Wilkinson on its precipitation on iron pyrites, [51], [52]

Gold (Alluvial) Origin of, [17], [49], [50], [51];

Prospecting for, [17]

Gold extraction, [11], [12], [59] et seq.;

necessity of scientific procedure, [60];

German organisation, [60];

early methods, [61];

modern methods, [61] et seq.;

hydraulicing, [62], [65];

mills and crushers, [66-72];