BOOK XII.

579

Pots having spouts.

Pots without spouts.

Lids.

which hold two of these pots, are divided into three parts ; the lowest part is afoot high, and has an opening at the front for the draught; the top of this iscovered with iron plates, which are perforated near the edges, and thesesupport iron rods, upon which the firewood is placed. The middle part of thefurnace is one and a half feet high, and has a mouth in front, so that the woodmay be inserted ; the top of this has rods, upon which the bottom of the potsstand. The upper part is about two feet high, and the pots are also two feethigh and one digit thick ; these have below their mouths a long, slender spout.In order that the mouth of the pot may be covered, an earthenware lid ismade which fits into it. For every two of these pots there must be one pot

like product. The equipment described for pyrites in the next paragraph would be obviouslyuseful only for coarse material.

But little can be said on the history of sulphur ; it is mentioned often enough in the Bibleand also by Homer (Od. xxii., 481). The Greeks apparently knew how to refine it, althoughneither Dioscorides nor Pliny specifically describes such an operation. Agricola says (DeNat. Fos., 220): “ Sulphur is of two kinds ; the mineral, which the Latins call vivum, andthe Greeks apyron, which means ‘ not exposed to the fire ’ ( ignem non expertum) asrightly interpreted by Celsius ; and the artificial, called by the Greeks pepyromenon, thatis, ‘ exposed to the fire.’ ” In Book X., the expression sulfur ignem non expertum frequentlyappears, no doubt in Agricola’s mind for native sulphur, although it is quite possible thatthe Greek distinction was between “ flowers ” of sulphur and the “ wax-like ” variety.