AMALGAMATING ?flACHINERY.—X. P. Boss's Special used for grinding the pulp as it comes fi.om the battery in the Boss continuous process. is a solid, shallow cast-iron pan, 4 ft. in diameter, having solid ring shoes and dies slotted for a short distance from their inner edges to better admit the pulp between them. The pulp is introduced at the center of the pan; and, as a joint is made with a rubber gasket between the shoe-ring and muller plate, it is all obliged to pass between the shoe and die before being discharged.
AL P. Boss's Standard Amalgamating Pan, (Figs. 4 and 5) is similar to the pans used in the Washoe process, but is made rather heavier, and is provided with a wearing ring inside of staves, and also with a sleeve for the protecting cone. The steam bottom extends up into and around the cone, and at its top carries the bearing for the pan-spindle. By this arrangement a greatly increased heating surface is obtained. A rust joint is made between the cone on the steam bottom and the main-pan cone, while the steam bottom proper is bolted to the pan bottom in the usual manner. Exhaust steam is used for heating, the steam being admitted on one side of the bottom and exhausted at the other, a valve being provided for regulating or shutting off. The pan-spindle step is carried on a bracket cast on the main driving shaft box, and permits the removal of the shaft without disturbing spindle. The friction-ring through which the pan is driven is bolted to the gear, so that it can at any time be replaced independently of the other parts when worn or broken. In front of the pan is a quicksilver bowl with a pan siphon for draining the pan of quicksilver and pulp when in need of repairs, These pans are 5 ft. 2 in. in diameter (inside), and weigh 8,500 lbs.
..1/. P. Boss's Standard Seller is a cast-iron pan, 8 ft. in diameter, with muller arms and
driver cast in one piece, to which the muller-plate is bolted. The friction-gear and arrange ment of spindle-step are the same as in the pans. The shoes are worked close to the bottom lad do not touch it, and, on account of the angle at which they are placed, form a strong under-current which sweeps the bottom, thus saving wear and tear. Quicksilver bowls are provided the same as for pans, and to which siphon can he applied for draining. The settlers are fitted with heavy wrought-iron sides, and are connected together near their tops in a simi lar manner to the pans. The cone is cast with the settler-bottom, and is made very wide at its base with the shoes working close up to it, thus preventing the accumulation of settled pulp on the bottom with the clogging and breakage that is liable to ensue. The entire surface of the bottom between the base of the cone and outer groove is swept by the shoes.
X. P. Boss's Bullion-Melting Furnace, for melting the silver bullion from the retorts, is similar to an ordinary forge, consisting of a cylindrical pan with a hemispherical bottom, lined with 2 in. of fire-clay and bone-ash mixed. The back of the furnace has a water-jacket through which pass two tures At the bottom of the pan is a discharge-spout, stopped with a bone-ash plug, through which the bullion is drawn off into molds. The furnace is filled with charcoal, air is blown through the tuyilres by means of a bellows, bullion fed in, incited, and drawn off into molds. It is claimed that this furnace has an advantage over the reverbera tory style in melting by a reducing flame instead of an oxidizing, thus avoiding the loss of silver by oxidation.