Page:Archaeological Journal, Volume 5.djvu/41

Rh from the furnace. Each "pila" is formed of twelve "laterculæ bessales," with loam or fine mortar between them, and two capping tiles, one about 11 in. square and the other about 12 in., all 1 in. thick, so that by extending the top of the pila in form of a capital, better support is given to the "tegulæ bipedales," or tiles of 2 ft., which thus obtained a good bearing on the pilæ, four tiles met in the centre of each pillar with the flanged edges upwards, (see drawing A,) these being imbedded in the super-incumbent stratum of concrete 4 in. thick, formed a solid surface to receive the decorated mosaic floor, and one which in its materials formed a strong conductor of heat. The mosaics here are wanting. The situation and measurement of these parts were ascertained by a workman creeping in amongst them.

The floor on which the pilæ rest has not been bored through, but it is of concrete, with many of the sesquipedales tegulæ or tiles of 1 ft.; it inclines slightly to the east, on the centre of which side behind two of the pilæ projects a triangular mass of brick- work, 3 ft. on each side, with the eastern point cut off to about 1 ft. in width, thus forming two narrow passages or flues 15 in. in width, and communicating with a wider passage which extends beyond it, the roof supported by pilæ of similar construction to those in the hypocaustum, the passage is about 3 ft. wide and 2 ft. high, the first pilæ is almost close to the blunt end of the triangle, then occurs a space of 14 in., then a second pila followed by