This is most important, deposits in locations where there is not and in nearly every instance governs sufficient fall to permit the ground sluic- the chances of success in using dredges ing or hydraulic methods, in countries for placer mining. Should the bed-rock where debris laws are operative,… … A RISDON DREDGE STACKING UP TAILINGS FROM THE GOLD-SAVING TABLES it will be impossible to recover the best, der pressure, it will be necessary to re- or bed-rock values, contained in the sort to either the hydraulic elevator or gravels. There are some large tracts dredging process. of alluvial…
Engineering
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