Care must be taken not only that they possess the form and qualities necessary for the work they are likely to be employed in, but also that they are docile and easy-tempered and sound. Form differs according to breed, and upon it depends the fitness of the animal for draught or saddle purposes. For either purpose a horse should walk and trot well. Horses with deeply scarred backs (or, if for harness, shoulders), or which show signs of having been much cut with the girth (girth-galled), should not be selected, if avoidable. If for riding purposes, the withers should be neither too high nor too low, and the shoulders oblique; forearms long and muscular; chest moderately wide and deep; ribs well arched behind saddle and continued close to haunch; loins broad; hindquarters long, wide, and muscular; tail set on as near the level of the croup as possible; limbs from knees and hocks downwards short, wide laterally, with the tendons and ligaments standing well apart from the bone, and distinctly defined. Neither beneath knee nor hock should they be narrow or abruptly tied in; knees wide in front, hocks sideways. Pasterns not too long or oblique, inclined out or in, nor yet too upright; hoofs black, if possible, and circular in shape; wall smooth and even from coronet to ground, and not marked by horizontal rings; heels well spread; soles concave and strong; frogs well developed, sound, and firm. The foot in progression should be placed evenly on the ground, neither toe nor heel coming too markedly in contact with it. Coarse-bred horses, with hairy legs and large, flat feet, should never be chosen. Fore limbs should be examined for broken knees, splints, sprains of tendons and ligaments (indicated by thickening, and, if recent, by tenderness on manipulation), ring-bone (an uneven deposit of bony matter around the lower end of the pastern), side-bone (ossification of the elastic cartilages on each side of the foot toward the heels), sand-crack in hoof (usually in the inside quarter of fore foot), chronic laminitis (manifested by horse putting heels first to the ground, convex soles, walls hollow in the middle in front, bulging at toe, and made uneven by rings on surface), navicular disease (usually shown by contracted heels, very concave soles, lameness, and digging toes in the ground during walk or trot, wearing the shoe more at point of toe than elsewhere, extending limb forward and elevating heels while at rest), corns (a bruise of sole at the heels, only to be discovered by removal of shoe and paring sole at this part).