Cortes now decided to attack the city from three sides and divided his army into as many columns. Sandoval was given command of the first, Alvarado of the second, and Olid of the third. The first was to advance from Tezcuco, the second from Tacuba, and the third from Kajahuakan, while Cortes himself, commanding the vessels, was to support them. The three took the positions assigned them and began the advance. Alvarado and Olid on their march destroyed the fine aqueducts which brought the sweet mountain water from many miles away into the island city. The water famine which followed was only the beginning of the many hardships with which the unfortunate people had to contend. From this time on, not a day passed without some fierce encounter. The vessels had to attack a vast swarm of small canoes and the land troops an equally vast swarm of the enemy at the causeways. The frail canoes were soon destroyed or driven ashore, however, but in the encounters at the causeways little was achieved. The Spaniards attacked with the utmost vigor the bulwarks erected to protect the openings, but every night they were forced to retire to the mainland, while the besieged every night restored what they had lost during the day. Notwithstanding all this bloodshed, they made no progress from day to day, and the fatigue of the Spaniards and their allies each day was so great that they began to fear they would gradually succumb. Chapter XV The Spaniards Lose Heavily in Battle—The Prisoners are Sacrificed—Some of Cortes’ Allies Desert but Soon Return—The City of Mexico Captured—Guatemozin Attempts Flight but is Taken Cortes, realizing that the battle could not be continued in this wise, decided to end the long and wearisome struggle with one bold venture. He arranged for a general attack at a designated time (this was about the end of May, 1521) and ordered each of his commanders to advance into the city with his division, in spite of all obstacles, and post himself there. He himself took command of the force which was to attack the causeway of Cojohuacan, determined to let nothing stop him from reaching the city. The eventful day came. The leaders placed themselves at the head of their troops and the tragedy began. It was a thrilling spectacle, the irresistible advance of the Spaniards and the stubborn resistance of the Mexicans. Nothing could withstand the onset of Cortes. He carried one defence after the other in desperate charges, cut down or shot down everything before him, and pursued the flying enemy into the city.