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UNION MEETING AT NORFOLK, VA., NOV. 29, 1898.

mailing lists were all destroyed, and this is the only method of assuring all subscribers the receipt of subsequent numbers.

Mr. Fred H. Colvin, vice president of the company, writes under date of December 15, 1898: "We are hard at work and are getting in shape fairly well in our new quarters (95 Liberty St.), and from present appearances will have the January issue out on time, but you will appreciate the amount of work this necessitates."

The old saying, "you can't keep a good man down," will be exemplified in the experience of Locomotive Engineering, for it is predicted that in the future this publication will be better than ever.

Torpedo Boats a Failure. According to the official naval reports, the torpedo boat in warfare is not so formidable as was supposed.

Wherever a Spanish torpedo boat ventured to become aggressive, it ceased to be aggressive by either going to the bottom or to the nearest beach, and the American torpedo boats had but little better experience, whenever they were confronted with fighting ships.

The report of the Engineer-in-Chief says: "It is greatly to be regretted that the torpedo boats cannot show the same excellent record for their machinery, but it is a sad fact that nearly every one has had some accidents, and the machinery of some at the close of the war was in a condition which can only be described as horrible — where boilers were burnt, cylinder covers broken, pistons and valves stuck, and everything in bad shape. This condition of affairs seems attributable to two causes the absence of trained engineering supervision and the use of the boats for duty to which they were not adapted."

LOCOMOTOLOGY.

D. R. M'BAIN. *

The "D 8" This device was designed Engineers' to do away with the surge Equalizing of the air in the train line, Discharge Valve. which, with the old " B 11" or "Three-way cock" was very annoying on long freight trains, as when the engineer opened the train line with his "B 11" or " Three-way" to apply the

*Mr. D. R. McBain, President of the Traveling Engineers' Association, has agreed to conduct an educational department in the LOCOMOTIVE FIREMEN'S MAGAZINE, to be known as "Locomotology." Under this head Mr. McBain will write articles on technical topics, questions and answers on the locomotive and

air brake, and in the "Question Box" answer such

questions as are sent to him by interested enginemen.

Mr. McBain needs no introduction to the readers of

the LOCOMOTIve Firemen's Magazine, as his interesting and instructive articles have long been a source of pleasure and profit to them.

brakes the air would rush from the rear end toward the engine, and just about the time the reduction was beginning to take effect the engineer closed his "B 11" or " Three-way," which at once stopped the flow of air from the train line. The rush of air in the train line from the rear end would strike up against closed engineer's valve raising the pressure at that point and releasing the brakes, just about the time the brakes on the rear end were beginning to do business — after which the trainmen did the chaining up. Another purpose in this design was that it in a measure would make up for lack of judgment on the part of the

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engineman, i. e., by limiting the opening through which air must pass to the atmosphere in service application. The "B 11" or "Three-way" left that important matter in the hand of the engineer, and when the new quickaction tripple valves came into use generally, the B 11" or "Threeway" became very unpopular on account of the liability to operate the emergency when only a service application was desired. Skillful men could, nevertheless, handle the B 11" or Three-way" without any of the evils above related. But there were skillful men and men that were otherwise, more of the latter unfortunately, than of the former, as the air brake on freight trains was then but in its infancy, so that the freight men and "Westinghouse" were pretty near strangers.

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The "D 8" was a success, and we will now give a plain description of same as we see it.

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The equalizing discharge feature of this valve lies in the "piston 17," the valve on end of stem of same and the "chamber D" and "small reservoir" in combination - always consider the chamber D and small reservoir as one. When the train line is charged up to the desired pressure, always figure that chamber D" pressure is the same, so that we have the valve on the end of the stem of piston 17 seated and the exhaust port to atmosphere closed. Wishing to make service application the engineer moves handle of valve to the right, opening a way to atmosphere through preliminary exhaust port from chamber D, allowing that pressure to be reduced five pounds, the pressure in train line then raises piston 17 off its seat opening the exhaust port to atmosphere, through which the train line air escapes until that pressure is reduced to a point equal to that in "chamber

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In releasing the brake, if the handle of engineer's valve be turned to the extreme left, it opens direct communication through a 34 opening between main reservoir and train line. however, the handle of the engineer's valve is only moved as far as running position to the left, the air in passing from the main reservoir to the train line must flow past the excess pressure valve. This valve is held to its seat by a coil spring in the train line capable of resisting a pressure of twenty pounds in the main reservoir, so that by releasing in running position, it is only possible to raise the train line pressure to a point equal to twenty pounds less than that of the main reservoir.

