90 CONFORMATION AND ITS DEFECTS 



SICKLE OR CURBY HOCK 



In this variety of conformation (Plate XIII, fig. 3) the canon, instead of 

 occupying a vertical position, inclines more or less forward, so that the leg 

 is brought under the body, or, as it is said, the horse is " under himself 

 behind ". The effect of this is to increase the angularity of the hock and 

 give it a bent or sickle-shaped appearance. In such a disposition of jDarts 

 it results that " the column of support below the tibia being situated too 

 obliquely forward, the pressure of the weight of the body, instead of being- 

 transmitted to the ground l)y the bones exclusively, as in the vertical 

 position of this segment, causes a strain proportionable to the degree of 

 obliquity on the ligaments which unite the hock to the canon, and imposes 

 upon them an abnormal function " (Bouley). To this it might be added 

 that by bringing the hind extremities more immediately under the centre 

 of gravity, the strain on the extensor muscles and their tendons is 

 considerably augmented. 



Horses with curby hocks are not generally desirable property, although 

 for harness-work, and especially in a level country, they may prove 

 serviceable and enduring. They are not, however, adapted to carry 

 heavy weights, or to put forth severe efforts of draught without injury. 



BODY AND LIMBS 



As we have already observed, the body and the limbs make up the sum 

 of the height. In considering the latter, only those portions separate from 

 the trunk are referred to, viz. parts below the el])ow in front and the stifle 

 behind. The rest is accounted for by the depth of the chest and the abdo- 

 men. The proportion which these two parts bear to each other will vary 

 to some extent in animals of different types. All things being equal, the 

 limbs of the race-horse and other light breeds are always longer than those 

 of the heavier varieties. 



" The body containing the organs which are most essential to life, such 

 as the heart, the lungs, and the digestive apparatus, cannot be deficient 

 from excess of development, since these organs are precisely those from 

 which the animal machine draws its power and resistance. If dispro- 

 portion seems to exist in the upper part compared to the lower part, then 

 the latter is not properly constructed to support the former, but generally, 

 although excess may not be objectionable, the same cannot be said of defi- 

 ciency of development. Our machine having a weak chest, a small abdo- 

 men, Avill be without energy, without wind, and capable of very little 



