Note 8 — Expedition to the Mines of the Igorrotes

See Becker’s account of the gold-producing districts in Luzón, their geological conditions, and the native methods of mining (Twenty-first Annual Report of U.S. Geological Survey, part iii, pp. 576–580). He states that the Igorrotes have always refused, [279n] even to the present day, to allow any outsiders, of any race, to visit the quartz mines in their country.