4. It is convenient to begin with the lowest grade and work upwards. The apprentice was, as may be imagined, the object of a somewhat keen solicitude. Apprenticeship, in "small" industry, with which it was intimately associated, was the means of maintaining that professional skill on which the guild prided itself. The apprentice was a child whom his parents or guardians wished to be taught a trade as soon as he was ten or twelve years of age, although there was no fixed age limit. A master was found who would take him. Every instructor must be a master: he must also be of good life and character, endowed with patience, and approved of by the officers of the guild. If he were recognized as capable of carrying out his duties, the two parties bound themselves by a contract, often verbal, often also made before a notary. This fixed the length of the apprenticeship, which varied greatly in different trades; for it might cover from one to six, eight, ten, or twelve years; sometimes it stipulated for a time of probation--usually a fortnight--during which time either side could cancel the agreement. The apprenticeship was not free of expense, at any rate to begin with, and the child's guardians paid an annual fee in corn, bread, or money. In return, the child received his lodging, food, clothes, washing, and light, and was supervised and taught in the master's house. Certain contracts contain special clauses: one states that the family will supply clothes and boots; another, that the apprentice shall receive a fixed salary after a certain time; another provides for the circumstances under which the engagement may be cancelled.[10] The apprentice had certain obligations, which sometimes, in spite of his youth, he solemnly swore to keep (the oath has never been so much used as in the Middle Ages). He promised to be industrious and obedient, and to work for no other master. The master, on his side, promised to teach him the secrets of his craft, to treat him "well and decently in sickness as in health," and certain contracts add, "provided that the illness does not last longer than a month." Naturally these duties carried with them certain rights. The master might correct and beat the apprentice, provided that he did it himself; a contract drawn up with a rope-maker in Florence says, "short of drawing blood." It often happened that the apprentice, sick of work or in a fit of ill-temper, ran away from his master; a limit was then fixed for his return, and his place was kept for him during his absence, which sometimes lasted quite a long time (it has been known to continue as long as twenty-six weeks). If he returned within the time limit he was punished but taken back; but if he indulged in three such escapades he was dismissed, his parents had to indemnify the master, and the truant was not allowed to go back to the craft which he had abandoned.