BOOK IX. 379 



of the bellows, and blows up the fire with the bellows ; thus within the space 

 of half an hour the forehearth, as well as the hearth, becomes warmed, and 

 of course more quickly if on the preceding day ores have been smelted in the 

 same furnace, but if not then it warms more slowly. If the hearth and 

 forehearth are not warmed before the ore to be smelted is thrown in, the furnace 

 is injured and the metals lost ; or if the powder from which both are made 

 is damp in summer or frozen in winter, they will be cracked, and, giving 

 out a sound like thunder, they will blow out the metals and other substances 

 with great peril to the workmen. After the furnace has been warmed, the 

 master throws in slags, and these, when melted, flow out through the tap- 

 hole into the forehearth. Then he closes up the tap-hole at once with 

 mixed lute and charcoal dust ; this plug he fastens with his hand to a 

 round wooden rammer that is five digits thick, two palms high, with a handle 

 three feet long. The smelter extracts the slags from the forehearth with a 

 hooked bar ; if the ore to be smelted is rich in gold or silver he puts into the 

 forehearth a centumpondium of lead, or half as much if the ore is poor, 

 because the former requires much lead, the latter little ; he immediately 

 throws burning firebrands on to the lead so that it melts. Afterward he 

 performs everything according to the usual manner and order, whereby he 

 first throws into the furnace as many cakes melted from pyrites 12 , as he 

 requires to smelt the ore ; then he puts in two wicker baskets full of ore 

 with litharge and hearth-lead 13 , and stones which fuse easily by fire of the 

 second order, all mixed together ; then one wicker basket full of charcoal, 

 and lastly the slags. The furnace now being filled with all the things I 

 have mentioned, the ore is slowly smelted ; he does not put too much of it 

 against the back wall of the furnace, lest sows should form around the nozzles 

 of the bellows and the blast be impeded and the fire burn less fiercely. 



This, indeed, is the custom of many most excellent smelters, who know 

 how to govern the four elements 14 . They combine in right proportion the 

 ores, which are part earth, placing no more than is suitable in the furnaces ; 

 they pour in the needful quantity of water ; they moderate with skill the air 

 from the bellows ; they throw the ore into that part of the fire which burns 

 fiercely. The master sprinkles water into each part of the furnace to dampen 

 the charcoal slightly, so that the minute parts of ore may adhere to it, 

 which otherwise the blast of the bellows and the force of the fire would agitate 

 and blow away with the fumes. But as the nature of the ores to be smelted 

 varies, the smelters have to arrange the hearth now high, now low, and to 

 place the pipe in which the nozzles of the bellows are inserted sometimes on a 

 great and sometimes at a slight angle, so that the blast of the bellows may 



12 Panes ex pyrite conflali. While the term matte would cover most cases where this 

 expression appears, and in many cases would be more expressive to the modern reader, yet 

 there are instances where the expression as it stands indicates its particular origin, and it 

 has been, therefore., considered advisable to adhere to the literal rendering. 



ia Molybdaena. See note 37, p. 476. It was the saturated furnace bottoms from 

 cupellation. 



14 The four elements were earth, air, fire, and water. 



