curve at about sixty miles per hour, when a danger signal met my view. I shut off steam and whistled down brakes, but they did not seem to check me. I whistled again; still the speed kept up. I gave the third signal for brakes, and then reversed my engine, saying to her 'Do your duty, my beauty, or in twenty seconds it is good-bye to railroading.' We came to a stand-still eighty rods from a train on the main track, having run one mile and a quarter from the place where I first discovered the red light. A locomotive engineer, to avoid trouble, must take time by the forelock-in other words, must anticipate possibilities."

Not over a dozen and a half of single engines have been made in the United States. Smaller wheels have been substituted for nearly all of these engines, from the fact that all the large-wheeled engines had small boilers, and with a single pair of driving wheels the adhesion was in all cases insufficient for the want of a proper distribution of the weight excess, as in the case of the Carroll of Carrollton, and, as before stated, the adhesion weight could be varied between three and twelve tons.

The present Baldwin has a similar arrangement, as before described, also the great advantage of a large boiler with ample heating and grate surface.

The Great Western Railway of England has seven feet gauge and was the fastest road in the world until a few years since, and its express ran regularly from Paddington (London) to Bristol, 118 miles, in precisely two hours, being at the rate of fifty-nine miles per hour.

The engines have 18-inch cylinders, 24-inch stroke, 8-feet driving wheels, and those of the largest size have 21 square feet of fire grate and a total heating surface of 1952 square feet. It has been said of them that they would evaporate from 300 to 360 cubic feet of water per hour, and are known to have worked up to quite 1000 indicated horse-power. At 60 miles an hour, 1000 horse-power would correspond to a mean effective pressure of 77.16 pounds per square inch upon the pistons (1851).

The difficulties so far for very large wheeled engines upon the narrow gauge are these: If the boiler is over the axle, the engine is topheavy; if the boiler is beneath the axle of any pair of driving-wheels less than 12 feet in diameter, the form of the fire-box and disposal of the tubes are unsatisfactory, while, if the driving axle is behind the

fire-box (as in Norris Brothers' engines for the Camden and Amboy Railroad) hardly enough weight can be secured for adhesion. A large wheel, moreover, implies a large boiler, and not only is it difficult to provide room in a narrow-gauge engine for a very large boiler, but, beyond a certain size, there is a chance of failure under high pressures. The following illustration represents the best average type of single express locomotives in general use on English railways for the last twenty years for the fast trains:

The above represents the "Lady of the Lake," the favorite pattern on the London and Northwestern Railway. This engine was exhibited at the International Exhibition in London, in 1862, and obtained a bronze metal for excellence of workmanship.

This engine was designed and constructed by Mr. John Ramsbottom. The following are its principal dimensions:

Length of wheel-base in feet,

Total weight of engine in working order in ton,

15.5

27.

Weight on leading wheels of engine in pounds, 20,056.

The tractive force for each pound effective steam pressure per square. inch on the piston this engine is capable of exerting will be

The engine Watt, one of the same class and build, run the special train which conveyed the Queen's messenger bearing the dispatches containing the decision of the American Government in the case of the "Trent" difficulty, in 1862, from Hollyhead to Stafford, a distance of 131 miles, without a single stoppage. The journey was made in 144 minutes, being at the rate of fifty-four and a half miles per hour. This remarkable run was made without stopping by the aid of Mr. Ramsbottom's "pick-up" apparatus for supplying the tender with water while running. This arrangement has been adopted by the Pennsylvania Railway, and by the use of which they have been able to reduce the size and weight of their tenders for running long distances.

The chief features of the above locomotives are that they steam well and run well, their average consumption being 22 pounds of Welsh coal per mile.

Tender "picking up" water from feed-trough when in motion.

The tender of the engine has six wheels, and weighs empty about 91 tons; full, 171⁄2 tons, and the load is equally distributed on the wheels.

The boilers of three engines evaporate from 150 to 180 cubic feet per hour, and in running long distances it was necessary to provide for filling the tenders with water when the train was in rapid motion. Mr. Ramsbottom conceived the idea of placing a pair of cast iron troughs, about 1500 feet long, on a level part of the road; each end about five feet had an incline of one inch in 100. The troughs are 18 inches wide and 7 inches deep, and are placed one between the rails of each line and so that the water, 5 inches deep, stands at about the level of the rails. The tenders are made to hold about 15,000 pounds, and are provided with a rising water pipe, the lower end of which is fitted with an adjustable scoop 10 inches wide at the mouth; as the scoop meets the water the effect is the same as if, the scoop being supposed at rest, the water were in motion at the velocity of the train. In either case the water must rise in the pipe, and, if permitted to do so, to a height the same as that from which a body falls, in vacuo, in acquiring the velocity with which the scoop and the water meet each other. At 32 feet per second, or, rather, less than 22 miles an hour, this height would be 16 feet. The height from the water trough to the top of the inlet pipe is 7 feet, and a column of water of this height is just balanced, without delivery, at a speed of 15 miles an hour. The scoop dips two inches under the surface of the water, and at 22 miles an hour from 10,000 to 11,000 pounds are raised into the tender in 25 seconds. The delivery is practically the same at higher speeds, for although the velocity of the entering water is then greater, the time during which the apparatus is at work is diminished in the same proportion.

The Pennsylvania Railway have had a number erected on their different lines, and their advantages are, that the size and weight of the tender for running long distances may be reduced, the number of stoppages lessened and time saved. An express locomotive has thus been enabled to run the whole distance from New York to Pittsburg -438 miles-in one continuous run of 10 hours and 5 minutes, at an average speed of forty-three and one-half miles per hour.

Advantage of Metallic Lubricants. In a drying machine it was found impossible, even with the greatest care, to keep the arbors clean, so as to prevent the injury of the goods by grease-spots from the lubricating oil. The difficulty was entirely obviated by the use of metaline as a lubricant.-Chron. Ind.

C.

AN ACCOUNT OF AN EXPERIMENT MADE TO DETERMINE THE POTENTIAL AND ECONOMIC VAPORIZATION OF A BOILER IN THE ESTABLISHMENT OF MR. FREMERY, AT EUPEN.

By Chief Engineer ISHERWOOD, United States Navy.

In the appendix to a report of the discussions which took place between the engineers-in-chief of various French and Belgian "Associations for the Surveillance of Steam Boilers," at a meeting held in Brussels on the 8th, 9th and 10th of July, 1877, there is given, among other information of engineering interest, a description of an experiment made by Mr. Vincotte, Engineer-in-chief of the Brussels Association, on the 27th of February, 1878, with a boiler belonging to the establishment of Mr. Frémery at Eupen. The object of the experiment was to determine the economic and potential vaporization in this boiler, of water, with average semi-bituminous coal, under the conditions of daily use.

As the boiler was of a type not employed in the United States, and had an unusual and excessively small proportion of draught area above the bridge walls, with an unusual and excessively large proportion of heating surface to grate surface, it seemed to the writer that the data and results of the experiment, arranged and reduced in the manner adopted by the engineers of English-speaking countries, would be of" value to the readers of this JOURNAL. He has, therefore, recalculated all the quantities in English measures, and made from the French data. the following account, taking nothing from the original except the observed quantities therein given, and adding his own remarks:

BOILER. (See sketch).

The boiler was composed of two horizontal cylindrical shells, one so placed immediately above the other that the same vertical plane passed through the longitudinal axis of each. The least space in the clear between the shells was 9 inches, and they communicated by two vertical pipes of 233 inches exterior diameter, whose vertical axes were also in the vertical plane passing through the longitudinal axes of the shells. One of these pipes was placed as near as practicable to the forward end