On the land side, as has been seen, the city was enclosed and built out of human sight by another Gertruydenberg. On the wide estuary of the Meuse, a chain of war ships encircled the sea-front, in shape of a half moon, lying so close to each other that it was scarcely possible even for a messenger to swim out of a dark night. The hardy adventurers who attempted that feat with tidings of despair were almost invariably captured. This blockading fleet took regular part in the daily cannonade; while, on the other hand, the artillery practice from the landbatteries of Maurice and Hohenlo was more perfect than anything ever known before in the Netherlands or France. And the result was that in the course of the cannonade which lasted nearly ninety days, not more than four houses in the city escaped injury. The approaches were brought, every hour, nearer and nearer to the walls. With subterranean lines converging in the form of the letter Y, the prince had gradually burrowed his way beneath the principal bastion. Hohenlo, representative of the older school of strategy, had on one occasion ventured to resist the authority of the commander-in-chief. He had constructed a fort at Ramsdonck. Maurice then commanded the erection of another, fifteen hundred yards farther back. It was as much a part of his purpose to defend himself against the attempts of Mansfeld's relieving force, as to go forward against the city. Hohenlo objected that it would be impossible to sustain himself against a sudden attack in so isolated a position. Maurice insisted. In the midst of the altercation Hohenlo called to the men engaged in throwing up the new fortifications: "Here, you captains and soldiers," he cried, "you are delivered up here to be butchered. You may drop work and follow me to the old fort." "And I swear to you," said Maurice quietly, "that the first man who moves from this spot shall be hanged." No one moved. The fort was completed and held to the and; Hohenlo sulkily acquiescing in the superiority which this stripling--his former pupil--had at last vindicated over all old-fashioned men-at-arms.