The column of the left, under the command of Brigadier-general Sir Samuel Auchmuty, advanced upon the northern quarter of the city. The 38th regiment, under the command of Colonel Nugent, at the extreme left of the line, made a considerable detour through the suburbs, and then advanced by a narrow road straight upon the Plaza del Retiro. Here the garrison was strongly posted in the barracks and the bull-ring, with cannon planted upon the open ground, and a large, flat-roofed house in front was occupied as an outpost. From this house a heavy fire was directed upon the regiment, causing severe loss; but it was captured by the bayonet, not one of the garrison escaping. Colonel Nugent then attempted to advance upon the bull-ring, but was repulsed by a murderous fire of artillery, upon which he detached two companies to take possession of a house on the high ground overlooking the river, to the north of the Retiro barracks. This operation was successful, and the two companies leaving the house by a side door forced their way into the barracks, drove out the garrison at the point of the bayonet and captured several cannon, all of which but one twelve-pounder were spiked. Colonel Nugent then hoisted his colours on the flag-staff, and opened fire with the captured gun upon the bull-ring. Meantime Sir Samuel Auchmuty had advanced with the 87th regiment by the Calles Arenales and Santa Fé, thinking that they would lead him to the left flank of the enemy's position on the Plaza del Retiro; instead of which, after a march of more than two miles, he found himself directly in front of their position, and was received by a tremendous fire of artillery and musketry from the bull-ring, against which it was impossible to advance. He accordingly retreated two squares to the right, where the little river Tercero, which flows down the Calle Paraguay, had scooped out a sort of trench, along which he marched his regiment, sheltered from the fire of the enemy, and took possession of a large house and garden on the high ground overlooking the river. Then hearing of the success of Colonel Nugent, he advanced to his support, and at half-past nine, after two hours of incessant firing the garrison of the bull-ring hung out a white flag and surrendered at discretion. By this success the British column captured 700 prisoners, thirty-two guns, most of them of large calibre, two mortars, and an immense quantity of ammunition, and secured at once a formidable base of attack, and the means of communicating with the squadron.