A Practical Manual On Sea Water Distillation
With A Description Of The Necessary Machinery For The Process

FUELS. 63 Per cent. Hydrogen,.......................54 Hydrocarbons (marsh gas, &c.)> . . 35 Carbon monoxide,.................6 Sundries, mostly nitrogen, ... 5 100 When coal gas is mixed with air, in the proportion of 1 of gas to from 4 to 14 of air, the mixture will explode on being ignited. The most highly explosive proportion is 1 of gas to 8 of air. Gas Pressure. 17. The average pressure of town gas, as supplied by the gas companies to houses, is from 1 to 3 inches head of water, or about 0'037 to O’ 111 lb. per square inch. There- fore, when describing the amount of gas consumed by a particular gas stove, it is usually intended that the pressure at mid-day is meant, unless otherwise stated. 18. The following short Table gives approximately the proportionate amount of gas passed at different pressures. TABLE J.—Gas Pressures. If a pressure of 1" head of water passes 1 cub. ft. of gas through a given burner in a given time— Then, ,, IK 1'2 „ through the same. 99 2" 1'4 99 99 2F 1'6 99 99 3" 1’8 19. As the mode of measuring gas (by the 1,000 cubic feet) is not always fully understood, the following ex- planation is here given. For measuring purposes, every cubic foot of gas is taken to be at the pressure of the atmosphere, so that when gas is passing through the