1axle, one end of which is mortised into the large horizontal axle, and the
other end is held in a hollow covered with thick iron plates in a beam. Thus
the paddles, of which there are three sets in each tub, turn round, and
agitating the powder, thoroughly mix it with water and separate the minute
particles of gold from it, and these are attracted by the quicksilver and
purified. The water carries away the waste. The quicksilver is poured
into a bag made of leather or cloth woven from cotton, and when this bag is
squeezed, as I have described elsewhere, the quicksilver drips through it into
a jar placed underneath. The pure gold13 remains in the bag. Some people
substitute three broad sluices for the tubs, each of which has an angular axle
on which are set six narrow spokes, and to them are fixed the same number of
broad paddles; the water that is poured in strikes these paddles and turns
them round, and they agitate the powder which is mixed with the water and
separate the metal from it. If the powder which is being treated contains
gold particles, the first method of washing is far superior, because the quickÂ
silver in the tubs immediately attracts the gold; if it is powder in which
are the small black stones from which tin is smelted, this latter method is
not to be despised. It is very advantageous to place interlaced fir boughs
in the sluices in which such tin-stuff is washed, after it has run through the
launders from the mills, because the fine tin-stone is either held back by the
twigs, or if the current carries them along they fall away from the water
and settle down.
other end is held in a hollow covered with thick iron plates in a beam. Thus
the paddles, of which there are three sets in each tub, turn round, and
agitating the powder, thoroughly mix it with water and separate the minute
particles of gold from it, and these are attracted by the quicksilver and
purified. The water carries away the waste. The quicksilver is poured
into a bag made of leather or cloth woven from cotton, and when this bag is
squeezed, as I have described elsewhere, the quicksilver drips through it into
a jar placed underneath. The pure gold13 remains in the bag. Some people
substitute three broad sluices for the tubs, each of which has an angular axle
on which are set six narrow spokes, and to them are fixed the same number of
broad paddles; the water that is poured in strikes these paddles and turns
them round, and they agitate the powder which is mixed with the water and
separate the metal from it. If the powder which is being treated contains
gold particles, the first method of washing is far superior, because the quickÂ
silver in the tubs immediately attracts the gold; if it is powder in which
are the small black stones from which tin is smelted, this latter method is
not to be despised. It is very advantageous to place interlaced fir boughs
in the sluices in which such tin-stuff is washed, after it has run through the
launders from the mills, because the fine tin-stone is either held back by the
twigs, or if the current carries them along they fall away from the water
and settle down.