Excerpt from Approved Electric Lamps for Miners When small electric bulbs, with their clear, white light, and small electric storage batteries became available, the advantage of com bining these elements for a miner's lamp seemed manifest. The com bination looked simple and safe, but was soon found to have ele ments of danger and weakness peculiar to itself. The Bureau of Mines showed, in 1911, that the breaking of a miniature electric bulb in an inflammable mixture of gas and air might ignite the mixture, so that only the fragile glass of the lamp bulb might stand between the miner and injury or death. There was also a possibility that sparks from the small battery would ignite gas, and the accidental spilling of the contents of a battery on the miner's clothing or skin was a possible source of injury. 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.