Geology and Mineral Resources of the Butler and Zelienople Quadrangles, Pennsylvania (open access)

Geology and Mineral Resources of the Butler and Zelienople Quadrangles, Pennsylvania

From abstract: This report is one of a series of publications on the geology and mineral resources of the Appalachian Plateaus. The areas described are the Butler and Zelienople quadrangles, which together include about 450 square miles in Butler, Beaver, and Lawrence Counties, western Pennsylvania.
Date: 1936
Creator: Richardson, G. B.
System: The UNT Digital Library
Microscopic Structure and Concentratability of the Important Iron Ores of the United States (open access)

Microscopic Structure and Concentratability of the Important Iron Ores of the United States

Outline of Problem: "This paper covers a survey of 19 ores collected from seven of the more important iron-ore districts of the United States and is a contribution by the ore-dressing section of the United States Bureau of Mines to general research program on iron and steel being conducted by the Bureau."
Date: 1936
Creator: Cooke, S. R. B.
System: The UNT Digital Library
Sampling and Examination of Mine Gases and Natural Gas: A Revision of Bulletin 42 (open access)

Sampling and Examination of Mine Gases and Natural Gas: A Revision of Bulletin 42

Revision of a report by the U.S. Bureau of Mines which described experiments performed in Pittsburgh, Pennsylvania to study mine gases. According to the foreword: "Much of the material is reprinted on the following pages in its original form, and changes have been made only where manifestly necessary. Laboratory methods have been brought up to date. Some types of apparatus described in Bulletin 42 have now become obsolete and newer designs are described instead" (p. 1).
Date: 1936
Creator: Burrell, George A. & Seibert, Frank M.
System: The UNT Digital Library