A Practical Treatise on Gas-light / Exhibiting a Summary Description of the Apparatus and Machinery Best Calculated for Illuminating Streets, Houses, and Manufactories, with Carburetted Hydrogen, or Coal-Gas, with Remarks on the Utility, Safety, and General Nature of this new Branch of Civil Economy.

by Friedrich Christian Accum

In the year 1808, Mr. Murdoch presented to the Royal Society his account of the application of gas-light, and was complimented with Count Romford’s medal for the same.

The following statement is taken from Mr. Murdoch’s paper.

“The whole of the rooms of the cotton mill of Mr. Lee, at Manchester, which is I believe the most extensive in the United Kingdom, as well as its counting-houses and store-rooms, and the adjacent dwelling house of Mr. Lee, are lighted with the gas from coal. The total quantity of light used during the hours of burning has been ascertained, by a comparison of shadows, (see [page 23]) to be about equal to the light which 2500 mould candles, of six to the pound, would give; each of the candles with which the comparison was made consuming at the rate of 4-10ths of an ounce (175 grains) of tallow per hour.

“The gas-burners are of two kinds: the one is upon the principle of the Argand lamp, and resembles it in appearance; the other is a small curved tube with a conical end, having three circular apertures or perforations, of about a thirtieth of an inch in diameter, one at the point of the cone, and two lateral ones, through which the gas issues, forming three divergent jets of flame, somewhat like a fleur-de-lis. The shape and general appearance of this tube has procured it, among the workmen, the name of the cockspur burner.

“The number of burners employed in all the buildings amounts to 271 Argand, and 653 cockspurs, each of the former giving a light equal to that of four candles of the description above-mentioned; and each of the latter a light equal to two and a quarter of the same candles; making therefore the total of the gas-light a little more than equal to that of 2500 candles, six to the pound. When thus regulated, the whole of the above burners require an hourly supply of 1250 cubic feet of the gas produced from cannel-coal; the superior quality and quantity of the gas produced from that material having given it a decided preference in this situation over every other coal, notwithstanding its higher price.

“The time during which the gas-light is used may, upon an average of the whole year, be stated at least at two hours per day of 24 hours. In some mills, where there is over work, it will be three hours; and in the few where night work is still continued nearly 12 hours. But taking two hours per day as the common average throughout the year, the consumption in Messrs. Philips and Lee’s mill will be 1250 × 2 = 2500 cubic feet of gas per day; to produce which 700 weight of cannel-coal is required in the retort. The price of the best Wiggan cannel-coal (the sort used) is 13¹⁄₂d. per cwt. (22s. 6d. per ton) delivered at the mill, or say about eight shillings for the seven hundred weight. Multiplying by the number of working days in the year (313,) the annual consumption of coal will be 110 tons, and its cost 125l.

“About one-third of the above quantity, or say forty tons of good common coal, value ten shillings per ton, is required for fuel to heat the retorts, the annual amount of which is 20l.

“The 110 tons of cannel-coal, when distilled, produce about 70 tons of good coke, which is sold upon the spot at 1s. 4d. per cwt. and will therefore amount annually to the sum of 93l.