These things seem to have been done toward the end of August. On the 27th and 28th of that month John was at Montfort, a castle some five-and-twenty miles from Rouen, held by one of his few faithful barons, Hugh of Gournay. On the 30th, if not the 29th, he and all his available forces were back at Rouen, ready to attempt on that very night the relief of Les Andelys. The King's plan was a masterpiece of ingenuity; and the fact that the elaborate preparations needed for its execution were made so rapidly and so secretly as to escape detection by an enemy so close at hand goes far to show how mistaken are the charges of sloth and incapacity which, even in his own day, men brought against "John Softsword."[36] He had arranged that a force of three hundred knights, three thousand mounted men-at-arms, and four thousand foot, under the command of William the Marshal, with a band of mercenaries under Lou Pescaire, should march by night from Rouen along the left bank of the Seine, and fall, under cover of darkness, upon the portion of the French army which still lay on that side of the river. Meanwhile, seventy transport vessels, which had been built by Richard to serve either for sea or river traffic, and as many more boats as could be collected, were to be laden with provisions for the distressed garrison of the island fort, and convoyed up the stream by a flotilla of small warships, manned by "pirates" under a chief named Alan and carrying, besides their own daring and reckless crews, a force of three thousand Flemings. Two hundred strokes of the oar, John reckoned, would bring these ships to the French pontoon; they must break it if they could; if not, they could at least coöperate with the Marshal and Lou Pescaire in cutting off the northern division of the French host from its comrades and supplies on the left bank, and throw into the island fort provisions which would enable it to hold out till John himself should come to its rescue.