482

BOOK X.

In certain places, as at Freiberg in Meissen, the upper part of thecupellation furnace is vaulted almost like an oven. This chamber is fourfeet high and has either two or three apertures, of which the first, infront, is one and a half feet high and a foot wide, and out of this flowsthe litharge ; the second aperture and likewise the third, if there be three,are at the sides, and are a foot and a half high and two and a half feet wide,in order that he who prepares the crucible may be able to creep into thefurnace. Its circular bed is made of cement, it has two passages two feet highand one foot wide, for letting out the vapour, and these lead directly throughfrom one side to the other, so that the one passage crosses the other at rightangles, and thus four openings are to be seen ; these are covered at the topby rocks, wide, but only a palm thick. On these and on the other partsof the interior of the bed made of cement, is placed lute mixed with straw,to a depth of three digits, as it was placed over the sole and the plates ofcopper and the rocks of that other furnace. This, together with the ashes whichare thrown in, the master or the assistant, who, upon his knees, preparesthe crucible, tamps down with short wooden rammers and with malletslikewise made of wood.

A —Furnace similar to an oven. B —Passage C—Iron bars. D —Hole throughWHICH THE LITHARGE IS DRAWN OUT. E—CRUCIBLE WHICH LACKS A DOME. F—THICK

sticks. G —Bellows

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