Smith, George B. McClellan, and J. G. Foster, of the corps of engineers, all officers who attained rank and fame, on one side or the other, in the great conflict for the preservation of the unity of the nation. The reconnoissance was completed, and the labor of cutting out and making roads by the flank of the enemy was effected by the 17th of the month. This was accomplished without the knowledge of Santa Anna or his army, and over ground where he supposed it impossible. On the same day General Scott issued his order for the attack on the 18th.
The attack was made as ordered, and perhaps there was not a battle of the Mexican war, or of any other, where orders issued before an engagement were nearer being a correct report of what afterwards took place. Under the supervision of the engineers, roadways had been opened over chasms to the right where the walls were so steep that men could barely climb them. Animals could not. These had been opened under cover of night, without attracting the notice of the enemy. The engineers, who had directed the opening, led the way and the troops followed. Artillery was let down the steep slopes by hand, the men engaged attaching a strong rope to the rear axle and letting the guns down, a piece at a time, while the men at the ropes kept their ground on top, paying out gradually, while a few at the front directed the course of the piece. In
