Produced by Chris Curnow, Christian Boissonnas and the Online Distributed Proofreading Team at http://www.pgdp.net (This file was produced from images generously made available by The Internet Archive) MINES AND MINING IN ALL PARTS OF THE WORLD—CAVES AND THEIR MYSTERIES—FAMOUS TUNNELS—DOWN IN THE DEPTHS OF THE SEA. VOLCANOES AND THEIR ERUPTIONS—PETROLEUM—UNDERGROUND LIFE OF MAN AND THE LOWER ANIMALS. SUBTERRANEAN WORKS OF THE ANCIENTS. BURIED TREASURES, ETC., ETC.…
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