2 26 MANUAL OF MODERN FARRIERY 



When hollow at the quarter, it is a clear indication 

 of contraction to a considerable extent. 



The perspective representation which we have 

 given, Plate vi, fig. ii, will convey a clear idea of 

 the structure of the crust and its various component 

 parts. 



a. The coronary ring, which is a circular, attenuated, con- 



cavo-convex part, entering into the composition of the 

 coronet. Its extent is marked exteriorly by the whitish 

 aspect which it assumes, and likewise by a partial 

 separation and eversion of the outer flakes of horn 

 around its junction with the wall, or crust below. 



b. The small horny plates which line the crust. These 



consist of numerous narrow laminae, or processes, 

 arranged with the nicest order and mathematical pre- 

 cision upon the internal surface of the wall. They 

 extend in uniform parallels in a perpendicular direction 

 from the lower edge of the superior border to the line 

 of junction of the wall with the sole, and are so thickly 

 set, that no part of the superficies remains unoccupied 

 by them. They are also continued upon the surfaces 

 of the bars. They are soft, yielding, and elastic ; but 

 from exposure they become dry and rigid. Every 

 plate exhibits two edges and two surfaces. By one 

 edge it grows to the wall, and the other, which is 

 somewhat thinned, hangs loose and floating within the 

 cavity of the hoof. These are two smooth lateral 

 surfaces, and, considering the magnitude of the lamella 

 itself, of enormous extent ; so much so, that it may be 

 said almost to be constituted entirely of superficies. 

 Looking at this, we are naturally led to the contempla- 

 tion of the great and magnificent designs which Nature 

 evidently had in view in their formation and beautiful 

 adaptation, viz., the production of ample surface within 

 a small space, an end that has been obtained through 

 the means of multiplication. A mathematical calcula- 

 tion was made by the late Thomas Evans, LL.D., of 

 what the united superficies of these lamellae amounted 

 to, and it was found that they afforded an increase of 

 actual surface more than the single internal area of the 



