It was a bright day, clear, but not quite frosty. The efforts of the besieging force were concentrated against a space of about two hundred and fifty yards, containing two curtains and two towers, one of which was the square barbican, the other had a pointed roof that was built to overlap, resting on a stone machicolade, and by this means a row of dangerous crenelets between the roof and the masonry grinned down at the nearer assailants, and looked not very unlike the grinders of a modern frigate with each port nearly closed. The curtains were overlapped with penthouses somewhat shattered by the mangonels, trebuchets, and other slinging engines of the besiegers. On the besiegers' edge of the moat was what seemed at first sight a gigantic arsenal, longer than it was broad, peopled by human ants, and full of busy, honest industry, and displaying all the various mechanical science of the age in full operation. Here the lever at work, there the winch and pulley, here the balance, there the capstan. Everywhere heaps of stones, and piles of fascines, mantelets, and rows of fire-barrels. Mantelets rolling, the hammer tapping all day, horses and carts in endless succession rattling up with materials. Only, on looking closer into the hive of industry, you might observe that arrows were constantly flying to and fro, that the cranes did not tenderly deposit their masses of stone, but flung them with an indifference to property, though on scientific principles, and that among the tubs full of arrows, and the tar-barrels and the beams, the fagots, and other utensils, here and there a workman or a soldier lay flatter than is usual in limited naps, and something more or less feathered stuck in them, and blood, and other essentials, oozed out. At the edge of the moat opposite the wooden tower, a strong penthouse, which they called “a cat,” might be seen stealing towards the curtain, and gradually filling up the moat with fascines and rubbish, which the workmen flung out at its mouth. It was advanced by two sets of ropes passing round pulleys, and each worked by a windlass at some distance from the cat. The knight burnt the first cat by flinging blazing tar-barrels on it. So the besiegers made the roof of this one very steep, and covered it with raw hides, and the tar-barrels could not harm it. Then the knight made signs with his spear, and a little trebuchet behind the walls began dropping stones just clear of the wall into the moat, and at last they got the range, and a stone went clean through the roof of the cat, and made an ugly hole.