In the Middle Ages, when learning was neglected elsewhere, such literature as there was found a refuge in monasteries. In every great abbey there was an apartment called scriptorium, or domus antiquarii, where writers were constantly employed in copying psalters, missals, Church music, and such other works as they could obtain. The monks in these writing-rooms were enjoined to pursue their occupations in silence, and cautiously to avoid mistakes in grammar, spelling, or pointing. In some cases authors prefixed to their works a solemn adjuration to the transcribers to copy them correctly. When a number of copies of the same work was to be made, it was usual to employ several persons at the same time in writing; each person, except the writer of the first skin, began where his fellow was to leave off. Sometimes they wrote after another person, called the dictator, who held the original and dictated; hence the errors in orthography in many ancient MSS. These scriptoria were ordinarily so arranged that benches were placed one behind another for the copyists, so that, a master or person standing at one end and naming a word or musical note, it could be quickly copied by all, each naming it in succession. These writing monks were sometimes distinguished by the name of librarii, a term applied to the common scriptores who gained a living by writing, but their more usual designation was antiquarii. Isidore of Seville says, "The librarii transcribed both old and new works, the antiquarii only those that were ancient; from hence they derived their name." It was the duty of the librarian, or precentor of the monastery, to provide the writing-monks with the books they were to copy, and with the materials necessary, for their occupation; they were also forbidden to write anything without his permission. The junior monks were usually employed in the transcription of ordinary books, but it was ordained that "the gospels, psalters, and missals should be carefully written by monks of mature age." Nuns were occasionally employed in a similar way.