92 JUDGING HORSES 



understand what takes place when the horse "lifts" in the 

 starting or moving of a load or in merely projecting his own 

 body forward in locomotion. 



Mechanical Structure.' — The structure of the horse, mechan- 

 ically considered, consists of a trunk suspended by an arch, 

 the vertebral column, supported at each end by four vertical 

 columns, the legs, the anatomical features of which have 

 already been described. Greater weight is borne on the 

 forelegs because the appended head and neck bring the centre 

 of gravity well forward of the centre of the body. The 

 arrangement by which the body is slung between the two 

 forelegs by the great pectoral muscles and the slope of 

 shoulder and pastern provide for the supporting of this 

 weight, especially during locomotion, with least concussion. 

 The centre of gravity being displaced further forward when 

 the horse is in motion, still greater weight is thrown on 

 the forelegs, the hindlegs serving as propellers. The 

 articulation of the thigh directly with the pelvis conveys the 

 propulsive effort throughout the entire length of the spinal 

 column. The supportive action of the forelegs meets the 

 propulsive action of the hindlegs in such a way as to restore 

 the equilibrium of the body. 



The joints of the leg are hinge joints, capable of motion 

 in two directions only, flexion and extension, while the joints 

 of the hip and shoulder, points at which the legs articulate 

 with the body, are ball-and-socket joints, which permit of a 

 rotary motion. The legs, generally speaking, are therefore 

 capable of alternate flexion and extension, which takes place 

 in the order named, although the flexion of the leg as a whole 

 may involve the extension of some one joint, as in the case 

 of the shoulder at the commencement of flexion of the leg. 



Relation of Bone and Muscular Development. — In accordance 

 with the use of the horse, it is necessary to understand the 

 relation of the bones and muscles, especially in determining 

 normal value, quality of structure, and the amount of natural 

 muscular development. In passing judgment on a horse, 

 the general shape of the bony framework and its correlation 

 with the muscles should be kept in mind, as it will be helpful 

 in determining the relative merits of animals in low or medium 



> G'aj', Principles and Practice of Judging Live Stock. 



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