ONE of the most successful of the manufactures which have been established in this country by reason of the war is that of metallic tungsten. This metal occurs naturally in the form of oxide, together with the oxides of iron, manganese, and calcium. Pure tungsten powder is obtained by first isolating the tungstic oxide and then reducing it, whilst ferro-tungsten is obtained by reducing the mixed oxides. For the production of the best high-speed steel metallic tungsten powder is necessary, because ferro-tungsten contains impurities which are eliminated only when the process of separating the tungstic oxide from the ore is employed. Before the war almost all the pure tungsten powder was supplied by Germany, whilst ferro-tungsten was manufactured in France and, on a small scale, in this country. On the declaration of war only a limited stock of tungsten existed in this,country, whilst the necessity for a large output of high-speed steel was urgent. The way in which it was supplied is described in an article in the Chemical Trade journal for December 9.