I: Tungsten Hexabromide, II, Tungsten Complexes, a Thesis Presented to the Faculty of the Graduate School of the University of Pennsylvania in Partial Fulfillment, of the Requirements for the Degree of Doctor of Philosophy #231655

The best results were obtained with a finely divided tung sten, formed by heating tungsten trioxide in hydrogen for a long time, at as low a temperature as possible, care being taken that the metal was entirely reduced. The tungsten formed in this way is black in color and is more finely divided than the grey variety. The metal was not permitted to remain in contact with the air because it absorbs both oxygen and moisture. It was preserved in dry hydrogen.