RUNNING FREIGHT TRAINS.

By far the greater proportion of American locomotive engineers are employed on freight service. On most roads, the freight engines constitute from seventy-five to ninety per cent of the whole locomotive equipment. On this kind of service, locomotive engineers learn their business by years of hard practice in getting trains over the road as nearly as possible on time. On the best of roads, there is much hardship to be undergone, working ahead through every discouragement of bad weather or hard-steaming engines. The man who brings the most energy, good sense, and perseverance to his aid, will come out most successfully above these difficulties.

Every department of locomotive engine running has difficulties peculiar to itself. Every kind of train needs to be handled understandingly, to show the best results; but, I think, getting a heavy fast freight train on time, over a hilly road, having a single track, requires the highest degree of locomotive engineering skill. Therefore, I have selected that form of train as the first subject of description.

THE ENGINE.

The engine that takes the train over the road weighs 35 tons, and has 1,100 square feet of heating-surface for generating steam for cylinders 17 by 24 inches, which, through the pistons, transmit power to wheels 60 inches diameter. The engine is an ordinary eight-wheeled bituminous coal-burning American type of locomotive, built by one of our best makers, and well adapted for pulling any kind of train over a Western railroad.

THE TRAIN.

This consists of 20 loaded cars, making an aggregate weight of 450 tons.

THE DIVISION.

The physical character of the country, which is rolling prairie, makes the road undulatory,—up hill, then down grade, with occasional stretches of level track. Some of the gradients rise to sixty feet to the mile, extending over two miles without sagging a foot. Sound steel rails, well tied, are supported by a graveled road-bed, making an excellent track, and presenting a good opportunity for fast running where high speed is needed. The train is run on card-time, stopping about every twelve miles. Like all other Western roads, the stations are unprotected by signals; and the safety of trains is secured mostly by vigilance on the part of the engineer and other train-men.

PULLING OUT.

When the engineer gets the signal to go, he drops the reverse lever into the full forward notch, gives the engine steam gently, with due care to avoid breaking couplings, and pulls the sand-lever. A slight sprinkling of sand only is dropped on the rails, which keeps the engine from slipping while getting the train under way. A clear, level fire is burning over the grates before the start is made, and this suffices till the most crowded switches are passed: so, when the signal to start is given, the fireman closes the fire-door, and opens the damper; these duties not preventing him from keeping a lookout for signals.

HOOKING BACK THE LINKS.

As the engine gets the train into motion, the engineer gradually hooks up the links. This is not done by a sudden jerk as soon as the engine will move, with the steam cutting off short. He waits for that till the train is well under the control of the engine, hooking up gradually. Some men think that it is best to get the valves up to short travel as soon as possible, without reflecting that it is better for the motion to let the engine be going freely before hooking up short. I have often seen men coming into terminal stations with a heavy fire and the safety-valves blowing, and the engine toiling slowly along with the links hooked up to eight inches cut. In cases of this kind, a runner may better work the engine well down, so that the valve will travel freely over the seat. By doing so when the engine is working slow and heavy, there will be less wear to the valves, and less danger of breaking a valve yoke. It is only in cases where there is an advantage in saving steam, that benefit is derived from working the engine close hooked back. There is a right time for all things, and working steam expansively is no exception to the rule.

WORKING THE STEAM EXPANSIVELY.

At the right time, our engineer gets the reverse lever notched up; for he knows, that to obtain the greatest amount of work out of the engine, with the least possible expenditure of fuel, the links must be hooked back as far as can be done consistently with making the required speed. Some engines will not steam freely when run close back if they are burning coal that needs a strong draught. This is the exception, however, and most engines will steam best in this position; and many of those that fail to steam well cutting off short are not properly fired, or the draught appliances need adjusting. Most firemen who run with a heavy fire fail worst with engines that steam indifferently when hooked up. Engineers should give this their attention, and do every thing possible to make the engine steam while working with the lever as near the center notch as can be done while handling the train.

ADVANTAGE OF CUTTING OFF SHORT.

