Excerpt from Contributions to Economic Geology, Vol. 2: Short Papers and Preliminary Reports, 1915; Mineral Fuels This volume is the ninth of a series that includes Bulletins 316, 341, 381, 431, 471, 531, 541, 581, and 621, Contributions to economic geol ogy (part II) for 1906, 1907, 1908, 1909, 1912, 1913, and 1915, respectively. Previous to 1906 the annual Contributions consisted of one part only and papers on mineral fuels were included with the papers on metals and nonmetals except fuels in a single vol ume. These earlier volumes are Bulletins 213, 225, 260, and 285, for 1902, 1903, 1904, and 1905, respectively. Beginning with the present volume the year included in the title will be the year of publication' instead of the year in which the field work reported was done. This volume is therefore dated 1915, and there will be no volume entitled Contributions to economic geology. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.