THE great demand for supplies of zinc required in the manufacture of munitions, especially in the manufacture of brass shells which contain 66.6 per cent copper and 33.4 per cent zinc, led to an investigation in 1915 to ascertain the feasibility of producing metallic zinc in Canada. This resulted in the establishment of a zinc plant by the Consolidated Mining and Smelting Co. of Canada at Trail, B. C., at an initial cost of $2,500,000.