“They advanced slaves gradually, taking account of their services, their courage, and their merit. Thus a slave who had just been purchased served for one year on foot. Clothed in a cotton tunic, he walked beside the stirrup of his chief; they did not have him mount on horseback either in public or in private, and he would be punished if it were learned that he had done so. When his first year of service was ended, the head of the chamber informed the chamberlain, and the latter gave the slave a Turkish horse which had only a rope in its mouth, a bridle and a halter in one. When he had served one year on horseback, whip in hand, he was given a leathern girth to put about the horse. The fifth year they gave him a better saddle, a bridle ornamented with stars, a tunic of cotton mixed with silk, and a mace which he suspended by a ring from his saddle-bow. In the sixth year he received a garment of a more splendid color; and in the seventh year, they gave him a tent held up by a pole and fixed by sixteen pegs: he had three slaves in his suite, and he was honored with the title of head of a chamber; he wore on his head a hat of black felt embroidered with silver and he was clothed with a silk robe. Every year he was advanced in place and dignity; his retinue and his escort were increased until the time when he reached the rank of chief of squadron and finally that of chamberlain. Though his capacity and merit might be generally recognized, though he had done some noteworthy deed and had acquired universal esteem and the affection of his sovereign, he was obliged nevertheless to wait until the age of thirty-five years before obtaining the title of _emir_ and a government.”[29] In this system of the training of slaves for war and government lay the nucleus of the fundamental institution of the Ottoman state, which, together with the institution based on the Sacred Law, was to sum up practically the entire organized life of the Ottoman nation. Under the Samanids it was Turkish boys who were thus educated by Arabs and Persians, but the Ottomans were later to apply the same principle to the education of Christian youth. The Seljuk Turks brought most of the ideas that have been mentioned into Asia Minor. They served chiefly as mediators between the older Turkish, Persian, and Mohammedan systems and that of the Ottomans. Besides adding some features out of their own experience, such as a method of book-keeping, and handing on a taste for constructing public buildings like caravanserais, khans, and mosques, they gave rise to several important religious orders which were to have a place in Ottoman life.