The dictionary of photography for the amateur and professional photographer (1897)
Wall, E. J. (Edward John), 1860-1928, Bolas, Thomas · London : Hazell, Watson & Viney · leaf 15
Acetylene direct combination of carbon and hydrogen at a high temperature as, for example, when an electric arc is produced in hydrogen. Acetylene is remarkable among hydrocarbons as containing stored in itself a large excess of energy, usually referred to as heat; hence such a substance is … two atmospheres ; that is [4 lb. on the square inch, as an to say, a pressure of about engineer would ordinarily reckon it, or counting only the addi- tional pressure beyond the normal pressure. In January, 1895, the use of acetylene as an illuminant was first discussed in the photographic papers,…
Photography
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