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by the erection of suitable dams and sluices at different points of the Nile-as, for example, at the cataracts. These structures, he concludes, would also greatly improve the navigation of the river.

THE SIMPLON TUNNEL PROJECT.

This project is still the subject of newspaper discussion, though nothing of a definite nature has transpired during 1877 concerning it. We may record, however, the current report that a French company, having secured important concessions from the Italian Government, seriously contemplates the undertaking. The projected line of road would commence at Brigue, which would thus become the international entrance station to the tunnel, which, according to the statements of the projectors, would have a length of 18,340 meters. The Annales du Génie Civil affirms that the scheme is so far advanced that preliminary surveys for the tunnelwork and for the construction of the approaches are now in course of execution.

DRAINING OF THE ZUYDER-ZEE.

The engineering journals noted during the past year that active preparations were being made for the commencement of the long-projected work of draining the Zuyder-Zee. This work, which has been alluded to in former volumes of the Record, is of prodigious magnitude. It will require, according to estimate, sixteen years for its completion, and will cost about 335,000,000 francs.

MISCELLANEOUS.

During the past year, a commission of engineers appointed by the Belgian Government to decide upon the merits of the several forms of continuous train-brakes reported in favor of the Westinghouse system, after an extended series of experimental trials, and recommended its adoption upon all the Belgian state railroads. This recommendation, we understand, has since been carried into effect.

The hopes of the friends of Chinese progress have received a severe check in the action of the Chinese Government in regard to the Shanghai and Woosung Railroad, the first (and likely to be the last for some time to come) and only railway

in the Chinese Empire. For reasons best known to themselves, the authorities, after securing possession of the road by purchase, entirely suspended its operations; and, if report be correct, dismantled the road and destroyed the rolling-stock.

The Peruvian Government last year entered into an agreement with Mr. Henry Meiggs, the well-known contractor, for the construction of a drainage tunnel to make accessible the rich but long-abandoned silver - mines of Cerro de Pasco. This work, which is one of great importance, will probably be seriously affected by the death of Mr. Meiggs, which lately occurred. The St. Gothard tunnel has made satisfactory progress during 1877.

TECHNOLOGY.

By WILLIAM H. WAHL, Ph.D.,
PHILADELPHIA, Pa.

THE DUPUY DIRECT PROCESS.

This process, which was first publicly announced at the monthly meeting of the Franklin Institute in November, 1877, has been for nearly a year experimentally tested at Pittsburgh, and with such promising results as to justify one of the largest establishments of that city in erecting a plant, consisting of crusher, mill, furnaces, forge, etc., to test it commercially. The following gives in brief the novel features of the plan. Mr. Dupuy makes a suitable mixture of ground ore, flux, and coal-slack (and alkalies), and introduces the same into sheet-iron canisters of annular form, so that the heat of the furnace may penetrate the mixture from both the outer and the inner surface. The object sought to be attained by this plan is to secure the advantages of the close pot by employing a protecting envelope which will withstand the high heat required for the reduction, and which, when the operation is completed, may be welded up with the metal.

The inventor describes three methods of working the process, according to the purpose for which the metal is designed:

1. For steel-making, the canisters are charged on end into the furnace, on a layer of coke a few inches in thickness. When reduced (in from five to seven hours), it forms a very firm metallic mass, which is removed and hammered, or thrown into a squeezer and rolled into muck-bar. The latter is reheated, cut up, piled, and put into the steel-pot.

2. The reduced metal may be remelted in a Siemens open hearth, with or without the usual carbonizing bath of pig and spiegel.

3. The metal, when reduced, may be melted down in the same furnace and carbonized with pig-iron. The following

details may be instructive: "Canisters of No. 26 sheet-iron, fifteen inches outside diameter and thirteen inches high, with a tube six inches diameter passing through and through in the centre, including top and bottom, will weigh six pounds. They will hold one hundred and sixteen pounds each of 67 per cent. ore, besides the carbon and fluxes. Each canister will yield from 75 to 80 per cent. of the metallic iron, including the six pounds of sheet-iron canister. An estimate for metal transferred in the canisters, while hot, to the openhearth furnace, sufficient for one ton of steel stock, exclusive of wear and tear and general expenses, foots up to $17.23."

ANOTHER DIRECT PROCESS,

The invention of Dr. Siemens, has also been spoken of during the year. The inventor is still engaged in experimenting, with the view of further improvements, and hence no results are available. So far as we can learn, the process consists in melting cast-iron and iron ore together in a furnace, by which the carbon of the former combines with the oxygen of the latter, and leaves the resulting mass free from carbon. From time to time samples of the metal are drawn from the furnace and the progress of the transformation observed. When all the carbon has disappeared, a requisite quantity of spiegel-eisen is added, and the mass thereby converted, as in the Bessemer process, into steel.

COMPARISON OF A COAL-FURNACE AND A SIEMENS GASFURNACE IN THE MANUFACTURE OF PLATE-GLASS.

The following comparative statement, furnished by one of our leading Western establishments, affords a striking evidence of the superiority of the gas-furnace in this special industry:

The coal-furnace contained twelve pots, each having a capacity of 800 pounds-giving, therefore, 9600 pounds to a melt, averaging twelve hours to a heat, and consuming twelve tons of coal per twenty-four hours. The flame intensity was unequal, and in consequence of this non-uniformity of heating, the breakage of pots was considerable. The quality of glass made was variable; and from the impure character of the flame, the pots needed considerable skim

The Siemens gas-furnace that replaced the above contained sixteen pots, each having a capacity of 1000 poundsgiving, therefore, 16,000 pounds to a melt, averaging twelve hours to a heat, and consuming four and a half tons of coal per twenty-four hours. The quality of product was uniformly excellent. If required, eight melts per week can be made. The uniformity of the heating and the purity of the flame effected a notable saving of pots (as much as 50 per cent. over the old furnace). But trifling skimming was required, and the yield of product per melt is fully 30 per cent. greater than in the coal-furnace.

The gas-furnace supplying the above facts was started in August, 1877, and at the time of writing shows but little wear; and during September but four pots out of the sixteen were broken.

TELEGRAPHY.

The report of the President of the Western Union Telegraph Company for the year ending June 30, 1877, showed that the company operated 76,955 miles of line and 194,323 miles of wire-being an increase of 3423 miles of line and 10,491 miles of wire as compared with the preceding year. These data do not, of course, include the lines operated by rival companies, and by numerous railroads and other corporations and business firms throughout the country, and which would very largely swell the figures named above. The arrangement made last year between the Western Union Company and the Atlantic and Pacific Telegraph Company, by which the gross receipts of the combined companies shall be pooled and divided upon a certain basis. agreed upon, was one of the notable commercial events of the past year, the substantial business effects of which consolidation will be likely to accrue to the companies more palpably than to the public. The quadruplex system has been largely introduced in this country during the year, and is rapidly growing in favor in England.

The agitation of the question of underground lines in cities, which was more earnest than ever before, does not appear to have borne any substantial fruit during the past. year in this country. Abroad, however, the German Government has been steadily perfecting and completing an extensive network of subterranean lines to connect the chief

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