It had been a desperate combat of mine and counter-mine even where the general circumvallation of the town was concerned, though the worst, of course, was to come when the citadel should be attacked. The batteries against the place had been increased until they counted one hundred and twelve heavy pieces and seventy mortars. On the night of the 24th of July the covered way on the right of the Scheldt was taken at heavy loss; forty-eight hours later the covered way on the left between the river and the citadel. The horn work in front of the Gate of the Seven Springs was carried on the 27th, and the isolated work between this point and the Gate of Lille upon the following day. Surville in his report, in the true French spirit of self-criticism, ascribed to the culpable failure of their defenders the loss of these outworks. But the loss, whatever its cause, determined the loss of the town. A few hours later practicable breaches had been made in the walls, ways were filled in over the ditches, and on the imminence of a general assault Surville upon the 28th demanded terms. The capitulation was signed on the 29th, and with it the commander sent a letter to Versailles detailing his motives for demanding terms for the civilian population. Finally, upon the 30th,[3] Surville with 4000 men, all that was left of his original force of 7000, retired into the citadel and there disposed himself for as a long a resistance as might be. As his good fortune decided, he was to be able to hold with this small force for five full weeks. To Marlborough is due the honour of the capitulation. The besieging troops were under his command, while Eugene directed the army of observation to the west. Marlborough put some eight thousand men into the town under Albemarle. A verbal understanding was given on both sides that the citadel would not fire upon the civilian part, nor the allies make an attack from it upon the citadel, and the siege of that stronghold began upon the following day, the 21st, towards evening. The operations against the citadel proved far more severe and a far greater trial to Marlborough's troops than those against the general circumvallation of the town. The subterranean struggle of mine and counter-mine particularly affected the moral of the allies, and after a week a proposal appeared[4] that the active fighting should cease, the siege be converted into a blockade, and only the small number of men sufficient for such a blockade be left before the citadel until the 5th of September, up to which date, a month ahead, at the utmost, it was believed the garrison could hold out. Louis was willing to accept the terms upon the condition that this month should be one of general truce. The allies refused this condition, and hostilities were resumed.[5] The force employed for containing the citadel and for prosecuting its siege had no necessity to be very large.