arms so long as there was a Spaniard left on whom to use them.9 The evident desire of the besieged for peace served only to encourage the Indians, and the assault was renewed with an increased ardor that taxed the defenders to the utmost.
And now, whatever the cost, a way out of this place must be opened. Cortés knew of three causeways which led to the mainland, the only means of exit for his forces. He knew that they were low and narrow, exposed on both sides to the attacks of canoe fleets, and intersected by a number of bridges which were perhaps by this time raised. Each of these openings was an almost impassable chasm. The southern causeway to Iztapalapan was two leagues in length, and provided with seven drawbridges, besides a strong fortress, which rendered it impassable to an enemy. The northern, leading to Tepeyacac, was one league long, while the shortest, conducting westward to Tlacopan, half a league distant, was broken by only three bridges.10 Cortés resolved to undertake the passage by this last named causeway. During the night had been completed three mantas, of light framework and planks, each to hold twenty musketeers and archers, with which it was hoped to check the assailants on the roofs. These mantas were built with two chambers, provided with loop-holes; the upper ranged on a level with the house-tops of ordinary one-story buildings of the city, and had doors, so as to allow of sallies upon the roofs.11
The following morning, June 28th, Cortés placed himself at the head of five hundred Spaniards and over three thousand allies, and took the direction of the Tlacopan causeway.12 By a sudden charge the cavalry drove back the Indians and allowed the free passage of the mantas, which were drawn and pushed by Tlascaltecs, and protected by bodies of infantry. A corps of pioneers accompanied them with pickaxes, mattocks, crow-bars, and ladders, to