In starting to pump up an empty engine, if the handle of engineer's valve is placed in running position, the main reservoir pressure (the red hand on gage) will raise about twenty pounds before the spring behind excess pressure valve will allow same to open to the train line, and the red hand will lead the black one up the face of the gage about twenty pounds, until the desired train line pressure is obtained and the excess is secured.

In running position only one small port conveys air to "chamber D;" at full release an additional one of same size is opened,

Sometimes when brake is released on light engines the "piston 17" will raise and let the air pass out of train

line to atmosphere through service exhaust port. This is because the "chamber D" having small inlets for air does not fill as quickly as does the train line, in consequence of which the "piston 17" is raised and the exhaust opened. In making an emergency application the handle of the engineer's valve is turned clear around to the extreme right, which makes an opening between train line and atmosphere of about 3/4 inch area.

Here is a peculiar case of Snap Ring cylinder packing failure on

Packing.

heard her blowing badly. Getting up on the engine he told the "hostler" to back her outside again, which was done. At this time she had fifty-five pounds of steam. The packing was tried, and both sides were then blowing badly. The engine was put in the house, the cylinder heads taken off, and the packing examined. The rings looked all right, except that they did not reach the wall of cylinder at top by nearly an eighth of an inch. It was decided, however, to take the old packing out and put in new, which was done, and

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a locomotive: A 17 x 24 inch passenger engine came out of the shops, after receiving general repairs, and, after being "broken in" on freight, went on her run, a fast local. After she had made about 20,000 miles, the engineer began to complain that she was losing her "snap," and that she would not do her work as well as she did at first, and also that she was getting to ride harder every day. However, he did say that if he dropped her down" a notch and "eased the throttle off," she was all right. The valves were "run over" and that part of the machine was found in good shape, but not wishing to miss any possible cause for the trouble, the valves and seats were refaced and put The Chaumont (France) railway viaduct, 175 feet in in the best condition possible. The cylinder packing-snap ring-was ex amined on several occasions, only to be pronounced all right.

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A THREE-STORY BRIDGE.

height and 1895 feet in length.

the result was an absolute cure. The cause of the trouble was that when the engine was in the shop, the packing that was in her was too good to throw away, and at the end of about 20,000 miles' run, its usefulness had passed away by wear, to the extent that, when the steam pressure was low, it would not "set out;" in consequence of which the steam blew through into the wrong end of the cylinder.

Why the engine "lost her snap" on the road was because, when working at

'six-inch cut-off," by the time the piston had traveled "half stroke," or a little further, the pressure in cylinder was reduced by expansion to a point where it would not hold the rings out against the walls of cylinder, the result of which was that the steam blew past and acted against the piston for the balance of the stroke, thus decreasing the efficiency of the engine, and causing the hard riding complained of by the engineer.

That part of the case where the engineer said she rode easier and did better when he worked her a notch lower on the quadrant, I think can be explained as follows: When he worked her down a notch lower the live steam would, of course, follow the piston a little further, and consequently was not reduced by expansion early enough in the stroke to cause much if any of the evil results as above stated. The moral in this would seem to be that the time to try "snap ring "packing is when the steam pressure is low.

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the front port, after that end of the cylinder has been filled with steam, the eccentric gave way and did not move the valve enough to open the exhaust from that end. Then, when the piston came back on the return stroke, and came in contact with the steam that was in the front end of the cylinder, the valve being held down by the pressure of the steam chest on its back, makes it impossible for the piston to force the steam out of the cylinder, back through the port into the steam- chest, as the only surface exposed to the steam in the cylinder is that portion of the bottom of the valve covering the port; so that if the pressure in the steam chest was 80 pounds it would require about 560 pounds in the front end of the cylinder to raise the valve against the steam chest pressure, as the area of the valve exposed is at a ratio of about seven on top to one on the bottom. It will be seen from this, why cylinder head breaks; or, if it is the back end of cylinder that is full of steam, why keys shear or break altogether, as is often the case.

A Good

Hot Pins.

Take one pound bar of yel"Dope" for low soap and one pint of valve oil. Melt the soap in the valve oil, after which mix in two pounds of clean white lead and stir well. If pin is very hot, remove the feeder from the cup and put a small quantity of the compound down on the pin, after which replace the feeder or cup, as the case may be, and fill the cup to about one-quarter with the compound, and the balance with engine oil. That which you let on to the pin direct will glaze the rubbing surfaces over, and that which you put in the cup itself will make oil about the right specific gravity to stand the additional heat in

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