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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    11T ing the ground ; it is also defended laterally below by the bars or in= torsions of the hoof, and by the stratiform processes of the cartilages, but immediately beneath by the softer material of the internal frog*. fn this obscure part it is, in the cases of kennel nailsy—for so they are technically termed, from being picked up by the feet of horses in the streets and ways, and which are attended with such deplorable ef- fects often,—that we are induced to speak of them here; that the ten- don being injured by the nail passing through the frog, a deep- seated abscess forms in this part, if the wound does not quickly heal after the injury : from being ill understood and awkward of access, it is usually permitted to go on till it bursts through the heels or rushes up the limb in the course of the tendon, destroying the horse by its ravages # A very remarkable construction, which does not appear to have been understood, is found with the internal frog, and which we take the opportunity of relating here, as it appears particularly calculated to defend these dangerous parts from suffering under strong pressure or casual irregularities of the ground. The mass of elastic material which fills the upward or inward cavity or arch of the horny frog is exteriorly covered by a frame-work or capsule, of a white, tough, dense ligament; and this capsule, in form like the frog, presents three sides, giving the in- ferior and two lateral surfaces of the frog. Within this ligamentary case or envelop- ment are formed several plates of tendons, which are disposed horizontally and attach to the sides of the capsule, and have between them a very lax, soft, glossy, elastic membrane, also attached by short tendons to the surfaces of the above layers, and which, on the frog being cut perpendicularly through, and being pressed upon, projects from between these layers, and is like the caoutchouc, but of less resistance; and in the na- tural state this elastic membrane appears perfectly white, but assumes with being kept a yellow appearance, and a yellowish semifluid oil then forms about it, which perhaps is the cause of its having been mistaken for actual masses or bags of yellow oil: when seized with the forceps, its membranous nature becomes apparent. These transverse layers of ligament appear to give the foundation or principle to the structure of the internal frog ; and these ligaments or tendons, in approaching the point ®f the frog, converge, and are condensed into a stout tendon, holding this part to the anterior edge of the cavity before mentioned of the coffin-bone. These layers of tendon 2 « or