ing banking fires. My idea would be, therefore, that the allowance of coal ought to be increased to about $1.50. I do not put this as authoritative, but simply in such a form that Mr. Manning will be sure to reply to it.

Again, taking the case where the non-condensing engine is used in a dye-house. As the portion of the steam going through that engine devoted to work is only a small portion, you get 90 per cent. of that steam for use in the dye-house, and the 10 per cent. difference cannot be noticed, as I understand it. If that is the case, why is one-third the cost of the steam put in against that engine? How is that one-third arrived at? Is it merely a guess? Or is it really a proper allowance for that case?

Mr. S. J. Mac Farren.-While I am free to say that Mr. Manning's paper was a surprise to me, as one of those who thought that water-power was the cheapest, and while, of course, I do not question any of those conclusions for a moment, especially in cases where there is a large demand for large amounts of lowpressure steam, I would like to supplement the discussion by saying that I lived for some four years in Northern Mexico, where the whole table-land region, perhaps two thousand miles in length, abounds in water-powers, and where fuel is almost prohibitory in cost. Although there are timber-lands, transportation is excessive, and wood at the factory costs at the most favorable place I know of $3.50. I know of places where wood sells for $15 and $18 per cord, and coal and coke on the line of the Mexican Central Road is $18 or $20 per ton. For pure power purposes, water-power is often a great deal the cheapest.

Prof. Denton.-I would like to add one word. I know of a case at home right here, within fifty miles of New York. Those cases that the gentleman speaks of I know are very prevalent. But we cannot get any exact data about them. The case of water-power which I have in mind is a 75 H. P. plant at the Forest of Dean Mine Dock of Cornwall, on the Hudson River. Power is desired to operate a Cornish pump at the bottom of a mine about 300 feet deep. The ponderous nature of the pumprods, which run horizontally above ground for about a hundred feet, limit the speed to six revolutions per minute. Power is also required to operate an air-compressor.

Water is taken from a small lake, giving a fair surplus all the year round, and drives an overshot wheel forty feet in diameter at the rate of about eleven revolutions per minute. Spur gears of

2 to 1 ratio give the necessary motion to the pump-rod and aircompressor. The cost of the wheel is about the same as that of a steam-engine and boiler fitted to the work. Coal would have to be drawn to the mine up the Palisades, and over such a distance that its cost would greatly exceed that of the water. This case is also remarkable from the fact that a turbine-wheel could not be economically applied, as it would have to run so fast that to gear down to the six revolutions required for the pump would involve an impracticable application of gearing.

Mr. Manning.*-The allowance of 12 pounds for running the compound engine, including the banking of fires, is taken from the engines of the Nurse Mills, which were tested very carefully by reliable parties, and the cost came inside of that. That was with new boilers and everything in good working order. The pressure of steam, as I recollect it now, was 120 pounds. That has been exceeded. Better results than that even have been obtained. The next point as to evaporation of the boiler requiring nine pounds and over, that is not a difficult feat by any means. A properly designed boiler will evaporate over ten pounds of water from feed of 100 to 120 degrees to steam of 100 pounds. If the gentleman is dubious on the subject, if he will come up and see me some day, I will show him how it is done. The figures were based largely on my experience at the Amoskeag Mills. The difficulties of obtaining exact cost, except from the known evaporation of the boiler by boiler test, and the weight of water accounted for in the engine, comes in from the fact that the whole steam plant is run practically by one pipe. There are several large pairs of engines, two large presses, and one large compound and other small engines, all receiving steam from the same pipe and always in operation at the same time, besides very many other uses, so that it is impossible to get a test there from the measurement of the water evaporated, the coal to do it, and the performance of any one engine. The figures given, I think, can be pretty readily substantiated from the fact.

Prof. Denton.-The allowance of $3.50, on page 505, Mr. Manning, is that from a measurement or a guess?

Mr. Manning.-No, sir, that is not a guess. That is the credit given from the actual work done by the steam.

Author's closure under the rules.

CCCXXXIII.

THE OLD LOCOMOTIVE "SAMPSON."

BY D W. ROBB, AMHERST, N. S.

(Member of the Society.)

