THE largest and finest western range still left in England is at Fountains. The vista of arches is quite a long one, and is often wrongly called the cloisters. This vista, however, is modern, for the range was cut up into several compartments. Of the twenty-two bays, the southern twelve formed the frater of the conversi, or lay brethren. There were lay brethren in all the Orders up to the Black Death in 1348—9, when they almost disappeared. The Cistercian conversi were of special importance, and special regulations for them are laid down in the Carta Caritatis. They were sometimes equal to the monk in social position, but they were not allowed to become monks. It was absolutely forbidden to teach them letters. Ambition was, at all costs, to be rooted out. Like the monk, the lay brother took the three vows of poverty, chastity, and obedience. He had to promise obedience de bono, whereas the monk promised only secundum regulam Sancti Benedicti. At Waverley about the end of the twelfth century there were 70 monks and 120 conversi. At Louth Park a little later there were 66 monks and 150 conversi. We do not know the number at Fountains, but the size of the frater indicates a large community. The lay brethren's dorter was over it, and occupied the whole length and breadth of the range: it was reached by a staircase on the west side, and had its own night stairs descending into the church.