10 chaldrons of Newcastle coals, at 65s. make £ 32 10 0 8 tons of cannel coal,[15] (this coal is sold by weight) at 100s. per ton 40 0 0 7 chaldrons of common coals for carbonising, at 55s. 19 5 0 To wages paid the servant for attending the gas apparatus 30 0 0 Interest of money sunk 30 0 0 The wear and tear of the gas-light apparatus I consider to be equal to the wear and tear of lamps, candlesticks, &c. employed for oil, tallow, &c. ----------- Total expence of the gas lights 151 15 0 DEDUCT 23 chaldrons of coke, at 60s. per chaldron 69 Ammoniacal liquor 5 Tar 6 Charcoal employed by the copper-plate printers to heat their plates, which is now done with the gas- light flame, cost, annua 25 Two chaldrons of coals _minus_ used as fuel, for warming the house, since the adoption of the gas- lights, at 65s. per chaldron 6 10 ------ 111 10 0 ---------- Nett expences of the gas-lights £ 40 5 0 ---------- The lights used in my Establishment, prior to the gas- lights, amounted annually to 160 0 0 My present system of lighting with gas costs, per ann. 40 5 0 ---------- Balance in favor of the gas for one year £ 119 15 0 Such is the simple statement of my present system of lighting, the brilliancy of which, when contrasted with our former lights, bears the same comparison to them as a bright summer sun-shine does to a murky November day: nor are we, as formerly, almost suffocated with the effluvia of charcoal and fumes of candles and lamps. In addition to this, the damage sustained by the spilling of oil and tallow upon prints, drawings, books and paper, &c. amounted annually to upwards of 50l. All the workmen employed in my establishment consider their gas-lights as the greatest blessing; and I have only to add, that the light we now enjoy, were it to be produced by means of Argand’s lamps or candles, would cost at least 350l. per annum. I am, with respect, Yours, Strand, March 13, 1815. R. ACKERMAN.” [15] _Although cannel-coal sells at nearly double the price of Newcastle coal, I use it in preference to the latter, because it affords a larger portion of gas, and gives a much more brilliant light._