Our Quarters in Libby Prison, 1008 125. Tail Piece, 1016 UNDERGROUND. I. BELOW THE SURFACE. DIFFUSION OF KNOWLEDGE.—WHAT THE WORLD BELIEVES.—MUNGO PARK IN AFRICA.—WHY THE NATIVES PITIED HIM.—EXTENT OF UNDERGROUND LIFE.—DISTRIBUTION OF THE EARTH’S WEALTH.—VALUE OF MINES.—THEIR EXTENT AND IMPORTANCE.—COAL AND IRON.—MYSTERIES OF MINES.—EXPERIENCE WITH A NOVICE.—CHANGES OF SEASONS TO A MINER.—DANGERS IN MINES.—LIFE IN CAVERNS.—UNDERGROUND IN METAPHOR.—SOCIAL MINING.—OBJECT OF THIS VOLUME. In these days of fast presses, cheap books and newspapers, lightning telegraphs, and other disseminators of intelligence, there may be those who doubt the correctness of the adage which says, “One half the world does not know how the other half lives.” Human nature is inquisitive. We are constantly seeking information regarding the affairs of others, and we generally manage in some way to obtain what we seek. We store our minds with useful and useless knowledge of the manners and customs of people in other lands, and of the private lives and histories of our near neighbors. Very often the material we thus lay aside in our mental store-houses does not particularly concern us, but, like Mrs. Toodles, in her purchase of a door-plate bearing the name of Thompson with a p, we think it will be handy to have at some future day, and so we keep it. With a fair devotion to inquiries, and a well-cultivated memory, a life of threescore and ten years ought, at this day, to acquaint its possessor with a general knowledge of the how and why of the existence of at least half the inhabitants of the globe. [Sidenote: VARIED TASTES]