] The walls were generally of vast thickness, the chambers long and narrow, with the outer doors opening directly into them.

The rooms ordinarily led into one another, passages being rarely found.

Squared recesses, sometimes stepped or dentated, were common in the rooms; and in the arrangement of these something of symmetry is observable, as they frequently correspond to or face each other.

The roofs were probably either flat-beams of palm-wood being stretched across from wall to wall--or else arched with brick.

No indication of windows has been found as yet; but still it is thought that the chambers were lighted by them, only they were placed high, near the ceiling or roof, and thus do not appear in the existing ruins, which consists merely of the lower portion of walls, seldom exceeding the height of seven or eight feet.