The Imperial Institute, in continuation of its publications with reference to the mineral resources of the Empire, has now issued a map with diagrams indicating the sources within the Empire of the chief metals of commercial importance. The outline map shows the occurrence in each British country of the important metallic ores and also the existence of deposits at present unworked. The locality for each occurrence is not given in detail, but only a general statement, carried out by printing the names of the metals therein found in large type across the face of the country. Asterisks indicate existence of unworked deposits in producing countries, while brackets show the existence of unworked deposits in nonproducing countries. Diagrams are also given, showing in a graphic form the production of metal or ore in each producing country; these statistics are given for the year 1915: since that date many and important changes have occurred, although no doubt it would be difficult, if not impossible, to obtain complete and reliable figures for the later years. The diagrams also show in an instructive manner the relation of the output of the British Empire to those of other countries of the world. The facts here set forth, when carefully studied, afford much food for reflection.