firm enough to allow the growth of small trees, and to sustain a hut for the residence of the person that had charge of it, who with a long pole, resting on the sides or the bottom of the shallow basin, could change the position of his little territory at pleasure, which with its rich freight of vegetable stores was seen moving like some enchanted island over the water.4
The ancient dikes were three in number. That of Iztapalapan, by which the Spaniards entered, approaching the city from the south. That of Tepejacac, on the north, which, continuing the principal street, might be regarded, also, as a continuation of the first causeway. Lastly, the dike of Tlacopan, connecting the island-city with the continent on the west. This last causeway, memorable for the disastrous retreat of the Spaniards, was about two miles in length. They were all built in the same substantial manner, of lime and stone, were defended by draw-bridges, and were wide enough for ten or twelve horsemen to ride abreast.5
The rude founders of Tenochtitlan built their frail tenements of reeds and rushes on the group of small islands in the western part of the lake. In process of time, these were supplanted by more substantial buildings. A quarry in the neighborhood, of a red porous amygdaloid, tetzontli, was opened, and a light, brittle stone drawn from it and wrought with little difficulty. Of this their edifices were constructed, with some reference to architectural solidity, if not elegance. Mexico, as already noticed, was the residence of the great chiefs, whom the sovereign encouraged, or rather compelled, from obvious motives of policy, to spend part of the year in the capital. It was also the temporary abode of the great lords of Tezcuco and Tlacopan, who shared, nominally at least, the sovereignty of the empire.6 The mansions of these dignitaries, and of the principal nobles, were on a scale of rude magnificence corresponding with their state. They were low, indeed,—seldom of more than one floor, never exceeding two. But they spread over a wide extent of ground, were arranged in a quadrangular form, with a court in the centre, and were surrounded by porticoes