4 NOTES ON SHOEING OF HORSES. 



The crust, at best, is very thin, in comparison 

 with the great weight of 12 to 15 cwt., which it 

 has to sustain. It is very easy, therefore, to con- 

 ceive how important it must be to preserve it whole 

 and uninjured, and to understand how much harm 

 results from even a little thinning or rasping. 



It is true that the crust is constantly growing 

 down from the coronet, but to form an entirely 

 new crust requires six or seven months, during 

 which period, under the ordinary system of shoeing, 

 it may have been rasped some six or seven times, 

 whilst the lower part, on which the shoe imme- 

 diately rests, and into which the nails are driven, 

 having been longest in growing, will also have been 

 rasped the most. 



But the mere diminution of the thickness of the 

 crust, though in itself undoubtedly a serious evil, 

 represents but a very small portion of the mischief 

 caused by rasping. This will become more apparent 

 when the structure of the crust is understood. 



stnicture 6. The crust, or outer wall of the foot, is secreted 

 ecrus . 1^^ ^j^^ protuberant band of thickened vascular skin, 

 extending for about a finger's breadth above the 

 hoof, and grows down from it in longitudinal fibres. 

 The secreting substance is called the coronary band. 

 The crust is attached to the interior of the foot 

 by the sensitive and insensitive laminae, which dove- 

 tail into each other. 



