THE SIEGE BEGINS
common malefactor. To Tlascala a message was sent informing the elders of the republic that among the Spaniards desertion was always punished with death.
Success seemed ever to wait on the ruthless white men. Alvarado at Tacuba broke down the aqueduct which carried fresh water to Mexico from cypress-crowned Chapoltepec. Sandoval captured Iztapalapan. Cortés with the brigantines waited grimly for the swarm of Aztec canoes which sallied forth from the city on battle intent. Like gnats they gathered round the warships. At this moment a breeze arose, and the Spanish fleet moving forward crashed into the light canoes, breaking and sinking them in every direction, while over the waters far and wide the guns spread havoc and death. The rout was complete. The brigantines, from this time masters of the lake, proved, as Cortés himself said, "the key of the war."
With the aid of the fleet it was easy work to capture the Fort of Xoloc, and at that important point Cortés made his camp. In vain did the Aztecs, fighting day and night, make desperate efforts to retrieve their mistake in leaving such a post so weakly garrisoned. Breaking up a small piece of the causeway, Cortés made a channel for his ships, and the Aztecs, riddled on either side by the terrible guns, were driven back to the city in head-long flight.
The Spaniards held the western causeway of Tacuba, the great southern avenue of Iztapalapan with its branch to Cojohuacan, and now Sandoval
