buildings. These calpulli were afterward further subdivided into communities,-each living in houses large enough to contain a small army. The rush huts in time gave place to more substantial edifices, many of which were elegant in design and finish. In Montezuma's day a quarry of soft blood-red stone almost as porous as a sponge was discovered in the mountains near by, and many of the houses in the city were rebuilt of this with fine effect.
The city was regularly laid out, with wide, straight, clean streets radiating from the central teocallis, or house of the gods (a plan which was followed throughout Mexico), and numerous and beautiful squares. One of these, the principal market-place of the city, was surrounded by splendid corridors so smoothly paved that they were as slippery as ice. Like Venice, the city was veined with canals, along which the produce of the country was borne in numberless boats into its very centre.
A massive stone aqueduct brought an abundance of pure water from a large spring at Chapultepec, a few miles distant. Immense reservoirs cut out of solid rock, with steps leading down to the level of the water, still remain to show the substantial character of Aztec masonry and enterprise. Where the branch streams of this aqueduct crossed the canals they were widened and left open on top, so that the carriers who served out water to families could bring their canoes directly under these bridge-like reservoirs to be filled, the water being dipped out for them by a man stationed above.
The houses of the better class in Mexico were built of stone and were seldom over two stories in height; they covered a great deal of ground, having large courtyards in the centre. The roofs were flat and terraced, the walls
