THE FROG. 299 



THE FROG. 



In the space between the bars, and accurately filling it, is the frog. It is a trian- 

 gular portion of horn, projecting from the sole, almost on a level with the crust and 

 covering and defending a soft and elastic substance called the sensible frog. It is 

 wide at the heels, and there extending beyond a portion of the crust ; narrowing 

 rapidly when it begins to be confined between the bars, and terminating in a point at 

 somewhat more than half the distance from the heel to the toe. It consists of two 

 rounded or projecting surfaces, with a fissure or cleft between them, reaching half- 

 way down the frog, and the two portions again uniting to form the point or toe of the 

 frog. 



The frog is firmly united to the sole, but it is perfectly distinct from it. It is of a 

 different nature, being softer, and far more elastic ; and it is secreted from a different 

 surface, for it is thrown out from the substance which it covers. It very much 

 resembles a wedge, with the sharp point forwards; and it is placed towards the bade 

 part of the foot. The foot is seldom put flush and flat upon the ground, but in a 

 direction downwards, yet somewhat forwards ; then the frog evidently gives safety to 

 the tread of the animal, for it occasionally ploughs itself into the ground, and pre- 

 vents the horse from slipping. This is of considerable consequence, when some of 

 the paces of the horse are recollected, in which his heels evidently come first to the 

 ground, and in which the danger from slipping would be very great. Reference needs 

 only be made to the gallop, as illustrative of this. 



The frog being placed at, and filling the hinder part of the foot, discharges a por- 

 tion of the duty sustained by the crust ; for it supports the weight of the animal. It 

 assists, likewise, and that to a material degree, in the expansion of the foot. It is 

 formed internally of two prominences on the sides (see a, p. 295), and a cleft in the 

 centre, presenting two concavities with a sharp projection in the middle, and a gradu- 

 ally rounded one on each side. It is also composed of a substance peculiarly flexible 

 and elastic. What can be so well adapted for the expansion of the foot, when a por- 

 tion of the weight of tlie body is thrown on itT How easily will these irregular sur- 

 faces yield and spread out, and how readily return again to their natural state ! In 

 this view, therefore, the horny frog is a powerful agent in opening the foot ; and the 

 diminution of the substance of the frog, and its elevation above the ground, are both 

 the cause and the consequence of contraction — the cause, as being able no longer 

 powerfully to act in expanding the heels ; and the consequence, as obeying a law of 

 nature, by which that which no longer discharges its natural function is gradually 

 removed. It is, however, the cover and defence of the internal and sensible frog, 

 which will be presently treated of; enough, however, has been said to show the 

 absurdity of the common practice of unsparingly cutting it away. In order to dis- 

 charge, in any degree, some of the offices which we have assigned to it, and fully to 

 discharge even one of them, it must come in occasional contact with the ground. In 

 the unshod horse, it is constantly so : but the additional support given by the shoes, 

 and more especially the hard roads over which the horse is now compelled to travel, 

 render this complete exposure of the frog to the ground not only unnecessary, but 

 injurious. Being of so much softer consistence than the rest of the foot, it would be 

 speedily worn away : occasional pressure, however, or contact with the ground, it 

 must have. 



The rough and detached parts should be cut off at each shoeing, and the substance 

 of the frog itself, so as to bring it just above or within the level of the shoe. It will 

 then, in the descent of the sole, when the weight of the horse is thrown upon it in 

 the putting down of the foot, descend likewise, and pressing upon the ground, do Us 

 duty; while it will be defended from the wear, and bruise, and injury that it would 

 receive if it came upon the ground with the first and full shock of the weight. This 

 will be the proper guide to the smith in shoeing, and to the proprietor in the direc- 

 tion which he gives. The latter should often look to this, for it is a point of very 

 great moment. A few smiths carry the notion of frng pressure to an absurd extent, 

 and leave the frog beyond the level of the sole, — a practice which is dangerous in 

 the horse of slow draught, and destructive to the hackney or the hunter; but the 

 majority of them err in a contrary way, and, cutting off too much of the frog, lift it 

 above the ground, and destroy its principal use. It should be left just above, or within 

 the level of the shoe. 



