588 BOOK XII.

feet, and of the mouth and bottom one foot. In the back part of the furnaceis a rectangular hole, measuring in height and width a palm, through whichthe heat penetrates into a third furnace which adjoins it.

This third furnace is rectangular, eight feet long and six feet wide ; italso consists of two chambers, of which the lower has a mouth in front, so thatfirewood may be placed on the hearth which is on the ground. On each side ofthis opening in the wall of the lower chamber is a recess for oblong earthen-ware receptacles, which are about four feet long, two feet high, and one anda half feet wide. The upper chamber has two holes, one on the right side,the other on the left, of such height and width that earthenware receptaclesmay be conveniently placed in them. These latter receptacles are threefeet long, one and a half feet high, the lower part one foot wide, and theupper part rounded. In these receptacles the glass articles, which have beenblown, are placed so that they may cool in a milder temperature ; if they werenot cooled slowly they would burst asunder. When the vessels are takenfrom the upper chamber, they are immediately placed in the receptaclesto cool.

Sin

A —Arches of the second furnace. B—Mouth of the lower chamber.C —Windows of the upper chamber. D —Big-bellied pots. E—Mouth of the

THIRD FURNACE. F—RECESSES FOR THE RECEPTACLES. G-OPENINGS IN THE UPPER

chamber. H —Oblong receptacles.