the fact that a No. 9 Sellers injector, which will throw 2000 gallons of water per hour, will not keep her supplied.

The water consumed in the 98 minutes' run to Jersey City was. about 3300 gallons, and on the return trip about 3600 gallons, or about 341 gallons, or 288 pounds per minute.

Comparing this time with the fast time made by the 7.35 A. M. going east and the 3.30 P. M. coming west, on the Pennsylvania Railroad, from Germantown Junction to Jersey City and return, we have as follows:

PENNSYLVANIA RAILROAD.-Germantown Junction to Jersey City, distance 84.2 miles, time 106 minutes, rate of speed 47.7 miles per hour.

READING RAILROAD.-Wayne Junction to Jersey City, distance 85.1 miles, time 88 minutes, rate of speed 57.6 miles per hour.

Jersey City to Germantown Junction, distance 84.2 miles, time 103. minutes, rate of speed 49 miles per hour.

Jersey City to Wayne Junction, distance 85.1 miles, time 913 minutes, rate of speed 55.7 miles per hour.

Being seventeen per cent. less time going east and twelve per cent.. coming west than that now made by the Pennsylvania Railroad.

The advantage of large diameter for driving wheels is in the reduction of the number of revolutions per mile. In the Baldwin engine

305-258 × 100 305

= 154 per cent., and their engines being coupled,

this additional number of revolutions adds to the risk by increasing the momentum of the parallel rods and tending to separate them.

It must not be supposed that 80 miles an hour is the limit of speed which a railway train may attain. Speed is a question of power and resistance, and velocities greater than 80 miles an hour, which is about 7000 feet per minute, are in use in various kinds of machinery,. to wit: fan-blowers, circular saws, etc.

The writer believes that before the expiration of five years, with the present active rivalry, passengers will be set down in New York. in one hour's time from this city.

The following table shows the speed in miles per hour of the fast lines in Europe and America.

The mean average of all the English railways is 46.2 miles per hour; French, 37.5 miles per hour; German, 40 miles per hour, and America, 37 miles per hour. The English being 20 per cent. faster than in this country.

With them, 63 feet driving wheels are quite as common as 53 feet wheels are with us; in fact some of the fast lines have 8 and 9 feet, and one line had 10 feet diameter.

Engines with one pair of drivers are not new in this country. The Ironsides, built by M. W. Baldwin in 1832, had but one pair of drivers, 4 feet in diameter. Mr. William Pettit ran her on the Phil

adelphia and Germantown Railroad at the rate of 62 miles per hour. Dr. Patterson, of the University of Virginia, and Mr. Franklin Peale were on the engine, and timed its working on that occasion.

In 1849 Edward S. Norris, of Schenectady, built for the then Utica and Schenectady Railroad the Lightning, Crampton, with 16 inch cylinders, 22 inch stroke, and a single pair of 7-feet wheels, which ran at the rate of 60 miles an hour in the year 1850, but it only worked a short time.

Messrs. M. W. Baldwin & Co., in August, 1849, delivered to the Vermont Central Railroad an engine, the Governor Paine, with 17 inch cylinders, 20 inch stroke, and a pair of 63 feet driving wheels, and subsequently sent three Crampton engines, of smaller dimensions, to the Pennsylvania Central Railroad in September, 1849.

Norris Brothers made seven engines for the Camden and Amboy Railroad, each with a single pair of 8 feet driving wheels, and a sixwheeled truck. The first of these, with 13-inch cylinders and a 34inch stroke, was sent from the makers' shops April 17th, 1849. The next of the class had 13×38-inch cylinders, and were delivered Dec., 1849. The last of the series, delivered in April, 1853, had 14-inch cylinders and a 38-inch stroke. The 13-inch cylinders weighed, empty, 40,754 pounds, and loaded, 49,253 pounds. Of the weight loaded, 18,496 pounds, or about 8 tons, were on the driving wheels, with about 13 tons on the truck, making 22 tons in all. These engines had boilers 36 inches in diameter, with plates but inch thick.

In 1850 they also built two outside cylinder engines, with 14-inch cylinders, 32-inch stroke, and coupled 7-feet driving wheels, for the New York and Erie Railroad (new Erie Railway).

In the year 1849 Ross Winans, of Baltimore, built a single locomotive for the Boston and Worcester Railroad. It was for an experiment in coal-burning and constructed to burn anthracite coal. This locomotive was named the Carroll of Carrollton. It had one pair of 7-foot driving wheels and was intended for very high speed. It had two small steam cylinders placed on the sides of the boiler, over the bearings of the driving axle, by which the weight on the drivers could be varied from three to twelve tons.

The 7-foot drivers were cast with chilled rims and were of extremely light pattern; in fact they became broken after running six weeks. These were replaced with a set of imported wrought iron wheels, the first of the kind brought to this country.

The speed of the engine, under favorable. circumstances, was one mile in sixty seconds. It was run between Albany and Boston, and the train consisted of from seven to eight cars, and made a mile a minute with ease. The engineer, J. H. Jackman, says: "Since I run her in 1849, I have traveled many thousand miles on locomotives, and have seen some high speeds made, still I have never seen the locomotive that could lay right down to it and out-run the Carroll of Carrollton. When I run her we made many stops, and therefore could not make better time than locomotives having smaller driving-wheels. But give me fifty or sixty miles on a clear run, and I could out-run a thunder storm if it was going our way. In those days we had no airbrakes, and to run at such high rates of speed sometimes became dangerous. I remember one instance, in the night-time, of rounding a WHOLE NO. VOL. CX.—(THIRD SERIES, Vol. lxxx.)

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