Use Of Stenches As A Warning In Mines PDF Download

Excerpt from Use of Stenches as a Warning in Mines Electric gongs have been tried in metal mines and also in the coal mines of Illinois, but have not been satisfactory. The sound can not. Be heard far, and the circuits are kept in repair with difficulty because of the excessive corrosion of the wires and because of accidental grounding. As a means of signaling, some mines in the West have placed three-way valves, essentially the same as the stop and waste cocks in water lines, at various points in the compressed-air line. Turning one of these valves closes the line from the compressor and releases the air from that branch of the pipe. Interruption of the flow of air is the signal for the men to leave the mine. This method, too, is not satisfactory, because accidental interruptions cause need less confusion and stopping of work. 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.