It must be remembered, however, that jumping cannot be perfectly taught some horses - indeed, there are some which are unteachable; while to others it comes naturally.
The colt must be ridden quietly at his fences and with somewhat light hands, so as to leave his head easy, allowing him to take his jumps as a matter of course, and merely keeping his head straight at them.
Breaking to Harness is quite as important, if not more so, than breaking to saddle, and requires as much attention, patience, tact, and kindness. The same preliminary training is necessary as regards handling. An easy-fitting, well-stuffed, and smooth-lined collar, opening at the top, should be provided; it ought to be put on, and the colt exercised in it for a short time, then the other portions of harness may be added, and exercise or longeing given in them. Next day attach ropes, long leather straps (reins) to the collar, the ends of which should be held and gently pulled at by an assistant, while another leads the animal, starting and stopping him now and again, but never making him unsteady by jerking pulls, and allowing the lines to touch his hocks and quarters now and again.
It is best to break to harness without blinkers, for reasons already given; but if they are to be used, now is the time to put them on.
To accustom him to the pole of the break, that part should be placed beside him, laid against his body, and rubbed over him. He must on no account be alarmed by it, but should tolerate it about his legs, and in a day or two, when he understands it, he will have no fear of it. He ought also to be led about carriages and near carriage wheels, and alongside horses in harness, so as to become used to wheels behind him. Then he may be put in a light break, along with a steady, but free, old horse, and gently and encouragingly started to travel along a straight, level road, the harness being sound and well put on, and the break attachments strong and secure. It may be well to have a man run alongside the colt for a short distance to encourage and steady him, going slow at first; indeed, a walking pace is the best to begin with. Only a short journey should be taken for two or three days, and at the end of each the shoulders and neck must be carefully examined to prevent chafing from the collar. Should the skin become tender, there is nothing better than alum solution sponged over it.
The colt ought to be driven on the near and off side alternately.
When steady and obedient in double harness, if intended for single harness also, the colt may be trained in a light, but strong, carriage - two-wheeled, if possible. The harness must be good, and a kicking strap is necessary with strong breeching.
Care is needed in putting him between the shafts for the first time, and when gently started he should be led for some distance on a level smooth road, until he is reassured and calm. The whip must not touch him, and starting should always be quiet and steady. Sudden stopping and jibbing must be carefully guarded against; the harness and bit should fit well and comfortably, and on the management of the reins will depend the development of the horse's intelligence, the sensitiveness of his mouth, and his obedience.
It is needless to say that none but good-tempered skilful men should be allowed to break horses to harness; while they are even more necessary to cure horses of those bad habits and vices so readily acquired during early years, through bad breaking and training.