Show wm H child stock broker dooly block telephone 2 tf the engineering k and mining journal of march contained an abstract of a paper read before the canadian mining institute on the leaching of copper ores by sulphurous acid written by E P jennings M E of this city this is the process recently patented by J W neill of salt lake and which was fully described in an illustrated article in the mining review several month ago the new mill for the coconino mine in northern arizona will employ this process at the laboratory of B R H officer co on west temple street a small plant is used in making mill run tests by this method of copper ore reduction |