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 tinstone, 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washing in the other strake, and then the plug is withdrawn and the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
