The place of the cantor in the church was always on the right hand of the choir; that of his assistant, the _succentor_, or sub-cantor, was on the left. It was part of the cantor’s duty to move about the choir when it was necessary to regulate the singing, and especially when any Prose, or long _Magnificat_ with difficult music was being sung. Above all things, he had to guard against mistakes, or even the possibility of mistakes, in the divine service by every means in his power. With this end in view, he was instructed to select only music that was known to all, and to see that it was sung in the traditional manner. To guard against faults in reading and singing he was obliged by his office to go over the Lessons for Matins with the younger monks, and to hear the reader in the refectory before the meals, in order to point out defects of pronunciation and quantity, as well as to regulate the tone of the voice and the rate of reading. When the abbot had to give out an Antiphon or Responsory on one of the greater feasts, the cantor always attended him, and helped him if there were need. If the abbot was unable to take any of his duties in church in the way of singing, such as celebrating the High Mass or intoning the Antiphons at the _Benedictus_ and _Magnificat_, the cantor took them as part of the duties of his office. On all greater feasts of the second class, the cantor, by virtue of his office, gave out the Antiphon at the _Benedictus_ and at the _Magnificat_. At the Mass and other solemn parts of the Divine Office on these occasions, he directed the choir with his staff of office: assisted on first-class days by six of the brethren in copes, and on feasts of the second class by four. His side of the choir was always to take up any psalm he had intoned; the other side of the choir, under the direction of the sub-cantor, doing the same in regard to what he intoned.