In Scott's department the final military operations began very promptly. Immediately after the Americans took possession of the grand plaza at Mexico on the morning of September 14, a multitude of blanketed léperos crowded closely upon them. Already these miscreants had tasted the disorder they loved, for the palace had been left unguarded, and they had sacked it; and now they showed signs of turbulence. The plaza was cleared, however, and no further trouble seemed likely. But when our troops began to march away to their quarters, a shot was heard. A bullet probably intended for Worth struck Garland, and almost instantly firing from street corners, windows and the tops of houses became general, though not systematic. Thousands of convicts from the jail supported the populace, and in one way or another not a few of the better class coöperated. By Tornel's order paving stones had been taken to many of the azoteas with a view to resisting the invader step by step, and these, like every other sort of weapon, were now used.[29.2] Though surprised, the Americans promptly accepted the challenge. Skirmishers drove back the mobs. Grape and canister swept the streets. As a rule, every house from which a shot flew became a target for our heavy cannon, which seemed to shake the very foundations of the city, and when breached was immediately sacked; and sharpshooters worked effectively on towers and roofs. Scott threatened even sterner measures; and the city authorities not only put up notices, embodying his threats and imploring the people to desist from a vain and imprudent contest, but interceded personally with them in the streets. By about noon the Americans held all the points of vantage, and as evening approached, the firing died away. A fearful night ensued. It was dark and cold. No lights relieved the gloom. Wild mobs ran shouting through the streets, and the hoof-beats of American patrols resounded from square to square.[29.2] Santa Anna, finding it impossible on the morning of the fourteenth to subsist his army at Guadalupe, had ordered the infantry and heavy guns to Querétaro under General Herrera, and proceeded with four small pieces and the cavalry to San Cristóbal, a point about fourteen miles northeast of the capital. After seeing the people of Mexico view with indifference his efforts of the previous day, he expected nothing of them; but on learning of the outbreak he marched back to Guadalupe, and at a late hour sent into Mexico a small force of cavalry and infantry to investigate and assist. This met Duncan's battery and retreated; but Santa Anna, assured that on the next day there would be a rising _en masse_, erected a breastwork at the Peralvillo garita on the north side of the town, and waited.[29.2]