Education was begun at an early age. Paulinus of Pella began when he was five,[640] and Ausonius took charge of children in their infancy.[641] At fourteen or fifteen the boy usually left the grammarian. Paulinus, who was probably retarded by the difficulty he found with Latin, was still in his grammarian’s school at fifteen.[642] If, as it appears, the law-course lasted five years, law students who went to Rome from Gaul would spend only a year or so in the school of the rhetor. For the emperor forbade students to continue their studies at Rome after the age of twenty, when they were removed by force if they omitted to return. ‘His sane qui sedulo operam professoribus navant, usque ad vicesimum aetatis suae annum Romae liceat commorari. Post id vero tempus qui neglexerit sponte remeare, sollicitudine praefecturae etiam invitus[643] ad patriam revertatur.’[644] Such was the stringent enactment of Valentinian in A.D. 370. We hear of students attached to the ‘Corpora’ who continued their studies at Rome after their twentieth year.[645] But it appears that the general age for leaving the rhetor’s school was, at any rate, before twenty. Pueros ... formasti rhetor metam prope puberis aevi, says Ausonius to Exsuperius,[646] which means that fifteen was a common age for boys to be at the rhetor’s school. About school-hours we know very little. It does not seem likely that the grammarian had so many hours per week for each of the seven liberal arts. What he aimed at was extensive reading, primarily for philological and literary knowledge, and only secondarily for such historical and scientific facts as came under Capella’s various heads. ‘The grammarian’, says Seneca, ‘attends to language, and, if he wishes to go farther afield, to history, while the utmost limit of his activities is poetry.’[647] ‘If he wishes to go farther afield’ is significant: the system was an elastic one. Of the total number of teaching hours there is only one indication. Ausonius sends the teacher Ursulus six philippi, the usual New Year’s gift from the emperor which Ursulus had not received, and says that they are ‘As many as the men to whom the fates of the Romans and the Albans were entrusted, and as many as his teaching hours at school and the hours he sits at home’.[648] Denk, therefore, seems to be wrong when he says of the teachers[649] that they had no limitations of subject or method or time. When this schoolday of six hours started in Gaul we do not know; but it is probable that it began fairly early in the morning and went on into the early afternoon. This was the case at Antioch in the fourth century;[650] and Augustine says that the teacher is kept busy in the hours before noon.[651]