Ar the Albion coal-mines in Pictou County, Nova Scotia, may be found a curious collection of old machinery, mostly lying rusty and disused, which, to the engineer of to-day, recalls the times of Watt and Stephenson, and the early days of the steam-engine. While making a recent visit to this place, the writer was shown many mechanical curiosities, notably three old locomotives, built by Timothy Hackworth in the shops of the Stockton and Darlington Railway, in England, in the year 1838; also a condensing beam engine, built about 1828, with ponderous flywheel and square driving shaft. A blowing cylinder, used to supply air to a foundry cupola of ancient construction, still in use, is connected with one end of the beam, the crank shaft being connected with the other end and the steam cylinder nearer the center of the beam. Steam for this engine was furnished by an old-fashioned egg-shaped boiler. The working pressure did not exceed five pounds above the atmosphere, and the water was supplied by gravity from a tank placed a few feet above it. Leaks were repaired by simply fitting a plate over the leak, in the inside, well packed with potatoes or horse dung, the very moderate pressure rendering rivets or bolts. unnecessary. One of the locomotives referred to, the "Sampson," was in use as late as the year 1882, is in a fairly good state of preservation, and, as it is a good example of the first English locomotives, a brief description may not be uninteresting. As previously stated, it was built at the repair shops of the Stockton and Darlington Railway, at New Sheldon, Durham Co., England, and was brought out with two similar locomotives, in 1839, to run on a railway, built for the Albion mines, to convey coal from its pits at Stellarton, to Pictou Harbor, a distance of six miles. As will be seen from the illustration (Fig. 114), the "Sampson" has three pairs of driving wheels, coupled in the usual manner, and not differing very much in appearance from the driving wheels of the modern

"mogul" locomotives. These wheels consist of a cast-iron center and an outer rim, also of cast iron, twelve wooden plugs being

The

driven between the center and rim to hold the rim in place. The tires are of iron or steel, shrunk on in the usual manner. axles, which are five and five-eighths inches in diameter, run in

FIG. 114.

ordinary journal boxes, bolted to brackets made of boiler plate, which are riveted to the shell of the boiler (Fig. 111). The boiler is a plain cylindrical shell, fifty-four inches in diameter, and about thirteen feet long, containing a single return flue, twenty inches in diameter; one end being fitted with grates was used as a furnace. The products of combustion following the flue to the front end of the boiler, were then returned direct to the smoke stack, which is at the rear end of the locomotive (Fig. 112). The cylinders and driving gear are at the front end of the locomotive, and the driver's place was at the front, so that he could keep a good lookout ahead. The fireman was stationed at the rear.

The cylinders (153" dia. x 18" stroke) are vertical, resting on cast-iron box-like frames, forming part of a bonnet or hood which partially encloses the valve gear, pumps, throttle and reversing levers and other working parts. The cross heads, instead of being guided by slides in the ordinary way, have an arrangement of levers and sliding block (Fig. 113). That this device caused very little friction is shown by the fact that the original pins and brass bushes in the levers and sliding block are still in place, and show very little wear, after forty years of almost constant use. The valve gear consists of four eccentrics, attached to the axle to which the cylinders are connected; the eccentric rods extending up into the hood on the front end of the boiler, have forked ends which engage the pins of a rock arm, which is connected with the slide valves; these eccentric rods are controlled by the reversing lever, respectively engaging or disengaging them for the forward or back ward motion (Fig. 112). The feed pumps, two in number, are connected with the eccentric rods, and were thus brought within the hood in full view of the driver; in fact, this arrangement of cylinders and valve motion gave the driver a convenient oversight of all the working parts of the engine while in motion, and without leaving his place; but, strange to say, he was compelled to go outside to ascertain the height of water or pressure of steam, the water gauges and steam gauge being located on the side of the boiler. The steam gauge consists of a spring scale attached to the lever of the safety-valve. The pressure of steam did not exceed forty pounds, the spring scale being graduated to fifty. The exhaust steam after leaving the cylinders was conveyed within the shell of the boiler (Fig. 112) to the smoke-stack. The reason for thus reheating the exhaust steam is difficult to understand. Probably the idea was that the heat of the exhaust could be utilized within