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gas gas. gas. New York $1 00 $1 08 $1 71 $14 92 $22 90 $8 70 Chicago 1 00 71 1 50 8 72 18 30 7 00 New Orleans 1 00 59 1 56 17 90 15 30 5 80 San Francisco 1 00 64 1 50 8 75 9 40 3 50 London 1 00 61 2 05 7 16 17 70 6 30 Port Natal 1 00 90 1 21 Sydney 1 00 34 1 39 Valparaiso 1 00 44 1 03 These figures are very much against the fluid fuels, but there may be circumstances in which the benefits to be derived from their use will exceed the additional cost. It is difficult to make a comparison without considering particular cases, but for intermittent heating petroleum would probably be more economical, though for a steady fire coal holds its own. * * * * * THE MANUFACTURE OF STEEL CASTINGS. At the opening meeting for the winter session of the Iron and Steel Works Managers' Institute, held at Dudley on September 12, Mr. R. Smith-Casson in the chair, Mr. B.F. McCallem, of Glasgow, read a paper on "Steel Castings," which developed an interesting discussion upon steel casting practice. Mr. McCallem said that it was thirty years since the first crucible steel castings were made in Sheffield in the general way, and with one exception the method of manufacture was pretty much the same now as at that early date. The improvement was the employment of gas furnaces instead of the old coke holes for melting. Important economies had resulted from this introduction. Where before it required 3 tons of coke to melt 1 ton of steel, the same thing was now done with 35 cwt. of very poor slack. Though it was apparently easy to make crucible steel castings, it was not in reality easy to make a true steel, that was to say, to make a metal that contained only the correct proportions of carbon and silicon and manganese. The only real way to make crucible castings of true steel was to melt the proper proportions of cast steel scrap with the proper amounts of silicon and manganese to produce that chemical composition which was known to be necessary in best castings. It was in consequence of this difficulty that many makers resorted to the addition of hematite pigs. The Bessemer process was used much more extensively upon the Continent than in this coun
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