CHAPTER XIV.
1847.
DIFFICULTIES OF THE ADVANCE—THE PEDREGAL—SAN ANTONIO—HACIENDA—RELATIVE POSITION OF AMERICAN AND MEXICAN ARMIES—PATH OVER THE PEDREGAL TO CONTRERAS—VALENCIA DISCONCERTS SANTA ANNA'S PLAN OF BATTLE—AMERICAN ADVANCE AND VICTORY AT CONTRERAS—SAN ANTONIO TURNED BY WORTH—BATTLE OF CHURUBUSCO—BATTLE AT THE CONVENT AND TETE DE PONT—THEIR CAPTURE—FLIGHT OF THE MEXICANS.
In order to understand the ensuing military movements, it will be proper for the reader to study the map of the valley, and acquaint himself fully with the relative posture of both parties. The plans of both generals in chief were well made; but the blunders and obstinacy of the Mexican second in command disconcerted Santa Anna's desired combination, and ultimately opened the ground to the American advance with more ease than was anticipated.
We will sketch rapidly the military value of the arena upon which the combatants stood on the 18th of August, 1847.
Let us imagine ourselves beside General Scott, standing on one of the elevations above the town of San Agustin de las Cuevas, at the base of the southern mountain barrier of the valley, and looking northward towards the capital. Directly in front, leading to the city, is the main road, the left or western side of which, even from the gate of San Agustin to the Hacienda of San Antonio, and thence westwardly to San Angel, forms, together with the bases of the southern and western mountains about St. Geronimo and Contreras, a vast basin, ten or twelve square miles in extent, covered with the Pedregal or the field of broken lava which we have already mentioned. This mass of jagged volcanic matter, we must remember, was at that time barely passable with difficulty for infantry, and altogether impassable for cavalry or artillery, save by a single mule path. North, beyond the fortified hacienda and headquarters of Santa Anna at San Antonio, the country opened. A line of field works, the lake of Xochimilco, a few cultivated farms, and vast flooded meadows, were on its right to the east, but from the hacienda, a road branches off to the west, leading around the northern edge of the Pedregal or lava field through Coyoacan and San Angel, whence it deflects southwardly to Contreras. The main road, however, continues onward, northwardly, from the hacienda of San Antonio, until it crosses the Churubusco river at the strong fortification we have described. Beyond Churubusco the highway leads straight to the gate of San Antonio Abad, whence a work had been thrown north-westwardly towards the citadel. The city of Mexico, built on the bed of an ancient lake, was on a perfect level, nor were there any commanding or protecting elevations of importance around it within two or three miles, and the first of these, beyond this limit, were chiefly on the north and west.
Thus, General Santa Anna, in front, on the main road to the city, at the massive fortified hacienda of San Antonio, blocked up the highway in that direction, protected on his right by the barrier of the Pedregal; and by the lake of Xochimilco, the field works, and the flooded country on his left. General Valencia had been placed by him with his troops at San Angel, on the western edge of the valley, and at the village of Coyoacan, a little further east in the lap of the valley, on roads communicating easily with his position at San Antonio, while they commanded the approaches to the city by the circuitous path of the Pedregal around the edge of the valley from San Agustin de las Cuevas, through Contreras or Padierna. Valencia and Santa Anna were consequently within supporting distance of each other; and in their rear, in front of the city, were the fortifications of Churubusco. General Scott, with the whole American army was, therefore, apparently hemmed in between the lakes and the Pedregal on his flanks; the Mexican fortifications and army in front; and the steep mountains towards Cuernavaca in his rear. He was obliged, accordingly, either to retreat by the defiles through which he had advanced from Chalco,—to climb the steeps behind him and pass them to the tierra caliente,—to force the position in front at the hacienda of San Antonio,—or to burst the barrier of the Pedregal on his left, and, sweeping round the rim of the valley, to advance towards the capital through the village of San Angel. Such were some of the dangers and difficulties that menaced Scott on his arrival at San Agustin. He was in the heart of the enemy's country, in front of a capital aroused by pride, patriotism and despair, and possessing all the advantages of an accurate knowledge of the ground on which it stood, or by which it was surrounded. Scott, on the other hand, like the mariner in storm on a lee shore, was obliged to feel his way along the dangerous coast with the lead, and could not advance with that perfect confidence which is ever the surest harbinger of success.
The reconnoissances of the American engineers which had been pushed boldly, in front, on the main road, to the north, by the hacienda of San Antonio, soon disclosed the difficulty in that direction. But among the mass of information which the American General received at Puebla, his engineers learned that there was a pathway through this Pedregal whose route had been indicated by the spies with sufficient distinctness and certainty to justify a hope that he might be able to render it practicable for his whole army, and, thus, enable him to turn the right flank of the Mexicans' strongest positions. There is no doubt, as subsequent events demonstrated, that the ground in the neighborhood of Contreras, where the road descends from the mountains and barrancas towards San Angel was of great importance to the Mexicans in the defence of the various modes of access to the city, and it is unquestionable that a strong post should have been placed in that quarter to cripple the American advance. It is stated by Mexican writers, that General Mendoza, with two members of his topographical corps had reconnoitred this route and pass, and pronounced it "absolutely indefensible." It is probable, therefore, that no general action, involving the fortunes of a division, or of a large mass of the Mexican army, should have been risked among the ravines between the mountains and the Pedregal near Contreras; yet we do not believe that it should have been left by Santa Anna without a force capable of making a staunch resistance.
We are now acquainted with the ground, and with the positions of the two armies. Scott's plan was to force a passage by either or both of the two adits to the levels of the valley in front of the city, while Santa Anna's, according to his manifesto dated subsequently on the 23d of August, was to have made a concerted retrograde movement with his troops, and to have staked the fortunes of the capital on a great battle, in which all his fresh, enthusiastic, and unharmed troops would have been brought into a general action against the comparatively small American army, upon an open ground where he would have had full opportunity to use and manœuvre infantry, cavalry and artillery.