Quantitative method of estimating ground-water supplies
暂无分享,去创建一个
Introduction The water that comes from beneath the surface of the earth has from time immemorial been regarded by man as a mysterious boon—cold, clear, and presumably pure; wonderfully refreshing to the hot and weary wayfarer; essential, perhaps, to the very life of the community, yet without cost and generally regarded as inexhaustible; coming from some dark orifice in the earth, its source unknown and unknowable; a great blessing freely and mysteriously bestowed on man by some benevolent but capricious Providence. When, very rarely, in times of unusual drought, this mysterious blessing, which was regarded to be perennial and inexhaustible as the air itself, was cut off and the spring or well went dry, the occurrence was a calamity, in the face of which man stood helpless in fear and awe. When at last the geologist appeared, with his methods for beholding what is beneath the earth’s surface, concealed from . . .