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1887 Proc. Royal Soc. 43 119 (heading) Experiments upon the luminous phenomena of the various metals volatilised in the bunsen burner and the oxy-coal-gas blowpipe flame.

1936 E. A. Atkins & A. G. Walker Electr. Arc & Oxy-acetylene Welding (ed. 3) i. 7 The use of the oxy-coal gas welding is confined to low temperature work such as lead burning, brazing, etc.

1989 A. C. Davies Sci. & Pract. Welding (ed. 9) I. i. 46 The oxy-coal-gas flame is very similar [to the oxy-hydrogen flame], as the coal gas consists of hydrogen, together with other impurities.