An automatic electric man-hoist for slopes or inclines

Author:	Ash, S. H.
Year:	1930
Document Type:	MAIN
Issuing Agency:	U.S. Dept. of Commerce, Bureau of Mines,
SUDOC:	C 22.11:6301
Series:	Information circular ;
Report Number:	6301
Subject:	Mining machinery
Link:	https://hdl.handle.net/2027/mdp.39015095083823