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BOOK VIII.

These pieces of metal are afterward heated in iron basins and smelted in thecupellation furnace by the smelters.

Although the miners, in the shafts or tunnels, have sorted over thematerial which they mine, still the ore which has been broken down and carriedout must be broken into pieces by a hammer or minutely crushed, so thatthe more valuable and better parts can be distinguished from the inferior andworthless portions. This is of the greatest importance in smelting ore, forif the ore is smelted without this separation, the valuable part frequentlyreceives great damage before the worthless part melts in the fire, or else theone consumes the other; this latter difficulty can, however, be partlyavoided by the exercise of care and partly by the use of fluxes. Now, if avein is of poor quality, the better portions which have been broken down andcarried out should be thrown together in one place, and the inferior portionand 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 tothe edge of the sides and back are fixed upright planks, which rise about afoot from the table ; the front, where the sorter sits, is left open. The

A— Tables. B— Upright planks. C— Hammer. D— Quadrangular hammer.E—Deeper vessel. F—Shallower vessel. G —Iron rod.