CHAP. 36.—PHRYGIAN STONE.
Phrygian stone is so called from the country which produces it, and is a porous mass like pumice. It is first saturated with wine, and then calcined, the fire being kept up with the bellows till the stone is brought to a red heat; which done, it is quenched in sweet wine. This operation is repeated three times. The only use made of it is for dyeing cloths.[2715]