The Americans now advanced to attack the strong defences of the capital. By General Scott’s plan, General Twiggs kept up a heavy fire upon the southern part of the city, to divert the attention of the enemy, while General Worth advanced to attack the San Cosmo gate, and General Quitman the Belen gate. The troops of these divisions were exposed to a tremendous and destructive fire from batteries placed along the roads and at the gates. But the men now seemed insensible to danger, and pressed on with a valor that never was surpassed. Many valuable officers fell at their head, and this excited a spirit of revenge among the troops, which led them to give but little quarter to the enemy. By night-fall, both gates were carried, and the conquerors had gained a foothold in the city. The next morning, while General Scott was preparing to complete the work, the government surrendered. The Mexican army had fled from the city. On the 14th of September, the Americans entered Mexico in triumph. [Illustration] [Illustration: ATTACK AT THE NATIONAL BRIDGE.] DEFEAT OF THE MEXICANS AT THE NATIONAL BRIDGE. The first affair in which General Cadwalader distinguished himself in Mexico was a skirmish at the National Bridge, during his march to join Scott at Puebla. Colonel M’Intosh had started with a train for the interior; but being attacked by an overpowering force of the enemy, had been forced to await the arrival of Cadwalader, who, hearing of his danger, hurried up, with eight hundred men to his succor. On approaching the National Bridge, Cadwalader, at the head of the united forces, seized some heights which the enemy had previously occupied. He was here attacked by a strong force, but made good his defence, charging the Mexicans incessantly, until their strength was broken, when the bridge was passed in safety. In this action the foe lost one hundred in killed and wounded: Cadwalader about fifty. This victory was won principally by artillery, a species of force with which Cadwalader was perfectly familiar. [Illustration] [Illustration: GENERAL PIERCE, ENTERING PUEBLA.] GENERAL PIERCE.