456 COMMERCIAL DESCKIPTION OF of wlilch are carefully lined with the bark of the larfj^e forest-trees of the neii^hbourhood. Into this trench the ore previously accumulated on its bank is gradually thrown in, while a rapid stream of water is made to pass through it, the labourer ao^itatinjj the materials with a hoe. The earth and sand are carried off by the water. The ore and large stones by their gravity subside, when the lat- ter are separated from the former by manual la- bour, with the occasional use of sieves. The purified ore thus obtained is removed to sheds erected for the purpose, and which contain the furnaces and apparatus for smelting. The process of smelting is usually performed once a- year, or, in a very productive season, twice. The furnace is ten feet long, four wide, and composed of clay. The bellows, or ventilator, is a piece of timber, about twenty-five inches in diameter, hav- ing; a bore of seventeen or eigrhteen inches admit- ting a piston. It is made of a single tree, and its fabrication requires considerable skill. This en- gine, plied by three stout workmen, keeps up a constant blast on the furnace. A quantity of ignit- ed charcoal is first thrown into the furnace, which continues, as long as the process of smelting goes forward, to be fed alternutely with ore and coals. In due time, and wjien the furnace is heated, the metal begins to flow, in a full stream, from an aperture for the purpose in the bottom of the floor,