Trov. igg metres in length by forty-five centimetres in width, and from ten to fifteen centimetres in depth. These bricks were bonded with clay of somewhat different quality from that of the squares ; its colour is lighter, and the straw mixed in it chopped up much finer. The joints between the stones have a mean width of three to four centimetres (Fig. 51). They were covered with a thin coating of white clay.' Here and there on these walls, at a distance of four metres from each other, appear transverse poles, which run far out into the depth of the wall ; whilst some of the bricks are seamed from top to bottom by grooves, rendered very shallow by the disintegration of the outward sur- ^^^ -n^JlitA VXi^V showing ground-sill and sockets of wood a face. Around these cavities, half filled with ashes and charcoal, the bricks have been burnt to a dark red. Traces of smoke are visible for a short distance, then farther away from these orifices the desiccated brick resumes its normal aspect. Numbers of squares, whether found away from the holes or in the lower courses of the wall, bear no mark of the action of the fire, ^ A small sea-shell, cardium edule, abounding in the waters close by, is found in large quantities in these bricks. Virchow thinks them due to kitchen refuse, the shells having been thrown away after the mollusk which they contained had been eaten : ihey thus got mixed with the earth of which the bricks were made. The clay contains many other impurities, bits of old pottery, bones, etc.
