Jack had resolved to lead the principal sortie in person, and he devoted special attention to the organization of his band. Ten of the men were ordered to carry bags of powder to blow up the French galleries into Tobar and Vallejo, if the sortie party were able to push home their charge. Another ten were given short ladders and mats to assist the rest across the barricade, which was of timber, some twelve feet in height, and studded at the top with sharp nails. It had been constructed so hastily, and with so little idea of the possibility of a sortie, that it formed almost as formidable an obstacle to the Spaniards as to the French. The sortie party beyond the Casa Vega was entrusted to Don Cristobal, the reserve to Pablo Quintanar, the chief of the guerrilleros. This man was very much dissatisfied with the post allotted him; he grumbled and protested that he deserved a more prominent part in the operations, but Jack had a vague distrust of the fellow, and somewhat curtly refused to alter his arrangements. All was now ready. In the chill foggy dawn the men waited at their several posts for the expected explosion. Sounds floated across the river from the French lines: the blare of bugles, the rat-tat of drums, occasionally the loud call of bustling officers. Jack began to wonder whether the French would wait until their galleries into Tobar and Vallejo were ready, and then spring the three mines simultaneously. But the anxious period of waiting was at length ended. About an hour after daybreak there was a dull roar; the whole district seemed to tremble; there was the crash of falling stones and timber, a cloud of smoke and dust from the Casa Vega, and with a shout the French rushed into the ruined building beyond, to make good their position there.