2026-04-17T12:55:39Z

Mosier, McHenry., Gleim, E. J. (Ernest J.)

Title:

Some signaling systems in metal-mine shafts.

Call Number:

P19470

Date:

1939

Description:

Serial issue. Issued as: United States. Bureau of Mines. Information circular, 7083 (1939:June).

Subject Topical:

Mine safety., Signals and signaling., Mine communication systems.

All:

Signals and signaling., Mine communication systems., Mine safety.