Two borehole photograph goniometers

Author:	Halstead, Perry N.
Additional Authors:	Hubbard, S. Jackson., Call, Richard D.
Year:	1968
Document Type:	BMRA
Issuing Agency:	U.S. Dept. of the Interior, Bureau of Mines,
SUDOC:	I 28.23:7097
Series:	Report of investigations / United States Department of the Interior, Bureau of Mines ;
Report Number:	7097
Subjects:	Angles (Geometry)--Measurement
	Boring
Link:	https://hdl.handle.net/2027/mdp.39015078530667