The exterior of the horse . ute the phalangal segment, as M. Pader^ believes, butit is the entire digital re-gion, the hoof included. These form, it is true,a broken lever composedof two pieces (1st, the firsttwo phalanges ; 2d, thehoof), but their successivemovements, always in thesame direction, are so closelyassociated as to give to thetotal displacement a unityanalogous to that producedby a rigid lever, OB (), extending from thesoil, B, to the fetlock, 0. With a quantity ofmovement that varies ac-cording to the weight ofthe body and the velocityof the gait, the extremity, B,of this
The exterior of the horse . ute the phalangal segment, as M. Pader^ believes, butit is the entire digital re-gion, the hoof included. These form, it is true,a broken lever composedof two pieces (1st, the firsttwo phalanges ; 2d, thehoof), but their successivemovements, always in thesame direction, are so closelyassociated as to give to thetotal displacement a unityanalogous to that producedby a rigid lever, OB (), extending from thesoil, B, to the fetlock, 0. With a quantity ofmovement that varies ac-cording to the weight ofthe body and the velocityof the gait, the extremity, B,of this segment comes, ateach step, in contact withthe ground, xy, Avliich necessarily reacts in proportion to the actionwhich it communicates to the hoof. It is easy to convince ourselvesthat this action is also modified by the variations in the length of thedigital region. Let the line BH represent the force which, acting at the extremity, B, of thelever, BOA, tends to rotate it around the point 0, and, consequently, to close the. Fig. 100. Pader, loc. cit. POSTERIOR MEMBER. 303 angle BOC, by antagonizing the muscular action, M, which is exercised at theextremity, A, of the same lever. In this case, the fetlock becomes the fixed pointor fulcrum and the lever belongs to the first class. Let us determine, as above, the arms of the lever of the forces, BH andAM, by inserting from the fixed point a line perpendicular to their direction ;these arms evidently are O^and OA. Now let us lengthen the lever OB to OD, and we will see that the arm ofthe force, BH, becomes 01, while that of ^3/will always remain OA. Thus, the longer the pastern the more the reaction of the soilagainst the weight of the body augments and fatigues the tendons andthe ligaments which are inserted, at A, upon the sesamoid bones. Thecauses which tend to augment the length of the phalangal region arevery significant, exception being made, of course, of the dimensions ofthe bones. First among these we will place the elong
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Keywords: ., bookcentury1800, bookdecade1890, booksubjecthorses, bookyear1892
