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In this sentence, by found, the author -eems to mean entire, and to intimate that, when the horny or outer frog is in part removed, what remains is not sufficient to defend the inner or Heshy frog from being bruised.
*Granite and other hard substances' (he obferves)' have no effect' (ill, we suppose, is understood) on the frog, when it is preserved, and the hoof properly shod : but, where it is soft and tender, in confequence of being cut, and raised by a thick heeled shoe, one stroke from a projeâing stone will produce pain, while perpetual presure, with a proper Moe, is attended with falutary effects.' P.
The principle chiefly recommended in this section is, that the frog should be kept as much as possible in contact with the ground, as it will thus become extremely hard, and less liable to be injured than when it is foft, will prevent the heels from contracting, be enabled to perform its other functions to the greatett advantage, and be preserved in its original condition.
In our capacity of reviewers, it is our duty to detect and expose every attempt to bring forward old ideas as new ones ; and, as Mr. Coleman has not acknowledged his obligations in this respect, we deemn it necessary to state, that the substance of this section is to be found in the Cours d'Hippiatrique of La-Fofle, under the article Ferrure. Our author, indeed, has considerably expanded the ideas of the French writer, and las adduced foine ingenious arguments in support of them; but he has not entirely convinced us that this practice, carried to the extent he recommends, is free from defects. - Не affirms, that the external frog is composed of fost elastic horn, and is totally insenlible;' and he makes use of the following argument in defence of original organisation.
6. Any man in the least acquainted with the wisdom of nature will be convinced, that, if the bars had been of no ute, they would not have been created. As they are always found in a natural hoof, the conclusion is felf-evident, that they are of some use.'
This, we think, is sound logic. We therefore heg Mr. Coleman's perinission to employ it here, and to substitute a few other words, which only affect the nature of the fact, without altering the force of the reasoning. Any man in the least acquainted with the wisdom of nature will be convinced, that, if the softuess of the frog were of no usc, the frog would nut have been soft in the state of nature. As it is al, ways found soft in a colt at grass, the conclusion is self-evident that this fofinefs is of some use.'
It is known that hard bodies have the property of transmitting through their fubftance any motion communicated to their surface more readily than fofit ones, and that, the more
denfe is the body, the greater is the velocity of the motion. When machinery of any kind is in regular motion in one difection, and a considerable blow is given to it in a different one, a jar is produced, which renders the motion irregular, and tends to spoil the machinery; and where blows of this kind are apprehended, a soft elastic body is placed to receive them, and, by its spring, to cut off the shock. The foot of the horse is intended to receive a confiant fucceffion of blows; and nature has endeavoured to prevent the bones of the different joints in the legs from being jarred and interrupted in their movements, by placing the frog, a soft and very elastic cushion, to receive the blows and obstruct the propagation of the shocks.
It is a fact that the frog, by bearing against the ground at every step, becomes much harder than it would be if it were only to come against it occasionally : but it is also a fact, that, as it acquires hardness, it loses its yielding quality, which, in our opinion, is essential to the due performance of its functions. It is only by art that the frogʻis inade to come in contact with the ground at every step. If this circumstance had been neceffary, or even the most advantageous for the foot, we may prefume that it would not have been left to the fagacity of man to make the discovery, but rather that the frog would have been originally constructed on such a plan as would have ensured its being conftantly in such a fituation. Now, as we have before obierved, that, in the foot of a colt at grafs, the frog.is much oftener short of, tiran on a level with, ihe heels, we submit it to better phyfiologists than we are, to determine whether. it is not probable that the frog was intended to come in contact with the ground occafionally, rather than at every step. By the continual pressure, its elasticity is diminished; but, by pressure merely occasional, its flexibility is preierved, and comes into use when it is particularly wanted. In flow movements, the proportional weight of the body is thrown upon each limb flowly and without much force, and the hind tendons are able to hear it with perfect safety, without the frog preffing on the ground; but in quick movements, where the weight is thrown with rapidity and great force on the back of the leg, the tendons would be liable to be strained or even ruptured, were they not supported behind and below; and then it is that the frog, being driven against the ground, receives the blow, spreads, and, by its elastic property, breaks the shock.
The joint within the hoof, commonly called the coffinjoint, is formed of three bones; fo connected, as to have conliderable play in the found ftate. To preferve this play, nature appears to have wisely rendered the frog soft and elastic, as the crust and horny fole are made hard and less elastic, to
secure and defend the interior parts of the foot from injury. Indeed, a longitudinal section of the foot shows that the shuttle-bone plays on the surface of the flexor tendon, and forces the sensible frog downward in quick and strong moveinents. Hence it is evident, that hardness in the horny frog, destroying its natural elasticity, muft hinder the descent of the tendoni, and, like an over-tight hoe in the human subject, must cramp and impede the action of the joint, and ultimately produce dilease.
The original softness of the frog is also connected with a function which we must not pafs over in silence: a fiuid of a peculiar smell is thrown out by the frog; and, when this has long remained in contact with its furface, it becomes putrid, diffolves the parts where it accumulates most. (as in the side fiffures), constituting what is called a thrush, and, if neglected, degenerates into canker. Upon the fame principle, the cuticle, between the toes of men who are uncleanly in their perfons, is diffolved.
