Page:Popular Science Monthly Volume 37.djvu/246

234 veins charged with tin, intersecting the granitic masses. The washings of these veins, mingled with alluvial sands, have been carried down by the rivers and spread by them through the floods of the ages over the bottom-lands of the country. Taking advantage of this work of Nature, man, instead of quarrying in the mountain for the vein and having to blast the incasing rock, has only to look in the flats for the mineral.

The mines were worked by the Chinese, no European operator having been as yet established in the country. It did not take long to witness the extremely simple process by which the ore is



extracted. After clearing off the ground, the surface and subsoil are removed for one, two, or three metres, till the mineral, tin-bearing bed is exposed; this is sometimes several metres thick. The mineral is carried in baskets, as we have seen, up the cocoa-trunk ladders, to a wooden flume which is washed by a current of water. As the mine grows deeper this labor, with the rudimentary means at the disposition of the Chinese, is made extremely difficult by the inflow of water. The washing of the tin-bearing earth is done by coolies, who with a rake remove the stones and