456 BOOK X. 



ashes fall from the burnt wood, which is supported by iron rods, arranged to 

 form a grating. The middle chamber is two feet high, and the wood is pushed 

 in through its mouth. The wood ought to be oak, holmoak, or turkey-oak, 

 for from these the slow and lasting fire is made which is necessary for this 

 operation. The upper chamber is open at the top so that the pots, for which 

 it has the depth, may be put into it ; the floor of this chamber consists of iron 

 rods, so strong that they may bear the weight of the pots and the heat of the 

 fire ; they are sufficiently far apart that the fire may penetrate well and may 

 heat the pots. The pots are narrow at the bottom, so that the fire entering 

 into the space between them may heat them ; at the top the pots are wide, 

 so that they may touch and hold back the heat of the fire. The upper part 

 of the furnace is closed in with bricks not very thick, or with tiles and lute, 

 and two or three air-holes are left, through which the fumes and flames may 

 escape. 



The gold granules or leaves and the cement, alternately placed in the pots, 

 are heated by a gentle fire, gradually increasing for twenty-four hours, if the 

 furnace was heated for two hours before the full pots were stood in it, and if 

 this was not done, then for twenty-six hours. The fire should be increased 

 in such a manner that the pieces of gold and the cement, in which is the 

 potency to separate the silver and copper from the gold, may not melt, for in 

 this case the labour and cost will be spent in vain ; therefore, it is ample to 

 have the fire hot enough that the pots always remain red. After so many 

 hours all the burning wood should be drawn out of the furnace. Then the 

 refractory bricks or tiles are removed from the top of the furnace, and the 

 glowing pots are taken out with the tongs. The lids are removed, and 

 if there is time it is well to allow the gold to cool by itself, for then there is 

 less loss ; but if time cannot be spared for that operation, the pieces of gold 

 are immediately placed separately into a wooden or bronze vessel of water 

 and gradually quenched, lest the cement which absorbs the silver should 

 exhale it. The pieces of gold, and the cement adhering to them, when cooled 

 or quenched, are rolled with a little mallet so as to crush the lumps and free 

 the gold from the cement. Then they are sifted by a fine sieve, which is 

 placed over a bronze vessel ; in this manner the cement containing the 

 silver or the copper or both, falls from the sieve into the bronze vessel, and the 

 gold granules or leaves remain on it. The gold is placed in a vessel and 

 again rolled with the little mallet, so that it may be cleansed from the cement 

 which absorbs silver and copper. 



The particles of cement, which have dropped through the holes of the 

 sieve into the bronze vessel, are washed in a bowl, over a wooden tub, being 

 shaken about with the hands, so that the minute particles of gold which have 

 fallen through the sieve may be separated. These are again washed in a 

 httle vessel, with warm water, and scrubbed with a piece of wood or a twig 

 broom, that the moistened cement may be detached. Afterward all the gold 

 is again washed with warm water, and collected with a bristle brush, and should 

 be washed in a copper full of holes, under which is placed a little vessel. 

 Then it is necessary to put the gold on an iron plate, under which is a vessel, 



