During the short conversation between the Comandante and Roblado he had not been idle, though apparently so. He had made a full reconnaissance of the walls. He saw that out of the saguan, or gateway, an escalera of stone steps led up to the azotea. This communication was intended for the soldiers, when any duty required them to mount to the roof; but Carlos knew that there was another escalera, by which the officers ascended: and although he had never been inside the Presidio, he rightly conjectured that this was at the adjacent end of the building. He had observed, too, that but one sentry was posted at the gate, and that the stone banquette, inside the saguan, used as a lounging-place by the guard, was at the moment unoccupied. The guard were either inside the house, or had strayed away to their quarters. In fact, the discipline of the place was of the loosest kind. Vizcarra, though a dandy himself, was no martinet with his men. His time was too much taken up with his own pleasures to allow him to care for aught else. All these points had passed under the keen observation of the cibolero before Vizcarra returned to announce his intention of sending the troop. He had scarce parted out of sight the second time ere the former had taken his measures. Silently dismounting from his horse, Carlos left the animal standing where he had halted him. He did not fasten him to either rail or post, but simply hooked the bridle-rein over the "horn" of the saddle. He know that his well-trained steed would await him there. His rifle he still carried under his serape, though the butt was now visible below the edge, pressed closely against the calf of his leg. In this way he walked forward to the gate. One doubt troubled him--would the sentry permit him to pass in? If not, the sentry must die! This resolve was quickly made; and the cibolero under his serape kept his grasp on the handle of his hunting-knife as he approached the gate. The attempt was made to pass through. Fortunately for Carlos, and for the sentry as well, it was successful. The latter--a slouching, careless fellow--had heard the late conversation, and had no suspicion of the other's design. He made some feeble opposition, notwithstanding; but Carlos hastily replied that he had something to say to the Comandante, who had beckoned him up to the azotea. This but half satisfied the fellow, who, however, reluctantly allowed him to pass. Once inside, Carlos sprang to the steps, and glided up with the stealthy silent tread of a cat. So little noise had his moccasins made upon the stones, that, when he arrived upon the roof, its occupant--although standing but six feet from the head of the escalera--was not aware of his presence!