CHAPTER XIV

Mining--Ancient workings--Precious metals found--Copper

deposits--Iron ores--Treatment of ores in England--

Difficulties of transport--Some deceased authorities--

Mines in operation--Butters' Salvador mines--History of

undertaking--Large profits earned--Directorial policy--

Machinery and equipment--Butters' Divisadero Mines--

Butters' cyaniding plant 181-195

Salvador of the Twentieth Century · 第 14 / 27 章