C.—2

time has elapsed for the cyanide to do its work the contents of the agitator are pumped to the No. 2 Dorr thickener—similar to the No. 1 Dorr thickener—and the thickened pulp is then passed through an Oliver filter, whore the gold solution is oxtraoted and sent to the Merrill-Crowe plant, where the gold is precipitated by means of zinc-dust. The zinc-gold precipitate obtained in the Merrill-Crowe plant is caught in a bag-filter, and to obtain tho gold the bags, with contents, are dried off in a furnace and then fluxed and melted in a

tilting oil-furnace. With regard to the roaster, it is interesting to note that tho flue-gases aro led through a dust-collector, thence to a circular steel condensing-tower before passing out through the stack, and the dust collected in the dust-collector is returned to the No. 1 Dorr thickener for further treatment. Work is now being done to convey the fumes from the roaster stack to a point far removed from the mill-site, in order to eliminate all trace of arsenic and sulphur from the vioinity of the works.

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