A—HEAD OF THE SLUICE. B—RIFFLES. C—WOODEN SCRUBBER.
D—POINTED STICK.
E—DISH. F—ITS CUP-LIKE DEPRESSION. G—GROOVED DISH.
E—DISH. F—ITS CUP-LIKE DEPRESSION. G—GROOVED DISH.
The cup-like pockets and grooves are cut or burned at the same time into
the bottom of the sluice; the bottom is composed of three planks ten feet
long, and is about four feet wide; but the lower end, through which the water
is discharged, is narrower. This sluice, which likewise has side-boards fixed
to its edges, is full of rounded pockets and of grooves which lead to them,
there being two grooves to one pocket, in order that the water mixed with
sand may flow into each pocket through the upper groove, and that after the
sand has partly settled, the water may again flow out through the lower
groove. The sluice is set in the river or stream or on the bank, and placed
on two stools, of which the first is higher than the second in order that the
gravel and small stones may roll down the sluice. The washer throws sand
into the head with a shovel, and opening the launder, lets in the water, which
carries the particles of metal with a little sand down into the pockets, while
the gravel and small stones with the rest of the sand falls into a tub placed
below the sluice. As soon as the pockets are filled, he brushes out the
concentrates and washes them in a bowl. He washes again and again
through this sluice.
the bottom of the sluice; the bottom is composed of three planks ten feet
long, and is about four feet wide; but the lower end, through which the water
is discharged, is narrower. This sluice, which likewise has side-boards fixed
to its edges, is full of rounded pockets and of grooves which lead to them,
there being two grooves to one pocket, in order that the water mixed with
sand may flow into each pocket through the upper groove, and that after the
sand has partly settled, the water may again flow out through the lower
groove. The sluice is set in the river or stream or on the bank, and placed
on two stools, of which the first is higher than the second in order that the
gravel and small stones may roll down the sluice. The washer throws sand
into the head with a shovel, and opening the launder, lets in the water, which
carries the particles of metal with a little sand down into the pockets, while
the gravel and small stones with the rest of the sand falls into a tub placed
below the sluice. As soon as the pockets are filled, he brushes out the
concentrates and washes them in a bowl. He washes again and again
through this sluice.