The Optical Magic Lantern Journal (June 1896)

The Optical Magic Lantern Journal and Photographic Enlarger. boiler which is expensive both in first cost and maintenance, and liquid acetylene requires large storage vessels, whereas simple apparatus only is needed with the carbide. The calorific value of acetylene is, according | to Julius Thomsen, 11,923; the molecular weight 64:40 parts Ca, 24 parts C.; specific gravity when compared with air, 0-91; density at 82 deg., and 30 inches bar. pr. 0-078 lb. per cubic foot ; water at 60 deg. F. at atmospheric | pressure dissolves about one volume of acetylene. In Aierica carbide of calcium is manufactured at Spray, N.C., by the Willson | Aluminium Compauy ; at Niagara Falls, by the | Carbide Company; and at the works of the Electric Smelting and Aluminium Company, Lockport, N.Y.; and in Europe, by the Hlectro-Chemische Works at Betterfield, Prussia; | at Neuhausen, by the Aluminium Industrie Actien Gesellschaft ; in Germany, at the Mann| heim Works at Baden; in France by the : Hlektro-Metallurgical Works at Froges and | Vallorbes. The exact cost of the spray plant chargeable to the production of carbide is almost impossible to determine accurately, since much of the plant has been installed for purely experimental purposes. are based on actual costs :— The following estimates, however, | Land ... ... & 100 Building 1,250 Turbine = was 2,892 Electric plant ... 6,000 Counter shafting 200 Crusher and mil] 1,025 Rolls ... 238 Furnaces ... ... ... 150 Equipment, tools, ete. 100 $11,955 Labour : Superintendent at $4 | perday ... ... 1. 2... $4:00 Labour : Three squads of men, eight hours each 7:00 11:00 Output of gross carbide in one ; day of 24 hours ... 2,000 lb. Materials, carbon for upper electrodes at 6 cents per lb.... $086 | Coke from ‘Pocohontas Mines, Va., $1:50 per ton f.o.b. Cost delivered, $4°55 per ton. Daily consumption, 2,000 lb, x 1-125 = 2,250 Ib. 5*119 95 Lime from Carson Lime Company, of Riverton, Va., about $1-75 per ton f.o.b., average cost delivered 6°30 per ton 8-411 $14-390 Materials per day and per ton of gross carbide... ... ... $14:39 Labour, per day and per ton of gross carbide oe 11-00 Water-power, 1,299 5-365 3°37 Petty stores, waste, etc., $150 perannum... ... ... .. 0-41 Taxes, at $100 per annum 0:274 Interest on investment at 5 per cent:, $11:955 ... : 1-638 Depreciation and repairs, 5 per cent. on electric plant and turbine Se. Bee oe. Ses 1:218 6 per cent. on countershafting, building, rolls and crusher 446 20 per cent. on furnaces ... 021 $32-767 The estimate, therefore, of the cost of pro | ducing calcium carbide at Spray, by working : the furnaces 365 days a year, and 24 hours a ' day, yielding on an average 1 ton of 2,000-Ib. gross carbide a day is 32,767 per ton. Of this amount, $14°39 is for material. The freight charges on lime and coke are heavy at Spray, | and add materially to the cost. The net carbide in the tests gave an average | yield of 4-926 cubic feet of moist acetylene gas ' per pound, making an average yield of 4°696 cubic feet of moist acetylene per pound of gross carbide. Pure calcium carbide should yield | theoretically approximately 6 cubic feet of gas per pound, when saturated with aqueous vapour at 60 deg. F., so that the net carbide averaged only 82:1 per cent., and the gross carbide only 78:26 per cent. of the theoretical yield. The acetylene yielded, however, was practically pure. ‘0: Acetylene Gas in Italy. By W. Mizes Barnes (Florence). J HAvE been rambling over the continent for soiné months past, and the last number of the Macic Lantern JourNAL which reached me is dated January, consequently I do not know what progress has been made in England