Official Changes in the Active List of Permissible Explosives and Blasting Devices for January, 1931

Economic Aspects of Gold and Silver

Official Changes in the Active List of Permissible Explosives and Blasting Devices for December, 1930

The Mineral Industry

Holmes Safety Certificate Presentation

The Mineral Industry and the Young Engineer

Official Changes in the Active List of Permissible Explosives and Blasting Devices for January, 1932

Official Changes in the Active List of Permissible Explosives and Blasting Devices for June, 1930

Official Changes in the Active List of Permissible Explosives and Blasting Devices for September, 1930

Official Changes in the Active List of Permissible Explosives and Blasting Devices for November, 1929

Official Changes in the Active List of Permissible Explosives and Blasting Devices for September, 1931

Official Changes in the Active List of Permissible Explosives and Blasting Devices for February, 1930

Official Changes in the Active List of Permissible Explosives and Blasting Devices for November, 1931

Conservation of Natural Gas in Relation to Some Recent Developments

Official Changes in the Active List of Permissible Explosives and Blasting Devices for November, 1930

Men and Mines

Official Changes in the Active List of Permissible Explosives and Blasting Devices for August, 1930

Men and Mines

Official Changes in the Active List of Permissible Explosives and Blasting Devices for October, 1931

Recent Developments in the Mining Industry