268 CURRENT TOPICS. [J. F. I.

New Fuel. ANON. (Amer. Mach., xxxix, No. 2o, 834.)--A new fuel for automobiles and internal-combustion engines is an- nounced, in British papers, under the name of Economin. This has for its base 80 per cent. of kerosene, the remainder being chemicals which form an emulsion. Then the mixture is distilled and gives a fuel which is cheaper than gasoline, in England at least, and which gives more power from the same motor. It is further claimed to give practically perfect combustion, so that there is almost no carbon deposit in the cylinders, to be almost odorless, and to make an easy- starting motor. It can be used with the same carburettor adjust- ment as gasoline. The fuel is not yet on the market, but a plant to turn out 2o,ooo,ooo gallons per year is under construction.

The Baldwin Locomotive Works. .ANON. (Amer. Mach., xxxix, No. 16, 652.)--This locomotive works, after 82 pears of con- tinuous operation, has produced 40,00o locomotives: The first was completed in 1832; when the industry was in its infancy. The five thousandth locomotive was built in 185o, eighteen years later, during which period two important types of freight locomotives, the " Mogul " and " Consolidation," were introduced and widely adopted. From 1889 to 19o2 , when locomotive number 20,0oo was built, com- pound locomotives came into extensive use; and trailing, wheels, allowing increased boiler capacity without imposing excessive loads on the driving wheels, were introduced. The average annual produc- tion for the five years from 19o2 to 19o 7 was approximately 2000 locomotives, and locomotive No. 30,000 was built in 19o 7 . During this period occurred the introduction of the Mallet articulated com- pound locomotive and the adoption of the Walschaerts valve motion. This period has been marked by the extensive use of superheaters, brick-arches, and other devices ; and the mechanical stoker is another accessory developed during the past few years.

Nitrogen in Iron. W. HERWlG. (StaM und Eisen, xxxiii, i72I. ) - -The gas contained in the blisters formed on steel plates during rolling and annealing was found to consist chiefly of nitrogen. The gases evolved during the solidification of iron immediately after tap- ping from the blast furnace include large quantities of hydrogen and carbon monoxide, white iron containing more hydrogen, and hot-blast gray iron more carbon monoxide. The nitrogen in steel turnings was reduced by heating in a current of hydrogen from 0.o22 to 0.0o6 per cent., and, although it was not increased by heating in a current of nitrogen, yet from a mixture of nitrogen and hydro- gen in equal proportions a steel was obtained, in one case, with as much as o.o52' per cent. nitrogen. The author considered that a similar action takes place in the converter. A steel containing 0.04 per cent. nitrogen, when tested, broke without elongation, but was improved by prolonged annealing.