 

 It is very thin, 

 glistening, and varnish-like in appearance, and covers the 

 entire outer surface of the wall, except where it has been 

 removed by the rasp, and prevents rapid evaporation of 



A hoof in profile; a, toe (one half); 6, side 

 wall; c, quarter. 



Fig. 34. 



Vertical section through the middle of a hoof, with horny 

 frog removed, to show the position of the bar: a, b, marks 

 the line at which the wall bends forward and inward to- 

 wards the median line of the foot to become the bar. Bar 

 runs forward and passes imperceptibly into the sole c; o, a', 

 the light shading shows the part of the bar that was in con- 

 tact with the horny frog. 



