invaders. Officers and men were paroled not to serve during the war unless exchanged; the officers retained their side-arms, but the muskets of the rank and file were piled in front of the conquerors. All public property of every name and kind was handed over with the surrendered place.
Nearly two weeks were required to get the army in readiness for an advance into the interior, which was led on the 8th of April by General Twiggs. The Mexicans were severely defeated, and their army was cut up and routed at Cerro Gordo, where Scott lost a total of four hundred and thirty-one killed and wounded out of a force of eighty-five hundred of all arms. The Mexicans left upwards of a thousand men dead on the field of battle. La Hoya, Perote, and Puebla were occupied with little opposition, and at Puebla General Scott waited for reinforcements, which arrived during June and July. Early in August, with a force of not quite eleven thousand men, he advanced towards the valley of Mexico, leaving Colonel Childs with a garrison of eleven hundred men to hold Puebla. General Twiggs led the column with his division, which found the ascent of the Cordilleras very difficult; on the third day of the march the division reached the crest of the ridge and looked down into the valley of Mexico, where the soldiers camped that night on the borders of Lake Chalco.
The delay of General Scott on the road from Vera Cruz had been utilized by the Mexicans under the leadership of Santa Anna, who had collected an army of 25,000 men to oppose and expel the invaders. The defences of the city had been strengthened, and all the natural advantages of its position were utilized. Between the American army and the city lay the lakes Xochimilco and Chalco, bordered by marshes which extended around the city on the west and south. The only approaches were by causeways, which had been fortified at several points; on the
