Finding that he could not oppose himself to our soldiers, who were all posted out of sight, and that he was losing his men rapidly, General bcott took possession of the convent of San Isidor. which extends back to the centre of a block, and at once set his sappers and miners to cutting a way directly through the blocks of buildings. In some instances whole houses were blown up to facilitate his progress; but after several hours he again emer ged into the street, and finally regained the Plaza with grtat loss. On entering the Pl,za a heavy fire was opened on him from the Palace and Cathe dral.which were filled and covered with our patrio tic troops. Finding himself thus assaulted, the enemy drew out his forces in the Plaza, and opened a canonade on the Palace and Cathedral, finW over one hundred shots, which did immense damage to the buildings, and caused a severe loss of killed and wounded. Seeing further resistance useless, our soldiers ceased firing, and on the 15th September, (sad day 1) the enemy was in possession of the Mexican capital. Though we inflicted havoc and death upon tbe Yankees, we suffered greatly our eeives.-Many were killed by the blowing up of the

houses, many by the bombardment, Jut mora by the confusion which prevailed in the city ; *™ &n ° gether, we cannot count our killed, wounded, ana miming, since the action commenced yesterday ai I<-bs than 4,000. among whom are many women ana children. The enemy confessed a loss of over I ,oui». it is no doubt much greater. What a calamity I But Mexico will yet have vengeance, bod w v avenge us for our sufferings. Ahs ! that I should write this letter within sight of a proud enemy, *no has succeeded by his ferocity in trampling on our capital, and our country, An enemy who only prides himself upon shooting well with his rifle an<j cannon. But thus it is—we are prostrated—not humbled. We may be forced to silence, hut the first moment that presents us a chance will be de voted to terrible revenge. Santa Anna has gone with his generals and all the troops he could draw off to Guadeloupe. He is said to be wounded severely. We have lost heroic officers and bravo men in these two days. 