THE recent death at the age of fifty-seven years of Hugo de Böckh will occasion deep grief amongst those who in many lands enjoyed his gifts of friendship, admired his independent judgment and vigorous personality, and feel the loss to science. He was the son of a distinguished Hungarian geologist, and received part of his training under Karl von Zittel at Munich. In 1902, at the age of twenty-eight, he was appointed professor of mineralogy at the Hungarian School of Mines at Selmecz-banya, and there turned his attention to economic geology and to the tectonic problems which he realised would prove of practical value in mining. He wrote a text-book on geology in Hungarian, and amongst other investigations studied the applications of the Eötvös balance to subterranean prospecting. During the War he was appointed Under-Secretary for Mines in Hungary.