Such considerations had doubtless been at the root of the temporising policy which had been pursued after Churubusco.  But the uselessness of half-measures had then been proved.  The conviction had become general that a desperate enterprise could only be pushed to a successful issue by desperate tactics, and every available battalion was hurried forward to the assault.  Before the San Cosme Gate the pioneers were ordered up, and within the suburb pick and crowbar forced a passage from house to house.  The guns, moving slowly forward, battered the crumbling masonry at closest range.  The Mexicans were driven back from breastwork to breastwork; and a mountain howitzer, which Lieutenant Grant had posted on the tower of a neighbouring church, played with terrible effect, at a range of two or three hundred yards, on the defenders of the Gate.

By eight o’clock in the evening the suburb had been cleared, and the Americans were firmly established within the walls.  To the south-east, before the Belen Gate, another column had been equally successful.  During the night Santa Anna withdrew his troops, and when day dawned the white flag was seen flying from the citadel.  After a sharp fight with 2000 convicts whom the fugitive President had released, the invaders occupied the city, and the war was virtually at an end.  From Cerro Gordo to Chapultepec the power of discipline had triumphed.  An army of 30,000 men, fighting in their own country, and supported by a numerous artillery, had been defeated by an invading force of one-third the strength.  Yet the Mexicans had shown no lack of courage.  “At Chapultepec and Molino del Rey, as on many other occasions,” says Grant, “they stood up as well as any troops ever did."* (* Grant’s Memoirs volume 1 page 169.) But their officers were inexperienced; the men were ill-instructed; and against an army of regular soldiers, well led and obedient, their untutored valour, notwithstanding their superior numbers, had proved of no avail.  They had early become demoralised.  Their strongest positions had been rendered useless by the able manoeuvres of their adversaries.  Everywhere they had been out-generalled.  They had never been permitted to fight on the ground which they had prepared, and in almost every single engagement they had been surprised.  Nor had the Government escaped the infection which had turned the hearts of the troops to water.

September 14.

The energy of the pursuit after the fall of Chapultepec had wrought its full effect, and on September 14 the city of Mexico was surrendered, without further parley, to a force which, all told, amounted to less than 7000 men.* (* The total loss in the battles before the capital was 2703, including 383 officers.  Scott’s Memoirs.)

With such portion of his force as had not disbanded Santa Anna undertook the siege of Puebla; and the guerillas, largely reinforced from the army, waged a desultory warfare in the mountains.  But these despairing efforts were without effect upon the occupation of the capital.  The Puebla garrison beat back every attack; and the bands of irregular horse men were easily dispersed.  During these operations Magruder’s battery remained with headquarters near the capital, and so far as Jackson was concerned all opportunities for distinction were past.