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be deemed their equivalent, so that the ore under treatment shall first come in contact with the iron, which does not touch the zinc lining, and afterwards in contact with the zinc pieces, which must be in contact with the zinc plate, and also with the zinc plate forming the mercury wells. Both the iron and zinc dependent pieces are made removable, and have each a separate electrical connection, such connections being preferably of an equal length, which conduces to uniformity in the intensity of the electric current. In the upper portion of the metal bridges to which the zinc pieces are attached, mercury troughs are provided for the purpose of resilvering the zinc when it is required to do so, without removing the metal bridges. This is effected by means of small apertures communicating from the trough to the faces of the zinc pieces. Toany convenient part of the chute, it may be either attached or separate, I provide a suitable trough or troughs into which is discharged the tailings and any amalgam which may be separated from the apparatus by the moving ore. A dash-plate, for regulating the flow, is also provided, and a perforated pipe with water flowing therefrom, which serves to facilitate the discharge of the tailings and to prevent the trough being clogged or choked. The metal bridges both for the iron or zinc are insulated in any approved manner to insure safety to the attendant during the operation of working. Suitable clamping devices are provided to retain the metal bridges in position, and the circuit of the various wires forming the connections between the metal bridges and the primary source of electricity are kept in circuit by the usual key or switch, so that the apparatus is under the easy control of the attendant. Where my device is made in the form of a circular tray, this trough and perforated pipe may either be suspended beneath the outer lip of the tray or may form an integral part of it, the pipe being placed in any suitable position. My invention is illustrated in the accompanying drawings, in which similar letters are used throughout the different views to indicate similar parts, and in which Fig. 1 is a plan of my invention in the form of a chute or conveyer; Fig. 2 is a longitudinal section taken on line α-a of Fig. 1; Fig. 3is a transverse section taken on line b-b of Fig. 1; Fig. 4is a transverse section taken on line c-o of Fig. 1; Fig. sis a transverse section taken on line d-d of Fig. 1; Fig. 6is a transverse section of the mercury trough, with perforated pipe and dash-plate, also an end elevation of Fig. 1; Fig. 7 is a side elevation of Fig. 2, showing electrical connections; Fig. 8 is an enlarged detail of dependent pieces, showing the action of diverging currents; Fig. 9 is a detail of metal bridge, with mercury trough for resilvering the zinc dependent pieces; Fig. 10 is a plan of my apparatus in the form of a circular tray, part shown with radiating channels and part with zigzag channels; Fig. 11 shows two methods of constructing a metal bridge in combination with a frame formed as a sieve in substitution for the dependent pieces. In the various Figures : A-A, are the sides of the chute; B, bottom ;C, zinc-lining; D, mercury wells formed in C; E, iron dependent pieces; F, bridge for B ; G, zinc dependent pieces; H, bridge for C; I, silver wells m H; J, apertures leading from I to C; X, insulating pieces for F and H; L, connections from Fto positive pole of electrical apparatus; M, connections from H to negative pole of electrical apparatus, placed preferably on the opposite side of apparatus to L ; N, mercury trough at end of chute; 0, plugs for drawing off mercury ; P, dash-plate in N; Q, perforated pipe in N; E, connections to Q ; S, receiving hopper for circular tray; T, radiating channels formed on circular tray, and provided with iron and zinc dependent pieces similar to Fig. 1; U, zigzag channels formed in circular tray, also provided with iron and zinc dependent pieces, as shown in Fig. 1; V, mercury trough; W, perforated pipe; X, framed woven wire, which may be substituted for E and G; V, spiral coils interlaced, which may also be substituted for E and G. The method of operating my apparatus is as follows:— By means of the electrical connections L the current is conveyed from the primary electrical source to F, and thence to E, which is in contact with the moving current of water and ore which is moving in the direction indicated by the arrow. Decomposition is effected by this means, and the decomposed parts are impinged against the surfaces of G, which are also influenced by the electric current transmitted from E through the medium of the liquid and the ore. Cis likewise influenced in the same manner as G, and also through G. The peculiar effect obtained by the contact of G with C is, that the particles of gold or precious metals are collected upon G, and combined with the silver in the form of amalgam, and are precipitated upon the surface of 0, more particularly at the parts where G comes in contact with C. The electrical action produces a quickening or an enlivening influence upon the amalgam, which causes some portion of it to escape from G, and, passing over the surface of C, adheres partially thereto, or is collected by the subsequent pieces G, and if not wholly retained by them, finds its resting-place in D. Should D become too fully charged so as to cause the mercury to overflow, it will simply pass into N, where it may be collected, and the amalgam separated thereform. When the water and ore has reached the end of the chute it is simply in the form of tailings which will impinge against P, by which means they are diverted into N, and their more rapid outflow is assisted by means of the water discharged from Q received from the pipe B. In order to remove the amalgam which has gathered about G, it is only necessary to break the circuit and remove the bridge, when the dependent pieces will be accessible to the attendant. The mercury wells and the plates are also accessible to the attendant in a similar way. In Fig. 10 the water and ore is fed into S, from whence it passes into T or U, and is subject to the same treatment as just described for Figs. 1 to 8. In order to silver the surfaces of G or the plates C, or to furnish a fresh supply of mercury to D, the attendant simply removes X, and by placing the silver in I, it passes down through J on to the faces of G, and thence to C and D. If it is desired to impart a vibratory motion to my apparatus for the purpose of assisting the precipitation of the precious metal, this may be done by many known mechanical appliances, and would have the effect of increasing the disturbance of the cur-