While this exciting incident was being enacted, Edward was furiously assaulting the town from the land, sending his fierce stormers, who were abundantly supplied with scaling ladders, to the attack by thousands, and covering their advance by the incessant discharge of his archers, whose long and deadly shafts swept the ramparts like a hail-storm. But the Scots met the storm with indomitable bravery, fringing their walls with glittering pikes, hurling down showers of missiles upon the enemy, casting down their ladders, and sending their heavy axes through the iron skull-caps of the stormers before they could make good their foot-hold upon the ramparts. After long hours of stubborn and sanguinary toil, Edward withdrew his troops to the shelter of their entrenchments, and both parties rested after their severe and exhausting toil: but at the base of the walls, and upon the bloody ramparts many brave men slept their long death-sleep. Untamed by their repulse, the English soldiers prepared to renew their efforts, and set to work upon the construction of a huge military machine called a "Sow": this was framed of solid timber, and moved upon heavy rollers, the roof sloping and affording an efficient protection to the soldiers who toiled with pick and spade beneath its cover, intent upon undermining the walls of the beleaguered hold. The "Sow" was especially dangerous to the Scots in the present case, for the whole length of the walls being exposed to repeated assaults, they were so completely outnumbered that they were unable to spare any considerable number of men to guard against its action, and should once a breach be effected in the walls it would be impossible to arrest the pressure of Edward's stormers, who kept the hardy Scots fully employed even while their ramparts were intact.