The rota was a wooden cylinder, open on one side, that was built inside a wall of a monastery; it was used for exchanging mail and food with cloistered clergy, being their only communication with the world. It was usually about 50 centimeters wide by 30 centimeters high, and its opening did not permit visual or tactile contact with the uncloistered. Messages or food were put into the cylinder, then the rota was revolved so that the opening faced the other side. Monks were stationed close by or were notified that someone had turned the wheel by various mechanisms. In some cases, especially at night and in winter, the rota was filled by the monks with food, and left there for the poor, to give them something to eat without them having to ask. The rota was also used by those mothers who didn't want to (or couldn't) keep their (often illegitimate) newborn babies. They left them in the safe hands of monks or nuns, their anonymity being guaranteed by the rota. In some dioceses the instrument was abolished to discourage this latter use.