A series of original experiments on the foot of the living horse, exhibiting the changes produced by shoeing, and the causes of the apparent mystery of this art / By Bracy Clark.

  • Clark, Bracy, 1771-1860.
Date:
1809
Catalogue details

Licence: Public Domain Mark

Credit: A series of original experiments on the foot of the living horse, exhibiting the changes produced by shoeing, and the causes of the apparent mystery of this art / By Bracy Clark. Source: Wellcome Collection.

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    so large a surface, or divided into so many points, that it cannot be severely felt by any of them ; and least of all, those parts that last expe- rience it, or that are the furthest removed from the soil. The bars appear in this case to be acted upon in the manner already described, forcing by their direction the heels outwards, and thus first re- lieve, and prepare a way for the share of operation the frog is to re- ceive : acting then without much compression. Much less does it ap- pear in the view's of Nature, that it should drive out the heels by forcible pressure against them, which would produce first fatigue, and tjhen soreness for these parts to act well, a certain share of liberty is necessary among them, one should apprehend. If we turn our attention to the nature of the frog itself, we find it no other than an inverted hollow arch, of not very hard horn, filled with soft matters within, that appear incapable of great resistance, or of carrying much pressure to the neighbouring parts*, such as might be looked for, for such an effect as forcing the heels, that the horn of the arch must be depended on almost alone for this purpose. Let us also see the manner in which this horn of the frog is connected to the bar by its upper edges, or margin : being the heels or foot of the arch by which the arch seems weakest for any forcible action : and its being also not so strong and hard as the material it has to act against. It appears, in fact, that it is not so much nom the upward pressure against the frog, as from the downward pressure of the limb and weight of the body upon the bones of the foot, that should produce this effect of expansion upon the yielding contents of the hoof and heels ; timely assisted, and in due time prevented, from too much de- * It will probably be urged in opposition to this, that parts, though ever so soft, will resist with the same force as hard ones if confined, which is certainly true, after considerable conden- sation ; and this might happen to the frog; but the hollow cavity on either side of it, of the com- missure, will prevent such a circumstance, as well as the descent of the frog under pressure from above, which ever brings it into a more open space downwards. pression