CHAPTER XVIII.
IN THE AZTEC STRONGHOLD.
[A. D. 1519.] The city of Mexico, built on an island in Lake Tezcoco, was connected with the mainland by four causeways of stone. That by which Cortez approached, six miles in length, commenced at Mexicalcingo, and, crossing the lake to the island, was prolonged on the north to Tepeyacac, where is now the shrine of Guadalupe; another ran nearly west, and the fourth, which supported an aqueduct, terminated at Chapultepec. All centred in the great square of the city, from which branched other streets and canals, or streets one-half water and the other half solid earth. All these causeways were intersected by broad ditches to allow passage to the water of the lake, crossed by wooden bridges that could be easily raised, and thus cut off the retreat of an enemy brave enough to advance over them.
The grand causeway was eight yards wide, and ran straight to Mexico. In good order, the Spaniards marched over it between the assembled thousands of Indians. At about a mile from the city this causeway was joined by another from the town of Coyoacan, and at their juncture was a small, though strong, fortress, with walls ten feet high, battlements, two entrances, and a drawbridge. This point was called Xoloc, and was occupied by Cortez in the following year as his military headquarters, whence he directed the siege of the city. The army halted here, and waited, until more than a thousand Mexican nobles had
