Mills bomb incorporated into the Mills Bomb. The Mills bomb was adopted by the British Army as its standard hand grenade in 1915, and designated the No. 5. The Mills bomb underwent numerous modifications. The No. 23 was a variant of the No. 5 with a rodded base plug which allowed it to be fired from a rifle. This concept evolved further with the No. 36, a variant with a detachable base plate to allow use with a rifle discharger cup. The final variation of the Mills bomb, the No. 36M, was specially designed and waterproofed with shellac for use initially in
History of the iron and steel industry in the United States 2014, only 11 integrated mills were operating in the US. Most of the steel produced has been by the growing number of mini-mills, also called specialty mills, which in 2014 numbered 113. In 1981, mini-mills produced an estimated 15% of US steel. Since 2002, steel produced by electric arc furnace, the process used by the mini-mills, has produced more than half the steel made in the US. Many companies operating integrated mills also have mini-mills. A number of bankruptcies and acquisitions between 2000 and 2014 reversed the trend of industry fragmentation. In 2000, the top three steelmakers (Nucor, US Steel,