3()G THR KXRE. 



perfect pulley of the bone of tlic arm witliont friction ; the body of tlie 

 muscle is mixed witli tendinous fibres, and the insertion into the fore-arm 

 is very extensive, lest the application of such immense force should tear 

 it from its adhesions. There is sufficient strength in the apparatus ; the 

 power may be safely applied at this mechanical disadvantage ; and it is 

 applied close to the joint to give an extent and rapidity of motion Avhicli 

 could not otherwise have been obtained, and 'wdthout which the horse 

 would have been comparatively useless. 



It is sufficiently plain that the ann should be large and muscular, other- 

 wise it could not discharge all these duties. Horsemen differ on a variety 

 of other points, but here they agree. A full and swelling fore-arm is the 

 characteristic of every thorough -bi'ed horse. Whatever other good points 

 the animal may possess, if the arm is narrow in front and near the shoulder, 

 fiat on the side, and altogether deficient in muscular appeai-ance, that horse 

 is radically defective. He can neither raise his knee for rapid action, nor 

 throw his legs sufficiently forward. 



The arm should likewise be long. In proportion to the lengtli of the 

 muscle is the degree of contraction of which it is capable ; and in propor- 

 tion also to the degree of contraction will be the extent of motion in the 

 limb beneath. A racer, Avith a short aim, would be sadly deficient in stride; 

 a hunter, "vvith the same defect, would not be able to double his legs well 

 under him in the leap. There is, however, a medium in this, and the 

 advantage of length in the arm will depend on the use to which the horse 

 is applied. The lady's horse, the cavalry horse, every horse in which 

 prancing action is esteemed a beauty, and in which utility is, to a certain 

 degree, sacrificed to appearance, must not be too long in the arm. If he is 

 long there, he "will be proportionably short in the leg ; and although this 

 is an undoubted excellence, whether speed or continuance is regarded, the 

 short leg will not give the grand and im^Dosing action which fashion may 

 require. In addition to this, a horse with short legs may not have quite 

 so easy action as another whose length is in the shank rather than iii 

 the ai-m. 



THE KNEE. 



The Knee (M, p. 140, and cut p. 360), answering to the human -ui-ist, 

 constitutes the joint or joints between the arm and the shank or leg ; and 

 is far more complicated than any joint that has been yet considered. Be- 

 side the lower heads of the bone of the arm, and the upper heads of the 

 three bones of the leg, there are no less than six other bones interposed, 

 arranged in two rows, three in each row, and two others, the seventh and 

 eighth, placed behind. 



What was the intention of this complicated structui-e ? A joint between 

 the elbow and the fetlock Avas absolutely necessary to the action of the 

 horse. An inflexible pillar of that length could scarcely ha^'e been lifted 

 from the gTOund, much less far enough for rapid or safe motion. It was 

 likewise necessary that the interposing joint should be so constituted as 

 to preserve this part of the limb in a straight direction, and possess suf- 

 ficient strength to resist all common work and accidents. Being in a 

 straight dii-ection, the shock or jar between the ends of the bones of the 

 arm and the leg Avordd be dreadful, and Avould speedily inflict irreparable 

 injury. The heads of all bones are covered with cartilage, in order to 

 protect them from injury by concussion; but this Avould be altogether in- 

 sufficient here. Six distinct bones are therefore placed here, each covered 

 above anel below by a thick coating of cartilage, connected together by 

 strong ligaments, but separated by interposed fluids and membranes. The 



