By making the return trip "ahead of No. 50 until overtaken" it relieves the latter train of ascertaining whether the extra has gone or not, and permits the extra to run ahead of No. 50 or follow it, as circumstances may determine.

80. Sections Not Specified.-"Train No, 43, second class, going west receives order No. 1 at C. T. Tower to meet No. 38, same class going east at Birch. No. 38 has absolute right of track over train No. 43. Upon arrival of No. 43 at S. X. (an intermediate station) it receives order No. 2 which reads as follows: Train No. 43 and 1st No. 38 will meet at S. X. instead of at Birch.' Now I would like to know if train No. 43 can proceed to Birch for 2d No. 38 without receiving another order, or does order No. 2 supersede order No. 1."-W. A. R., Keating, Pa.

If

Answer. We believe it is the rule on almost every road that when a train is run in more than one section each section shall be specified in train orders. This is required whenever it is known how many sections are to run. If, however, for any reason, they are not so specified, the mention of a train includes all sections. this is the practice on the road from which this question came, we should say that a strict construction of the rules would permit No. 43 to go to Birch for 2d 38, but inasmuch as it is an unusual method of handling trains we should not want to go, if we were running No. 43, without being satisfied that we were right.

Several unanswered questions might enter into the case. When order No. 1 was issued was there more than one section of No. 38? If so, why did not the order specify that No. 43 would meet 1st No. 38 or 1st and 2d No. 38, instead of saying "No. 38"? Assuming that there was but one No. 38 when the meeting point was made at Birch, and only one section signed for the order, what assurance have we that 2d No. 38 is going to wait at Birch for No. 43, inasmuch as the 2d section was apparently created after order No. 1 had been issued? The order is not strictly in accord with the Standard Code in that the first order directed No. 43 to meet No. 38 at Birch, which indicated only one section. The second order directed it to meet 1st No. 38, which indicated that there was more than one section. The train to be met at S. X. had a different name from the one to be met at Birch, therefore the term "instead of" did not strictly apply.

We should suggest this form of order in case additional sections of No. 38 were to be run:

Locomotive Running and Repairs.

Answers by G. W. Wildin.

[In the second column on page 771 of the December number, in Mr. Wildin's answer to Question 42, a formula was given as follows: d2×S×P-D. This should have been d2xSxP-D. The cause of this error was the failure of the compositor to distinguish the difference between d2 and d, and the failure of the proofreader to notice the error. errors are alike annoying to the Editor and technical contributors.-Ed.]

Such

=

PLAN 33000

gives the

horsepower developed in one cylinder of a locomotive only. But the formula as given in the October issue of the MAGAZINE took into consideration both cylinders as follows: PLAN X2 horsepower, In other words, it 33000 is assumed that the work done in each cylinder of a locomotive is the same, Using the first formula above, we get the work done in one cylinder; then if we multiply the result by two, as in the second formula, we get the work done in both cylinders, or the total horsepower.

44. Formula for Calculating the Tractive Power of a Locomotive.-"I would like to have given, in the department 'About Locomotives,' a formula for calculating the tractive power of a locomotive in pounds."-A. B. R.

Answer.-The universal formula for calculating the tractive or pulling power of a lod2 x S x P comotive is as follows: T, in D which d represents the diameter of one cylinder in inches, S the length of stroke in inches, P the mean effective pressure in pounds per square inch, D the diameter of the driving wheels in inches and T the trac

45. Giving the Valves on a Locomotive Lead. "Can you or can you not give the valves of a locomotive lead by setting the eccentrics at right angles to the crank pin and lengthening the blades the required amount, the crank pin being either on the forward or rear center? If not, why not? We know the books tell us that lead can be changed only by adjusting the eccentrics on the axle, but since the question is in dispute, would like your opinion."A. H. W.

Answer. The books are correct. You can not adjust valve lead on a locomotive by changing the length of the eccentric blades. You can, it is true, with the crank pin on forward center and the eccentric on top quarter, so lengthen the forward motion eccentric blade as to give the desired 1-32 in. or 1-16 in. port opening, but when the driving wheel revolves one-half revolution the eccentric will be on lower quarter. In this position it will be necessary to shorten the forward motion blade in order to obtain 1-32 in. or

1-16 in. opening of the back steam port. In other words, if we adjust the eccentric blades so as to obtain lead for the front steam port when crank pin is on forward center, we blind the back port when the crank pin is on rear center. All that we can accomplish by adjusting the blaues is to get what we call a "square" engine, and nothing more.

