This was the moment, however, when the centre was destined to be penetrated and broken--Ridgely, as has been stated, had been ordered to the road, and, after advancing cautiously for a short distance, he descried the enemy about four hundred yards in advance. Pressing onward until within perfect range of his guns he began to play upon the foe with deadly discharges. But the resolute Mexicans were not to be repulsed. Returning shot for shot, their grape surged through our battery in every direction, yet without repulsing the intrepid Ridgely, who, as soon as the opposing fire slackened, limbered up and moved rapidly forward, never unlimbering unless he perceived the enemy in front or found from the fire of their infantry that they still hung upon his flank. During this fierce advance into the jaws of the Mexican crescent, he frequently threw into it discharges of canister when not over one hundred yards from the opposing batteries and their support. After hammering the centre for some time with this iron hail, and keeping the wings of the Mexicans engaged with the other troops, a movement with dragoons was planned for the final onslaught. May, with his powerful corps, was directed to report to the general, and immediately received orders from Taylor to charge the enemy's battery. Thridding the mazes of the chapparal and of the road with his dense squadron he came up with Ridgely, and halting a moment while that gallant soldier poured a volley into the enemy, which was answered by a shower of rattling grape, he dashed at the head of his troopers, like lightning from the midst of the cloud of smoke, over the guns of the astonished Mexicans. As the dragoons rushed at full tilt, with gleaming swords, along the road, the artillerists leaped upon their pieces and cheered them on. The infantry in the chapparal took up the shout, and before the combined thunder of cannon, huzzas, and galloping cavalry had died away, May and his troopers had charged through the seven opposing pieces, and rose again on the heights in rear of the ravine. Graham, Winship and Plesanton led the movement on the left of the road, whilst the captain, with Inge, Stevens and Sackett, bore off to the right. But, after gaining the elevation, only six dragoons could be rallied, and with these May charged back upon the gunners who had regained their pieces, drove them off, and took prisoner the brave La Vega who stood to his unwavering artillery during the heat of the dreadful onslaught.