Archive image from page 365 of De re metallica (1950). De re metallica deremetallica50agri Year: 1950 328 BOOK VIII A—Cross grooves. B—Tub set under the sluice. C—Another tub. IS to be washed, is thrown into the head and stirred with a wooden scrubber; in this way the water carries the Hght particles of gold on to the canvas, and the heavy ones sink in the pockets, and when these hollows are full, the head is removed and turned over a tub, and the concentrates are collected and washed in a bowl. Some people make use of a sluice which has square pockets with short vertical recesses which ho
Archive image from page 365 of De re metallica (1950). De re metallica deremetallica50agri Year: 1950 328 BOOK VIII A—Cross grooves. B—Tub set under the sluice. C—Another tub. IS to be washed, is thrown into the head and stirred with a wooden scrubber; in this way the water carries the Hght particles of gold on to the canvas, and the heavy ones sink in the pockets, and when these hollows are full, the head is removed and turned over a tub, and the concentrates are collected and washed in a bowl. Some people make use of a sluice which has square pockets with short vertical recesses which hold the particles of gold. Other workers use a sluice made of planks, which are rough by reason of the very small shavings which stiU chng to them ; these sluices are used instead of those with coverings, of which this sluice is bare, and when the sand is washed, the particles of gold cling no less to these shavings than to canvas, or skins, or cloths, or turf. The washer sweeps the sluice upward with a broom, and when he has washed as much of the sand as he wishes, he lets a more abundant supply of water into the sluice again to wash out the concentrates, which he collects in a tub set below the sluice, and then washes again in a bowl. Just as Thuringians cover the sluice with canvas, so some people cover it with the skins of oxen or horses. They push the auriferous sand upward with a wooden scrubber, and by this system the light material flows away with the water, while the particles of gold settle among the hairs ; the skins are afterward washed in a tub ; and the concentrates are colleced in a bowl.
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Keywords: 1900, 1950, agricola_georg_1494_1555, archive, book, bookauthor, bookcentury, bookdecade, bookpublisher, booksubject, bookyear, drawing, historical, history, hoover_herbert_1874_1964, illustration, image, metallurgy, mineral_industries, new_york_dover_publications, page, picture, print, reference, vintage
