Report issued by the Bureau of Mines over the progress made on flood prevention in anthracite mines. As stated in the report, "the broad objective of the investigative work was to obtain factual data on: 1. anthracite reserves of Pennsylvania, 2. underground water pools, 3. barrier pillars, 4. the "buried valley" of the Susquehanna River, and 5. infiltration of surface water into underground mine workings" (p. 4). This report includes tables, graphs, maps, photographs, and illustrations.