Falls of roof in mines operating in the Pittsburgh Coal Bed, West Virginia
By: by J.W. Paul and J.N. Geyer.
Contributors: Geyer, John Nicholas, 1896-
Series: U.S. Bureau of Mines. Technical paper; 547
Publisher: U.S. Govt. Print. Off.
Published: 1933
Place of publication: Washington
Language: eng
Number of pages: 23
Subjects: Coal mine accidents.; Coal mines and mining -- West Virginia.
Notes: At head of title: U.S. Department of Commerce. Roy D. Chapin, secretary. Bureau of Mines. Scott Turner, director ...