Method for providing additional working faces on the lode by the constrction of intermediate horizon,, 1926

Method for providing additional working faces on the lode by the constrction of intermediate horizon,, 1926, Box: 142, Folder: 15. Saint John d'El Rey Mining Company Records, 1984-12. Benson Latin American Collection, The University of Texas at Austin. https://archives.lib.utexas.edu/repositories/4/archival_objects/345486 Accessed September 27, 2026.