Excerpt from Coal Washing There will be always a difference between ideal performance and what is actually accomplished. A coal washery is an ex pensive installation, built for long service. During its useful life the art of coal washing may advance uninterruptedly. The necessary and justifiable desire of the operator to try out all useful inventions, tends in some degree to equalize the above difference. New apparatus can be added to an Old washery, but the total reconstruction of an existing plant, so as to bring it' up to modern practice, is hardly justified, since on account of the constant changes in our ideas and the development of new machinery, the remodeling of a plant would never be finished. To neglect in this description the older types of washeries, which are still in operation and doing good work, would put the present and future into too prominent a place. This book is intended to furnish the coal operator with the necessary knowledge whereby he may distinguish in washeries between the modern and earlier apparatus and methods which may be working side by side. Everything is omitted concerning apparatus which because of a lack of progressive spirit is still in use, even though it be archaic. Only a study of the chronological development of the art of coal washing will enable us to make a judicious selection of equipment. An effort is here made to set up a proper or standard rule for guidance in the presentas well as the future, from a survey of the experience of the past, with its mistakes and blind alleys, its roundabout ways and unwarranted short-cuts. Only such methods will be omitted as have been proven impracticable and useless. 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.