THE SOLE. 375 



the inside of the bars, like the inside of the crust see the first and larger cut 

 presents a continuance of the horny leaves, showing that it is a part of the same 

 substance, and helping to discharge the same office. 



It needs only the slightest consideration of the cut, or of the natural hoof, to 

 show the importance of the bars. The arch which these form on either side 

 between the frog and the quarters, is admirably contrived both to admit of and 

 to limit to its proper extent the expansion of the foot. When the foot is placed 

 on the ground, and the weight of the animal is thrown on the leaves of which 

 mention has just been made, these arches will shorten and widen, in order to 

 admit of the expansion of the quarters 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 powerful protection against the 

 contraction, or wiring in, of the quarters. A moment's inspection of the cut (see 

 </, page 372) 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 they 

 afford 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 pro- 

 minent, when the foot is pared for shoeing, that which so many smiths cut 

 perfectly away. 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 power of resilience or 

 reaction which the curve between the bar c and the crust d gave it (vide p 372, 

 cut), will speedily fall in. 



THE HORNY LAMINA. 



The inside of the crust is covered by thin horny leaves (c, page 372), ex- 

 tending all round it, and reaching from the coronary ring to the toe. They are 

 about 500 in number, broadest at their base, and terminating in the most 

 delicate expansion of horn. They not a little resemble the inner surface of a 

 mushroom. In front they run in a direction from the coronet to the toe, and 

 towards the quarters they are more slanting from behind forwards. They cor- 

 respond, 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 &, page 372), 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 concussion, 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 tf, page 346), because the first 

 and principal stress is thrown on that part. The coffin-bone/is driven for- 

 ward 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. 



