distance to the further side of the pedregal was nearly a mile, and, on emerging from the rocks, Colonel Riley crossed a ravine, at the bottom of which was a small stream. On ascending the opposite slope, he came upon the San Angel road, at the hacienda of Ensaldo, about fourteen hundred yards north of the Hill of Contreras. Passing another ravine, also the bed of one of the tributaries of the Churubusco, he gained a second slope or elevation, upon which was the hamlet of San Geronimo, or Contreras, four hundred yards west of the main road, and connected with it by a narrow lane. Beyond the village was a third ravine, to which he extended his line, for the purpose of sweeping through the hamlet, and driving back the enemy's cavalry, large bodies of which had been dispatched by General Valencia to check the attempt to gain his rear.
Repeated attempts were made by the enemy's lancers to force Colonel Riley to retire, but they were always repulsed with loss. Having driven them back upon their support, he sheltered his brigade, temporarily, from the fire of the Mexican guns, in a ravine south and west of San Geronimo. Upon the arrival of Generals Cadwalader and Smith, with their brigades and the 15th infantry, a heavy force of cavalry and infantry, supported by six pieces of artillery, — afterwards ascertained to consist of 12,000 men, commanded by Santa Anna in person, — were discovered advancing from San Angel, and occupying the slopes west of the road. Colonel Riley now joined the other corps, and General Smith, as the senior officer present, took command of the united force, at most, but 3,300 strong.
General Smith commenced making his dispositions for attacking the enemy's columns in the direction of San Angel; but the delay in the transmission of his
