Gold Milling Process -Primitive and Basic
A fair day's work of one Chinaman in the river-bed (say six hours' actual work) was found, as the average of several trials, to produce an output of 7.3 grains of gold about .940 fine, worth say little in local currency. This quantity of gold was obtained by washing 22 large dulangs of gravel, each holding about 70 pounds of dirt.
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