General Scott, with Worth's division, was now occupying Tacubaya, a village some four miles south-west of the City of Mexico, and extending from the base up the mountain-side for the distance of half a mile. More than a mile west, and also a little above the plain, stands Molino del Rey. The mill is a long stone structure, one story high and several hundred feet in length. At the period of which I speak General Scott supposed a portion of the mill to be used as a foundry for the casting of guns. This, however, proved to be a mistake. It was valuable to the Mexicans because of the quantity of grain it contained. The building is flat roofed, and a line of sand-bags over the outer walls rendered the top quite a formidable defence for infantry. Chapultepec is a mound springing up from the plain to the height of probably three hundred feet, and almost in a direct line between Molino del Rey and the western part of the city. It was fortified both on the top and on the rocky and precipitous sides.
The City of Mexico is supplied with water by two aqueducts, resting on strong stone arches. One of these aqueducts draws its supply of water from a mountain stream coming into it at or near Molino del Rey, and runs north close to the west base of Chapultepec; thence along the centre of a wide road, until it reaches the road running east into the city by the Garita San Cosme; from which point the aqueduct and road both run east to the city. The second aqueduct starts from the east base of Chapultepec, where it is fed by a spring, and runs north-east to the city. This aqueduct, like the other, runs in the middle of a broad road-way, thus leaving a space on each side. The arches supporting the aqueduct afforded protection for advancing troops as well as to those engaged defensively. At points on the San Cosme road parapets were thrown across, with an embrasure for a single piece of artillery in each. At the point where both road and aqueduct turn at right angles from north to east, there was not only one of these parapets supplied by one gun and infantry supports, but the houses to the north of the San Cosme road, facing south and commanding a view of the road back to Chapultepec, were covered with infantry, protected by parapets made of sandbags. The roads leading to garitas (the gates) San Cosme and Belen, by which these aqueducts enter the city, were strongly intrenched. Deep, wide ditches, filled with water, lined the sides of both roads. Such were the defences of the City of Mexico in September, 1847, on the routes over which General Scott entered.
Prior to the Mexican war General Scott had been very partial to General Worth — indeed he continued so up to the close of hostilities — but, for some reason, Worth had become estranged from his chief. Scott evidently took this coldness somewhat to heart. He did not retaliate, however, but on the contrary showed every disposition to appease his subordinate. It was understood at the time that he gave Worth authority to plan and execute the battle of Molino del Rey without dictation or interference from any one, for the very purpose of restoring their former relations. The effort failed, and the two generals remained ever after cold and indifferent towards each other, if not actually hostile.
The battle of Molino del Rey was fought on the 8th of September. The night of the 7th, Worth sent for his brigade and regimental commanders, with their staffs, to come to his quarters to receive instructions for the morrow. These orders contemplated a movement up to within striking distance of the Mills before daylight. The engineers had reconnoitred the ground as well as possible, and had acquired all the information necessary to base proper orders both for approach and attack.
By daylight on the morning of the 8th, the troops to be engaged at Molino were all at the places designated. The ground in front of the Mills, to the south, was commanded by the artillery from the summit of Chapultepec as well as by the lighter batteries at hand; but a charge was made, and soon all was over. Worth's troops entered the Mills by every door, and the enemy beat a hasty retreat back to Chapultepec. Had this victory been followed up promptly, no doubt Americans and Mexicans would have gone over the defences of Chapultepec so near together that the place would have fallen into our hands without further loss. The defenders of the works could not have fired upon us without endangering their own men. This was not done, and five days later more valuable lives were sacrificed to carry works which had been so nearly in our possession on the 8th. I do not criticise the failure to capture Chapultepec at this time. The result that followed the first assault could not possibly have been foreseen, and to profit by the unexpected advantage, the commanding general must have been on the spot and given the necessary instructions at the moment, or the troops must have kept on without orders. It is always, however, in order to follow a retreating foe, unless stopped or otherwise directed. The loss on our side at Molino del Rey was severe for the numbers engaged. It was especially so among commissioned officers.
I was with the earliest of the troops to enter the Mills. In passing through to the north side, looking towards Chapultepec, I happened to notice that there were armed Mexicans still on top of the building, only a few feet from many of our men. Not seeing any stairway or ladder reaching to the top of the building, I took a few soldiers, and had a cart that happened to be standing near brought up, and, placing the shafts against the wall and chocking the wheels so that the cart could not back, used the shafts as a sort of ladder extending to within three or four feet of the top. By this I climbed to the roof of the building, followed by a few men, but found a private soldier had preceded me by some other way. There were still quite a number of Mexicans on the roof, among them a major and five or six officers of lower grades, who had not succeeded in getting away before our troops occupied the building. They still had their arms, while the soldier before mentioned was walking as sentry, guarding the prisoners he had surrounded, all by himself. I halted the sentinel, received the swords from the commissioned officers, and proceeded, with the assistance of the soldiers now with me, to disable the muskets by striking them against the edge of the wall, and throw them to the ground below.
Molino del Rey was now captured, and the troops engaged, with the exception of an appropriate guard over the captured position and property, were marched back to their quarters in Tacubaya. The engagement did not last many minutes, but the killed and wounded were numerous for the number of troops engaged.
During the night of the 11th batteries were established which could play upon the fortifications of Chapultepec. The bombardment commenced early on the morning of the 12th, but there was no further engagement during this day than that of the artillery. General Scott assigned the capture of Chapultepec to General Pillow, but did not leave the details to his judgment. Two assaulting columns, two hundred and fifty men each, composed of volunteers for the occasion, were formed. They were commanded by Captains McKinzie and Casey respectively. The assault was successful, but bloody.
In later years, if not at the time, the battles of Molino del Rey and Chapultepec have seemed to me to have been wholly unnecessary. When the assaults upon the garitas of San Cosme and Belen were determined upon, the road running east to the former gate could have been reached easily, without an engagement, by moving along south of the Mills until west of them sufficiently far to be out of range, thence north to the road above mentioned; or, if desirable to keep the two attacking columns nearer together, the troops could have been turned east so as to come on the aqueduct road out of range of the guns from Chapultepec. In like manner, the troops designated to act against Belen could have kept east of Chapultepec, out of range, and come on to the aqueduct, also out of range of Chapultepec. Molino del Rey and Chapultepec would both have been necessarily evacuated if this course had been pursued, for they would have been turned.