British Army uniform and equipment in World War I It contained an inner can of explosive with an outer can of metal fragments or ball bearings. The fuses that were developed for the Jam Tin Grenade were activated by friction or a by lighted taper which was often replaced by a lighted cigarette. This was followed by the highly successful Mills bomb in 1915. It was oval in shape to fit into a clenched fist and time fused. The detonator was activated by a spring driven firing pin which was restrained by a lever that in turn was locked by a safety pin. The Mills bomb was a defensive
Iron mining in the United States produced 3.66 billion tons of ore, about 70 percent of which came from the Mesabi Range. Totals through 1965 were: The largest production of US iron ore outside the Great Lakes districts was the Birmingham, Alabama district. Sedimentary iron ore in the Red Mountain formation of Silurian age was first used to make iron in 1864. Production was small until 1881, when major steelmaking began in Birmingham. The last iron mine shut down in 1975, after the district had produced 376 million long tons of ore. Iron mining in the United States Iron mining in the United States produced 42.5