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 like manner the guns were drawn by hand up the opposite slopes.

In this way Scott's troops reached their assigned position in rear of most of the intrenchments of the enemy, unobserved.
The attack was made, the Mexican reserves behind the works beat a hasty retreat, and those occupying them surrendered.