Louis Denayrouze's Aerophore for Mines

An apparatus, invented by M. Denayrouze called an aerophore, has lately attracted much attention in England, and the tests made have proved it to be of practical value for just such service. By its aid, says the inventor, a man, encumbered by no more than 8 or 10 lbs. weight of apparatus, may penetrate at once and to a great distance into a pit filled with choke damp or any other gas, remain there for several hours, carry a lamp with him without danger, and have free use of his arms. The apparatus is of two kinds; a low pressure apparatus, which requires that air should be pumped to the miner through india rubber tubing from the nearest point at which pure air can be found; and the high pressure apparatus, which enables the miner to carry his own supply of fresh air in a receiver, and thus make him independent of communication from without. So satisfactory were the experiments considered, that the apparatus was regarded as invaluable for enabling a miner to explore a working charged with gas or to recover a man who could not otherwise escape, and orders were at once given for several to be kept at the collieries in the neighbourhood of the place where the experiments were made.

Text excerpt from: Nova Scotia Department of Mines Annual Report: 1873 (source)
Image from London Illustrated News (source)