46. Generation of Steam in a Locomotive Boiler.-"How is steam produced in a locomotive boiler?"- W. B. C.

Answer.-Steam is produced in a locomotive boiler the same as in an open vessel-by a boiling process; the only difference being, in one case the steam when generated is confined and is capable of be

ing used to do effective work, while with the open vessel the steam as it rises from the water escapes into space. The fire upon the grates causes intense heat in the firebox and tubes, and as one side of the firebox sheets, and also the outer surface of the tubes, is exposed to water, a boiling action is the result, the steam rising to the surface filling that portion of the boiler not already filled with water.

47. How Steam in a Locomotive's Cylinders Draws a Train.-"How is steam applied in a locomotive to draw a train?"- W. B. C.

Answer.-Steam is generated in a locomotive boiler and stored as explained in question No. 46. When it is desired to start a train the throttle valve is lifted by pulling on the throttle lever. This action allows the stored steam to escape from the boiler through the throttle valve opening to the dry-pipe, thence through the dry-pipe and steam pipes to the steam chests. As the valves move and uncover the steam ports, the steam in the steam chests forces itself into the cylinder, entering between the cylinder head and piston, forcing the piston away from the head, thus transmitting motion to the crank pin, causing the wheels to turn and the train to move.

48. Pounds of Water Evaporated per Pound of Coal.-"How many pounds of water should be evaporated per pound of coal in a locomotive?"- W. B. C.

Answer. The number of pounds of water that may be evaporated per pound of coal in a locomotive boiler depends entirely upon the quality of the coal used. With a fair quality of bituminous coal an evaporation of 7 to 8 pounds of water per pound of coal is considered good locomotive performance. With anthracite or hard coal the evaporation is even lower than the above, and would be placed between 6 and 7 pounds.

49. Effect of Bad Joints in a Locomotive Front End. “What is the effect of bad joints or leak about the smokebox, also a leaky pipe inside the smokebox?"- W. B. C.

Answer. The effect caused by either of the above defects is always a bad steaming engine. When the exhaust steam escapes from the exhaust nozzle through the stack to the atmosphere, it carries with it a considerable portion of the gases in the front-end, thus producing a partial vacuum in the smokebox. This vacuum, if all steam joints and front-end joints are

tight, will be filled with gases from the firebox, which in turn are replaced with other gases generated by further combustion, this further combustion being made possible because of fresh air passing up through the grates. Now, if we have leaky joints in the front-end, or the steam pipe joints are leaking, the steam from the leaky pipes and the air from outside the smokebox will take the place of the gases removed by the exhaust jet and no room is left for the gases from the firebox, consequently no air can enter through the grates and combustion practically ceases.

50. Staying Firebox Sheets to Withstand Steam Pressure. "How are firebox sheets braced to withstand the steam pressure?"-A. B. C.

Answer. The side sheets and door sheet, also the lower portion of back tube sheet, are secured by staybolts, usually spaced about 4 inches apart. The door sheet is stayed to the boiler head, the lower portion of the tube sheet is stayed to the throat sheet, and the side sheets to the boiler side sheets. The crown sheet is braced in two ways-one called "radial stay" and the other "crownbar" bracing. "Radial stay" implies that long staybolts are used to hold crown sheet and roof sheet together, and are located radially with the curve of the roof sheet. "Crownbar" staying means that heavy bars are placed across and over the crown sheet with ends resting on the side sheets of the firebox, and the crown sheet is secured to these bars by means of bolts.

See October issue of MAGAZINE, Questions 8 and 9, for definition of a crownbar and staybolt, respectively.

51. Superheated Steam. "Please explain the process of superheating steam for use on a locomotive; also its advantages and disadvantages."-R. H. C.

Answer. The superheating of steam to effect economy in locomotive performance is not a common practice on American railways. The subject of superheating is being studied to a considerable extent in European countries, and a number of superheaters have been applied to locomotives on the Prussian State railways. In the main, superheaters as applied to locomotives consist of a coil of pipe of considerable length, located in the smoke

Comfort one another,

For the way is often dreary,
And the feet are often weary,
And the heart is very sad;

And there is heavy burden bearing,
When it seems that none is caring

box and through which steam from the throttle valve must pass on its way to the steam chests. This coil of pipe, or superheater, is kept heated to a very high temperature by exposure to the hot gases passing through the tubes. It is claimed that steam from a boiler pressure of 175 pounds passing through one of these superheaters will be increased in temperature about 250° F., which would mean about 25 per cent. increase in the horsepower of the boiler. The advantage to be gained is in high temperature of steam entering the cylinders, allowing greater expansion with less loss of energy due to condensation. It is claimed that by superheating steam in a locomotive as great or greater economy can be had than by compounding.

