Fisheries are important sources of rent. Payments of eels are enumerated by hundreds and thousands. Herrings appear to have been consumed in vast numbers in the monasteries. Sandwich yielded forty thousand annually to Christ Church in Canterbury. Kent, Sussex, and Norfolk appear to have been the great seats of this fishery. The Severn and the Wye had their salmon fisheries, whose produce king, bishop, and lord were glad to receive as rent. There was a weir for Thames fish at Mortlake. The religious houses had their _piscinae_ and _vivaria_--their stews and fish-pools. _Domesday_ affords us many curious glimpses of the condition of the people in cities and burghs. For the most part they seem to have preserved their ancient customs. London, Winchester, and several other important places are not mentioned in the record. We shall very briefly notice a few indications of the state of society. Dover was an important place, for it supplied the king with twenty ships for fifteen days in a year, each vessel having twenty-one men on board. Dover could therefore command the service of four hundred and twenty mariners. Every burgess in Lewes compounded for a payment of twenty shillings when the king fitted out a fleet to keep the sea. At Oxford the king could command the services of twenty burgesses whenever he went on an expedition; or they might compound for their services by a payment of twenty pounds. Oxford was a considerable place at this period. It contained upward of seven hundred houses; but four hundred and seventy-eight were so desolated that they could pay no dues. Hereford was the king's demesne; and the honor of being his immediate tenants appears to have been qualified by considerable exactions. When he went to war, and when he went to hunt, men were to be ready for his service. If the wife of a burgher brewed his ale, he paid tenpence. The smith who kept a forge had to make nails from the king's iron. In Hereford, as in other cities, there were moneyers, or coiners. There were seven at Hereford, who were bound to coin as much of the king's silver into pence as he demanded. At Cambridge the burgesses were compelled to lend the sheriff their ploughs. Leicester was bound to find the king a hawk or to pay ten pounds; while a sumpter or baggage-horse was compounded for at one pound.