Excerpt from Reports on the Combustible Qualities of the Semi-Anthracites of the Zerbes's Run Coal Fields, in the Shamokin Basin, of PennsylvaniaFrom about two miles east of Yellow Spring Gap of Stony Creek, westward along the Dauphin Basin to its termination within ten miles of the Susquehanna, the proportion of bitumen in the coal' increases from an average of 10 per cent. To an average of 14 or 15 per cent., ¿uc tuating in the different beds from 8 to 12 per cent. At the eastern end of this belt, and from 13 to 17 at_the western, this range includes then the dryer class of semi-bituminous coals, and towards its eastern limit some true Jami-anthra cites. And the same seams which at Yellow Spring Gap are dry semi-bituminous coals, are all of them semi-anthracites at Rausch Gap, only 4, miles further east. Into the ques tion of the sources of this difference, in the amount of volatile matter remaining in different closely contiguous coals of any group, either semi-bituminous or bituminous, I shall not here enter, as this is not a point of any obvious practical moment.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis 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.