298 THE FOOT. 



these arches will shorten and widen, in order to admit of the expansion of the quar- 

 ters — the bow returning to its natural curve, and powerfully assisting the foot in 

 regaining its usual form. It can also be conceived that these bars must form a power- 

 ful protection against the contraction, or wiring in, of the quarters. A moment's 

 inspection of the cut {g, p. 295) will show that, if the bars are taken away, there will 

 be nothing to resist the contraction or falling in of the quarters, when the foot is 

 exposed to any disease, or bad management, that would induce it to contract. One 

 moment's observation of them will also render evident the security which tliey aflbrd 

 to the frog (/), and the effectual protection which they give to the lateral portions of 

 the foot. 



Then appears the necessity of passing lightly over them, and leaving prominent, 

 when the foot is pared for shoeing, that which so many smitlis cut perfectly aw ay. 

 They imagine that it gives a more open appearance to the foot of the horse. Horses 

 shod for the purpose of sale, have usually the bars removed with this view ; and the 

 smiths in the neighbourhood of the metropolis and large towns, shoeing for dealers, 

 too often habitually pursue, with regard to all their customers, the injurious practice 

 of removing the bars. The horny frog, deprived of its guard, will speedily contract, 

 and become elevated and thrushy ; and the whole of the heel, having lost the pow er 

 of resilience or reaction which the curve between the bar c and the crust d gave it 

 (vide p. 295, cut), will speedily fall in. 



THE HORNY LAMINA. 



The inside of the crust is covered by thin horny leaves (c, p. 295), extending al 

 round it, and reaching from the coronary ring to the toe. They are about 500 in num- 

 ber, broadest at their base, and terminating in the most delicate expansion of horn. 

 They not a little resemble tlie inner surface of a mushroom. In front, thej' run in a 

 direction from the coronet to the toe, and towards the quarters they are more slanting 

 from behind forwards. They correspond, as will be presently shown, with similar 

 cartilaginous and fleshy leaves on the surface of the coffin-bone, and form a beautiful 

 elastic body, by which the whole weight of the horse is supported. 



THE SOLE 



Is under, and occupies the greater portion of the concave and elastic surface of the 

 foot (see h, p. 295), extending from the crust to the bars and frog. It is not so thick 

 as the crust, because, notwithstanding its situation, it does not support so much 

 weight as the crust; and because it was intended to expand, in order to prevent con- 

 cussion, when, by the descent of the bone of the foot, the weight was thrown upon it. 

 It is not so brittle as the crust, and it is more elastic than it. It is thickest at the toe 

 (see /, p. 272), because the first and principal stress is thrown on that part. The 

 coffin-bone, /, ia driven forward and downward in that direction. It is likewise 

 thicker where it unites with the crust than it is towards the centre, for a similar and 

 evident reason, because there the weight is first and principally thrown. 



In a state of nature it is, to a certain degree, hollow. The reason of this is plain. 

 It is intended to descend or yield with the weight of the horse, and by that gradual 

 descent or yielding, most materially lessen the shock which would result from the 

 sudden action of the weight of the animal in rapid and violent exercise ; and this 

 descent can only he given by a hollow sole. A flat sole, already pressing upon the 

 ground, could not he larought lower ; nor could the functions of the frog be then dis- 

 charged ; nor woidd the foot have so secure a hold. Then if the sole is naturally 

 hollow, and hollow because it must descend, the smith should not interfere with this 

 important action. When the foot will bear it, he must pare out sufficient of the horn 

 to preserve tlie proper concavity ; also a small portion at the toe and near the crust, and 

 cutting deeper towards the centre. He must put on a shoe which shall not prevent 

 the descent of the sole, and which not only shall not press upon it, but shall leave 

 sufficient room between it and the sole to admit of this descent. If the sole is pressed 

 upon by the colfin-bone during the lengthening of the elastic ]amina% and the shot 

 will not permit its descent, the sensible part between the coffin-l)one and the liorn wil 

 necessarily be bruised, and inflammation and lameness will ensue. It is from this 

 cause, that if a stone insinuates itself between the shoe and the sole, it produces so 

 much lameness. Of the too great concavity of the sole, or the want tf cor.cavity in 

 it, we shall treat when we arrive at diseases of the foot. 



