What wonder if this Spanish soldier went crazy at the astounding wealth set out at his feet! What wonder that he forgot the siege of Mexico, forgot in this supreme moment all his caution, the scheming and the cunning which he had been so careful to practise. All through he had thrown dust in the eyes of his comrades, just as he had deceived the English aboard the brigantine. Not once in his waking conscious moments had he let fall a syllable of his great secret. He had waited, silent and watchful, for the end of the siege, and only once had his caution been relaxed. He had been tried, and the native pulque pleased his palate. He had drunk deeply, and, roused by the potent drink, had whispered something which had aroused a suspicion, for it is only dead men who tell no tales. Alvarez in his cups was a live man, robbed of caution for the moment, and that moment was destined to be his ruin; for, outside, creeping up the stairway of the tower, came a Spaniard, that one who had overheard his drunken words. He followed his comrade, having gained news of his whereabouts. But he knew nothing of Roger, though, in a little while, when he rounded the next curve, and ascended a few more steps, the figure of the crouching giant would come into view. Tap! Something fell on the tiled pavement on the summit of the tower, and Roger raised his head and started at the sound. His head shot up above the vase, and he peeped out. "A crossbow bolt here!" he said to himself in astonishment. "And it is of our own manufacture. I can tell that by the bright colour of the feathers." The sight caused him to think, and, for the moment, led his thoughts away from the task he had in hand. He pondered, but famine had dulled his wits. He was too weak to look further into a matter which could not be of importance, and he was therefore in the act of crouching again when a second bolt fell at his feet. "A second! Then it must be a signal. Who can have fired it?" He was at once alert, conscious that danger threatened from some unknown quarter, and he promptly crept to the edge of the tower and looked over. There was a figure crouching in the garden bushes below, a figure which waved frantically to him. Then it started from its lair and staggered to the steps, gesticulating, pointing to the side of the tower. "Tamba!" exclaimed Roger. "The faithful fellow has shadowed me through the siege, and has followed here, and he sees something wrong. Some one may be following."