Agricola, Georgius, De re metallica, 1912/1950

Table of figures

< >
[Figure 181]
[Figure 182]
[Figure 183]
[Figure 184]
[Figure 185]
[Figure 186]
[Figure 187]
[Figure 188]
[Figure 189]
[Figure 190]
[Figure 191]
[Figure 192]
[Figure 193]
[Figure 194]
[Figure 195]
[Figure 196]
[Figure 197]
[Figure 198]
[Figure 199]
[Figure 200]
[Figure 201]
[Figure 202]
[Figure 203]
[Figure 204]
[Figure 205]
[Figure 206]
[Figure 207]
[Figure 208]
[Figure 209]
[Figure 210]
< >
page |< < of 679 > >|
1 196[Figure 196]
A—LAUNDER. B—INTERLACING FIR TWIGS. C—LOGS; THREE ON ONE SIDE, FOR THE
FOURTH CANNOT BE SEEN BECAUSE THE DITCH IS SO FULL WITH MATERIAL NOW BEING
WASHED. D—LOGS AT THE HEAD OF THE DITCH. E—BARROW. F—SEVEN-PRONGED
FORK. G—HOE
The third method of washing materials of this kind follows. Two
strakes are made, each of which is twelve feet long and a foot and a
half wide and deep.
A tank is set at their head, into which the water flows
through a little launder.
A boy throws the ore into one strake; if it is of
poor quality he puts in a large amount of it, if it is rich he puts in less.
The
water is let in by removing the plug, the ore is stirred with a wooden shovel,
and in this way the tin-stone, mixed with the heavier material, settles
in the bottom of the strake, and the water carries the light material into the
launder, through which it flows on to a canvas strake.
The very fine tin­
stone, carried by the water, settles on to the canvas and is cleansed.
A low
cross-board is placed in the strake near the head, in order that the largest
sized tin-stone may settle there.
As soon as the strake is filled with the
material which has been washed, he closes the mouth of the tank and continues
washing in the other strake, and then the plug is withdrawn and the
water and tin-stone flow down into a tank below.
Then he pounds the sides

Text layer

  • Dictionary
  • Places

Text normalization

  • Original
  • Regularized
  • Normalized

Search


  • Exact
  • All forms
  • Fulltext index
  • Morphological index