Sometimes tushes grow out even in one-year olds, and the animal falls away in condition until they are extracted, when it recovers its health. Should the colt at the age of fifteen to eighteen months fail to promise a fine free action of the shoulder, they do not hesitate to apply the cautery to the scapulo-humeral joint. It is generally applied in the form of a cross, the four extreme points of which are joined by a circle. Previous to the operation care is taken to trace the design with pitch if the animal be of a light colour, or with plaster if it be dark. If, again, a colt's knees are ill-shaped, or indicate a predisposition to bony tumours or to thickening, fire is applied in three parallel lines. Lastly, if any apprehension is felt of the colt becoming too straight either in front or behind, they fire the fetlock joint but only on the front part, which shows that the Arabs understand the tendons and treat them carefully. The fire is usually applied with a sickle. In performing this operation they avoid as much as possible the great heats of summer. The most favourable season is the end of autumn or the beginning of spring: there are fewer flies then, and the temperature is cooler. The education of a colt should commence when eighteen months old, because it is the only way to make him thoroughly docile, and also because the development of the spleen is thus checked—a very important point in the opinion of the Arabs. If he is first of all mounted at a later period, he may look stronger to the eye, but in reality he will be inferior in patience and in speed. "Every horse inured to fatigue brings good fortune."[36] And Heaven knows how the Arab horse is inured to fatigue! So to speak, he is always on the march. He travels with his master who is one of the greatest travellers on horseback in the world. He travels to seek his food. He traverses long distances to find water; and this sort of life renders him abstinent, not easily tired, and ready for anything. It must be admitted that that is a method of training horses not easily surpassed. I repeat, for I cannot too strongly insist on this capital point, the opinion of the Arabs is unanimous in favour of the education of the colt beginning at a very early age. In acting otherwise, there is a risk, they imagine, of having an unmanageable horse, or one heavy and clumsy. Exercise, on the contrary, accustoms the horse to submission, gives strength to the joints while rendering them supple, imparts firmness to the bones, develops the muscles, and brings out that power of enduring fatigue without which the animal is nothing more than source of outlay without any return for it.