The disadvantages encountered in superheating are the cost of construction and maintenance of the superheater and the difficulty experienced in lubricating properly the cylinders and valves because of the high temperature which they attain.

52. Diameter of Driving Wheels; Their Effect on the Speed of a Locomotive.-"Why can an engine with large drivers run faster than one with small drivers?"-R. R.

Answer. The locomotive with the large driving wheels is carried over a given distance with a great many less strokes of the piston and revolutions of the drivers than the locomotive with smaller wheels. For instance: An 85inch driving wheel makes 237 turns in a mile, while a 60-inch wheel makes 336, a difference of 99 revolutions or about

42 per cent. Understand, this means an increase of coal and water consumption of about 42 per cent., as well as the same increase in piston speed, and tendency of bearings to heat.

We might put this matter in another way, and say the locomotive with small drivers runs faster, but does not cover distance so fast.

Besides the tendency of bearings to heat on locomotives with small drivers, when driven at a high speed, there is another serious feature-that of high piston speed which means non-effective steam consumption and distribution.

A

WAY out in the very heart of the great staked plain, where the cold wind in winter, that sweeps down from the Northland, moans around it, and the sun of summertime shines bright and hot, lies the little station of Rogers. And yet, small as it is, Rogers is in one way an important town on its line of road, for the weary traveler, worn out and dusty from hours of riding, feels a sense of relief when the brakeman on the express, which once a day creeps over this level plain, calls out, "Rogers! twenty minutes for dinner."

And as each in their turn step onto the platform, they see, besides the depot, only one lonely house in sight, and then they hurry in and seat themselves at the long tables filled with tempting eatables.

At the time I write one of the tables was usually waited on by a girl, slender and fair, with hair of the softest brown worn loose with only a bow at the back. Her eyes, like her hair, were brown, and in them one could see a longing look for something that the heart had hidden for years. Her voice, though uncultured, had about it that soft, sweet southern accent one loves to hear.

The road men called her Jennie, while the cowboys who came riding over the plain shortened it to "Jen," and vied with the road men for her favors. But to only one, Terry Donavan, did she show any preference, to the others she showed no partiality whatever, but moved along in her simple duties as silent as the great lone plain around her.

But one day when the express stopped for dinner and the passengers came hurrying in, she saw a young man, tall and dark, dressed in simple black, who smiled and thanked her as she handed him his coffee and then watched her continually as she moved about the room. And then, when the train went puffing away toward the southwest, it left him standing on the platform gazing after it till it disappeared in a cloud of sand and smoke over a swell in the plain.

An hour later, as she went out on the platform, she saw him walking down the

track with his hands behind him, seemingly in deep thought. He turned as he noticed her, and came to where she was standing.

"I have been wondering," he said, "just what life must be out here on this great rolling plain."

"Just what you see," she replied, "nothing, nothing, nothing to look forward to, nothing to look backward at, only a long stretch of years of nothing. Today comes and goes, then tomorrow will come, and like today it will contain nothing."

"But it is home," he said, "and where home is, there the heart is."

"Yes," she answered, "it is home, the only one I have ever known, but my heart is not here, for the Master who made all never made a more lonely home than this. But," she continued, "I've heard the road men say that away beyond the edge of this soap plant plain is another country, where all is gay and fair, where men and women are learned, where they have colleges and churches and there is always someone that knows something to talk to, and I have longed so many times that some day I might leave this lonely place behind me, and go 'way on the express to that other land and taste its joys. The one thing in this world I most long for is that I may some day learn as others who go through here have learned. Do you live back there?" she asked.

And he answered, "Yes, I am a minister of the gospel and my home is in Chicago." And then word by word he drew out her life's story.

"I am eighteen years of age," she said; "my mother died soon after my birth, and my father gave me to these people. They have brought me up and I have worked here day after day, receiving for what I have done just what I eat and wear. They have educated me only as far as they know; beyond this my knowledge of the world is a blank. They won't send me to college for they need me here to drudge. The common education I have received is not enough for me. I desire to learn more of the great rushing world that lies beyond this dreary plain."

In all his five and twenty summers,