We agree with Mr. Coleman in condemning, for general wsc, high-heeled shoes, which almost entirely prevent the frog from coming in contact with the ground, as they tend to produce difeases in that part. On the other hand, it is reasonable to suppose, that the continual pressure of the frog on the ground, by hardening its surface, will considerably impede the due secretion and escape of its perspirable matter. In support of this reasoning, we may remark, that many horses, which have had their frogs hardened by long-continued pressure on the ground, and have been much used, frequently shift the weight of the body, when standing in the stable, from one fore-foot to the other, as if uneasy, although there may be no other indication of disease than the leat and dryness of the feet. Such horses, when taken out of the stable, are more disposed to canter than to trot, because in cantering they use the hind parts more than in trotting, and thus relieve their fore-feet. To moisten the lower part of the feet, tends to a removal of the symptoms of uneasiness, and more especially, if the hard surface of the frog be pared a little, and kept from constantly pressing on the ground. The cut surfaces of such frogs have frequently been found speckled with a great number of small red points of coagulated blood.
The frog is certainly less liable, when it is hard, to be cut Dy flints or other sharp substances, than when it is foft:.but accidents of this nature occur so rarely, that the advantage óbitained in this refpect will by no means over-balance the inconveniencies which conftantly accompany its hardness: and although the contact of the frog with the ground at every ftep may tend to prevent contractions in the heels, yet we are of
opinion, that this end may be attained by less objectionable means.
Upon the whole, we are disposed to maintain, that to render the horny frog hard, is to counteract the original intention of nature, as, the harder it becomes, the more the action of the coffin-joint is restrained, the frog is the less capable of spreading, or of adapting itself to the surface on which it falls, its spring is the more diminished, and it is the more calculated to transmit shocks to the parts which are above it.
The second fection relates to the common practice of shoeing horses, and its confequences.' In this part of the work, the writer charges farriers with greater abufes than they really commit, without considering that he thus injures the cause wliich he wishes to serve, and raises doubts in the minds of his readers with regard to the general authenticity of his statements.
. Before any fioe be fitted to the hoof, the bars are totally, and the frog partly, removed by an instrument called the butteris. If it be true, that the bars are made to prevent the heels from contraction, or, indeed, if the bars have any function, that function must be loft when they are destroyed.'
P. 40. The practice of cutting away much of the lower part of the hoof is still too general, though it has been decried by all the writers who have treated of thoeing for some years past; and we agree with our author that mischief is produced by it.
• The bars, or binders, as they are termed, are two in number. They are placed between the frog and fole; and, at the heels, form a broad solid junction with the crust.' The toe, or small part of the bar, sometimes reaches externally nearly as far as the toe of the frog. The bars within the hoof are laminated in the faine manner as the internal part of the crust, and are attached to the horny sole. The insensible laminæ are intimately connected with the laminæ of the fenfible sole.'
P. 27. Farriers are certainly too much in the habit of scooping or hollowing the external part of the bars; but they never cut them away totally, as, if they should do so, the sentible fole above would become bare, and the horse would immediately he larned. This we understand to be the fact; and, if only part of the bars be removed, the author's conclusion respecting the destruction of their functions can only be crue in part.
• The removal of the bars is termed, opening the heels; and is performed for the express purpose, that the heeis may not contract, or the heels of cbe Mhoe press upon the role, and occasion corns. But it is rather unfortunate, that this operation, intended to prevent
coins, and contracted heels, fhould be the remote cause of the very diseases designed to be obviated.' P. 41.
Here Mr. Coleman feems to have had in view the following passage of M, Soleysel, who wrote on this subject in 1744.-. On appelle ouvrir les talons, lorsque le maréfchal en parant le pied coupe le talon près de la fourchette, et l'emporte jusqu'au haut à un doigt de la couronne, enforte qu'il sépare les quartiers du talon, et par ce moyen il affame le pied et le fait ferrer : ce qu'ils appellent ouvrir un talon, est proprement le faire ferrer, Parfait Maréschal, seconde partie.
The function of the frog, as a stop, must be injured by the removal of a considerable portion of it; and we think that it will seldom be found necessary to take away any more than the ragged parts.
As the craft is always lowered before the shoe is put on, and the sole generally thinned, we naturally expected that the author would have touched upon this part of the process of preparing the hoof for the Phoe, as well as that which relates to the bars and the frog; and we are the more disappointed in this respect, as we are of opinion, that to hollow the fole leads to confequences nearly as injurious to the safety of the parts within the hoof, as the practice fo strongly reprobated by Mr, Coleman. From his filence on this head, we conclude, either that the laţter circumstance has escaped his notice, which we can scarcely suppose, or that he approves the practice, which we have as much difficulty in believing. Whatever may bave been the cause of the omiffion, the description of the usual mode of preparation is rendered imperfect by it.
We have proceeded to greater length in the examination of this subject than we at first intended; but we conceive the public to be interested in every thing which relates to the prefervation of so useful an animal as the horse.
The Study and Practice of the Law considered, in their va
rious Relations to Society. In a Series of Letters. By a Member of Lincoln's Inn. 8vo. 6s. Boards. Cadell and Davies. 1798.
THE study of the law is obvioufly a subject of great importance; and various productions have appeared, in which the authors have professed to point out the most eligible mode of directing the attention of the student. It may, however, be remarked of thofe publications, that in many instances they merely repeat the advice attributed to eminent lawyers, and that in others, by treating law more as a profeffion than as a science, the compilers exhibit no novelty of sentiment or depth of speculation. To combine general principles with Crit. Rev. VOL. XXIV. Dec, 1798.