HOEN TUBES. 83 



would be very liable to cut and lacerate the limbs upon tlieir 

 inner surfaces. The outer half of the hoof differs also from 

 the inner in another respect : it contains a greater thickness 

 of horn. The importance of knowing this, and other peculiarities 

 of structure shortly to be described, will readily be perceived 

 by the reader, should he peruse the articles on Sandcrack, Ealse 

 Quarter, and other diseases to which the horny substance is 

 liable. 



HoEiS" Tubes. — Those ignorant of the structure of the hoof 

 would naturally suppose it to be a solid mass of horn; an 

 examination of it, however, with a common magnifying lens will 



'f ,-ir-n-== *Yfg^^ ! H T7n y^ Transverse Section of the 



hoof magnified six diameters. 



aaa The Horny Laminse of 

 the Hoof. 



U Tlie Horn Tubes, of 

 wMch the Hoof in mainly 

 ^ composed. 



J%. 9. 



at once prove the incorrectness of this idea. If the reader will 

 procure the hoof of a dead horse,* and look carefully at the 

 coronary concavity, (see Fig. 8, letter 5,) he will notice an 

 immense number of minute pores or openings. These are the 

 commencement of the horn tubes, which are continued from 

 the top to the bottom of the hoof; the hoof in fact is a series 

 of minute cylinders or hollow tubes. These tubes exist in 

 immense numbers, are placed side by side, and traverse the 

 entire length, or rather depth of the horny mass. The animal, 



* This may he readily done hy macerating the limb for some time in water, 

 when the hoof by a little force will easily separate fi'om its connecting tissues, 

 and reveal its tubular structure. 



