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BOOK IX 



described above, is drawn backward and forward upon narrow boards of 

 equal length placed over a long box ; the powder which falls through the 

 sieve into the box is suitable for the mixture ; the lumps that remain in the 

 sieve are thrown away by some people, but by others they are placed under 

 the stamps. This powdered earth is mixed with powdered charcoal, moist- 

 ened, and thrown into a pit, and in order that it may remain good for a long 

 time, the pit is covered up with boards so that the mixture may not 

 become contaminated. 



They take two parts of pulverised charcoal and one part of powdered 

 earth, and mix them well together with a rake ; the mixture is moistened by 

 pouring water over it so that it may easily be made into shapes resembling 

 snowballs ; if the powder be light it is moistened with more water, if heavy 

 with less. The interior of the new furnace is lined with lute, so that the 

 cracks in the walls, if there are any, may be filled up, but especially in order 

 to preserve the rock from injury by fire. In old furnaces in which ore has 

 been melted, as soon as the rocks have cooled the assistant chips away, with 

 a spatula, the accretions which adhere to the walls, and then breaks them 

 up with an iron hoe or a rake with five teeth. The cracks of the furnace are 

 first filled in with fragments of rock or brick, which he does by passing his 

 hand into the furnace through its mouth, or else, having placed a ladder against 

 it, he mounts by the rungs to the upper open part of the furnace. To the 

 upper part of the ladder a board is fastened that he may lean and recline 

 against it. Then standing on the same ladder, with a wooden spatula, he 

 smears the furnace walls over with lute ; this spatula is four feet long, a digit 

 thick, and for a foot upward from the bottom it is a palm wide, or even 

 wider, generally two and a half digits. He spreads the lute equally over the 

 inner walls of the furnace. The mouth of the copper pipe 9 should not pro- 

 trude from the lute, lest sows 10 form round about it and thus impede the 

 melting, for the furnace bellows could not force a blast through them. Then 

 the same assistant throws a little powdered charcoal into the pit of the fore- 

 hearth and sprinkles it with pulverised earth. Afterward, with a bucket 

 he pours water into it and sweeps this all over the forehearth pit, and with the 

 broom drives the turbid water into the furnace hearth and likewise sweeps 

 it out. Next he throws the mixed and moistened powder into the furnace, 

 and then a second time mounting the steps of the ladder, he introduces the 

 rammer into the furnace and pounds the powder so that the hearth is made 

 solid. The rammer is rounded and three palms long ; at the bottom it is five 

 digits in diameter, at the top three and a half, therefore it is made in the form 

 of a truncated cone ; the handle of the rammer is round and five feet long and 



9 It has not been considered necessary to introduce the modern term twyer in these des- 

 criptions, as the literal rendering is sufficiently clear. 



l Ferruminala. These accretions are practically always near the hearth, and would 

 correspond to English " sows," and therefore that term has been adopted. It will be noted 

 that, like most modern metallurgists, Agricola offers no method for treating them. Pliny 

 (xxxiv, 37) describes a " sow," and uses the verb ferruminare (to weld or solder) : " Some 

 " say that in the furnace there are certain masses of stone which become soldered together, 

 " and that the copper fuses around it, the mass not becoming liquid unless it is transferred 

 " to another furnace ; it thus forms a sort of knot, as it were, of the metal." 



