The exterior of the horse . oposi-tion with which we started /AG „. AC\ (—equalling—). The angular dis-placement of the shortarm, CD, is thereforemore extensive for anequal contraction orshortening of the mus-cles than that of thelong arm, CD. In addition, the ex-tensors of the shotdderAB are longer thanthose of the shoulderAB. Consequently, themuscles of the latter are obliged to shorten themselves more for theproduction of the displacement DG, which the extensors of AB willeffect without fatigue. Finally, as the effort of a muscle varies according to certain condi-tions, among others ^vith t
The exterior of the horse . oposi-tion with which we started /AG „. AC\ (—equalling—). The angular dis-placement of the shortarm, CD, is thereforemore extensive for anequal contraction orshortening of the mus-cles than that of thelong arm, CD. In addition, the ex-tensors of the shotdderAB are longer thanthose of the shoulderAB. Consequently, themuscles of the latter are obliged to shorten themselves more for theproduction of the displacement DG, which the extensors of AB willeffect without fatigue. Finally, as the effort of a muscle varies according to certain condi-tions, among others ^vith the resistance to be displaced, it follows thatthe shoulder AB will produce the extension of the arm CD moreeasily than AB that of the arm CD, since the former is shorter andconsequently less heavy than the latter. Thus the length of the shoulder in comparison with that of thearm should be as great as possible, for the reason that it effects agreater displacement of the humerus with a more feeble muscular Fig. 58. ANTERIOR MEMBER. 207 Direction.—Another element in the beauty of the shoulder of therace-horse in particular resides in its obliquity. This direction is indicated by an imaginary line which passes fromthe summit of the withers through the centre of the scapulo-humeral articulation. Observation has demonstrated that this linepasses a little posterior to the scapular spine. Marked obliquity of the shoulder has always been considered abeauty, or point of excellence, inclose relation with the productionof speed ; while in its relation withthe development of force it is com-paratively indiiferent. Nothing ismore easy of comprehension. Let us represent (Fig. 59) OA and0A\ two shoulders of unequal obliq-uities, and OB, the humerus on whichthey operate. Let us suppose, also, thatAOB^ be the maximum opening of theangle AOB. All things being equal, the limit ofextension of the humerus on the shoul-der OA will be carried to B^, since,from the anatomical uni
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Keywords: ., bookcentury1800, bookdecade1890, booksubjecthorses, bookyear1892
