270 



BOOK VIII. 



These pieces of metal are afterward heated in iron basins and smelted in the 

 cupellation furnace by the smelters. 



Although the miners, in the shafts or tunnels, have sorted over the 

 material which they mine, still the ore which has been broken down and carried 

 out must be broken into pieces by a hammer or minutely crushed, so that 

 the more valuable and better parts can be distinguished from the inferior and 

 worthless portions. This is of the greatest importance in smelting ore, for 

 if the ore is smelted without this separation, the valuable part frequently 

 receives great damage before the worthless part melts in the fire, or else the 

 one consumes the other ; this latter difficulty can, however, be partly 

 avoided by the exercise of care and partly by the use of fluxes. Now, if a 

 vein is of poor quality, the better portions which have been broken down and 

 carried out should be thrown together in one place, and the inferior portion 

 and the rock thrown away. The sorters place a hard broad stone on a table ; 

 the tables are generally four feet square and made of joined planks, and to 

 the edge of the sides and back are fixed upright planks, which rise about a 

 foot from the table ; the front, where the sorter sits, is left open. The 



9iP 



A — Tables B — Upright planks. C — Hammer, D — Quadrangular hammer. 

 E — Deeper vessel. F — Shallower vessel. G — Iron rod. 



