AND HOW TO KEEP IT SOUXD. 17 



layer of horn that covers the frog is thinnei in substance 

 and more delicate in texture than that of any other part of 

 the foot, and, when once destroyed, is very imperfectly and 

 sparingly reproduced. The first stroke of the knife removes 

 this thin liorny covering altogether, and lays bare an under 

 surface, totally unfitted, from its moist, soft texture, for ex- 

 posure either to the hard ground or the action of the air ; 

 and in consequence of such unnatural exposure it soon 

 becomes dry and shrinks : then follow cracks, — the edges 

 of which turning outwards form rags ; these rags are re- 

 moved by the smith at the next shoeing, whereby another 

 such surface is exposed, and another foundation laid for 

 other rags ; and so on, until at last the protruding, plump, 

 elastic cushion, interposed by nature between the navicular 

 joint and the ground, and so essential to its preservation from 

 injury, is converted by the mischievous interference of art 

 into the dry, shrunk, unyielding apology for a frog, to be 

 seen in the foot of almost every horse that has been regu- 

 larly shod for a few years. The frog is provided within 

 itself with tvv^o very efficient modes of throwing off any 

 superfluous horn it may be troubled with ; and it is very un- 

 wise in man to interfere with them : the first and most com- 

 mon is the separation from its surface of small bran-like 

 scales, which becoming dry fall off in a kind of whitish 

 scurf, not unlike the dust that adheres to Turkey figs. The 

 other, which is upon a larger scale, and of rarer occurrence, 

 is sometimes called " casting the frog." A thick layer of 

 frog separates itself in a body, and shells off — to the full as 

 deep as a usual paring with the knife : but it is worthy of 

 remark, that there is this very important difference between 

 the two operations : nature never removes the horny cover- 

 ing until she has provided another horny covering beneath, 

 so that although a large portion of the frog may have been 

 removed, there still remains a perfect frog behind, smaller it 

 is true, but covered with horn and in every way fitted to 

 sustain exposure ; while the knife, on the contrary, removes 

 the horny covering, but is unable to substitute any other 

 in its stead. My advice therefore is to leave the frog to 

 itself — nature will remove the superfluous horn, and the 

 rags can do no harm, and, if unmolested, will soon disappear 

 altogether. 



In describing the form of the shoe, and explaining its 



■details, I shall not hesitate to repeat any thing which I may 



have said before^ if it should appear to me that by so doing 1 



2* 



