While the struggle was raging thus fiercely from January 28 to February 1, in the eastern area of street-fighting, there had been a no less desperate series of combats all around Santa Engracia, on the southern front of attack. Here Musnier’s division was endeavouring to drive the Spaniards out of the blocks of houses to the right and left of the captured convent. They worked almost entirely by mines, running tunnels forward from beneath the convent to blow down the walls of the adjoining dwellings. But even when the mines had gutted the doomed buildings, it was not easy to seize them: the few men who survived the explosion did not fly, but held out among the ruins, and had to be bayonetted by the assailants who rushed out from the convent to occupy the new lodgements. Time after time the defenders, though perfectly conscious that they were being undermined, and that by staying on guard they were courting certain death, refused to evacuate the threatened houses or to retire into safety. Hence their losses were awful, but the French too suffered not a little, while pushing forward to occupy each building as it was cleared by the explosion. The constant rain of musket balls from roofs and church towers searched out the ruins in which they had to effect their lodgements, and many of the assailants fell before they could cover themselves among the débris. On the thirty-first the Spaniards made a sudden rush from the Misericordia buildings, to recover the Trinitarian convent, the most western point on the _enceinte_ which had fallen into the hands of the French at the assault of the twenty-seventh. They charged in upon it with the greatest fury, and blew open the gate with a four-pounder gun which they dragged up by hand to the very threshold. But the French had built up the whole entrance with sandbags, which held even when the doors had been shattered; and, after persisting for some time in a fruitless attempt to break in, the Saragossans had to retire, foiled and greatly thinned in numbers.