Gold mining Rocker box (cradle) The Gold Seekers
Collier''s New Encyclopedia from 1921 defines this device as a mechanical contrivance used in placer mining, consisting of a box on rockers and moved by hand, used for washing out the goldbearing soil. Rocker allowed to separate gold and other heavy elements from sand and gravel by shaking and rocking the highsided box, open on one end and top. The whole box was placed on rockers and