When the links are notched close towards the center, the travel of the valves is so short that they close the steam-ports shortly after the beginning of the stroke, at six, nine, or twelve inches of the piston’s travel, as the case may be, permitting the steam to push the piston along the remainder of the stroke by its expansive power. Steam at a high pressure is as full of potential energy as a compressed spiral spring, and is equally ready to stretch itself out when the closing of the port imprisons it inside the cylinder; and, by this act of expanding, it exerts immense useful energy, which would escape into the smoke-stack unutilized if the cylinders were left in communication with the boiler till the release took place. Suppose, for instance, that a boiler pressure of ten tons is exerted upon the piston from the beginning to the middle of the stroke, and is then cut off. During the remainder of the stroke, the steam will continue to press upon the piston with a regularly diminishing force, till, at the end of the stroke, if release does not take place earlier, it will still have a pressure of five tons. The work performed by the steam during the latter part of the stroke is pure gain, due to its expansive principle. If the steam is cut off earlier, at a third or fourth of the piston travel, the gain will be correspondingly great. With the slide-valve link-motion used on locomotives, the steam can not be held to the end of the stroke; but the principle of expansion holds good during the period the steam is held in the cylinders after the cut-off.

The observing engineer of any experience does not require to have the advantages of working his engine expansively impressed upon his attention. His fuel-record has done that more eloquently than pen can write.

BOILER PRESSURE BEST FOR ECONOMICAL WORKING.

There is a close and constant relation between the boiler pressure carried, and the useful work obtained from expansion of steam. The higher the pressure, the greater elasticity the steam possesses. The tendency of modern steam engineering is, to employ intensely high boiler pressure, expanding the steam by means of excellent valve-gear in steam-jacketed cylinders, so that it is reduced to low tension before escaping into the atmosphere, or into the condenser, as the case may be. Wonderfully economical results have been obtained in this manner,—results which can never be approached in locomotive practice while the ordinary slide-valve is used. But, while we can not hope to rival the record of high-class automatic cut-off engines, their methods can teach us useful lessons.

It is advisable to keep the steam constantly close to the blowing-off point. During a day’s trip, considerably less water will be evaporated when a tension of 140 pounds is carried, than will be required with a pressure of 100 pounds or under. And, where less water is evaporated, a smaller quantity of fuel will be consumed in doing the work. Running with a low head of steam is a wasteful practice, for several good reasons. The comparatively light pressure upon the surface of the water allows the steam to pass over damp, or mixed with a light watery spray, which diminishes its energy; since the wet steam contains less expansive medium than dry steam. It requires nearly the same expenditure of fuel to evaporate water at the pressure of the atmosphere alone, that it does to make steam at the higher working tensions: consequently, the work obtained by the expansion of the high-pressed steam is clear gain over the results to be obtained by working at a low pressure. This is a very important principle in economical steam engineering. Engineers who are accustomed to making long runs between water-tanks, when every gallon is needed to carry them through, know that their sure method of getting over the dry division successfully, is to carry steam close to the popping-point, pull the throttle wide open, hug the links close to the center, and see that no loss occurs through the safety-valves.

RUNNING WITH LOW STEAM.

There are engineers who habitually carry merely sufficient steam to get them along on time, under the mistaken belief that they are working economically. John Brown runs steadily, and takes as good care of his engine as any man on the A.&B. road; but he dislikes to hear the steam escaping from the safety-valves, and prevents it from doing so by habitually using steam thirty pounds below the blowing-pressure. The consequence is, that he always makes a bad record on the coal-list, compared with the other passenger men.

THE THROTTLE-LEVER.

In the interest of economy, the throttle-lever should be kept wide open when practicable, and the speed regulated by the reverse-lever. Experiments with the indicator have demonstrated beyond a doubt, that running with the throttle-valve partly closed, wire-draws the steam before it reaches the cylinders, whereby the initial pressure is materially reduced, and its power for expansive work seriously diminished.

MANAGEMENT OF THE FIRE.

The engine has moved only a few rods from the depot when the steam shows indications of blowing off; and then the fireman sets to work,—not to pile a heap of coal indiscriminately into the fire-box. That is the style of the dunce whose natural avocation is grubbing stumps. Ours is a model train, and a model fireman furnishes the power to keep it going. He throws in four or five shovelfuls at each firing, scattering the coal along the sides of the fire-box, shooting a shower close to the flue-sheet, and dropping the required quantity under the door. With the quick intuition of a man thoroughly master of his business, our model fireman perceives at a glance, on opening the door, where the thinnest spots are; and they are promptly bedded over. The glowing, incandescent mass of fire, which shines with a blinding light that rivals the sun’s rays, dazzles the eyes of the novice, who sees in the fire-box only a chaotic gleam; but the experienced fireman looks into the resplendent glare, and reads its needs or its perfections. The fire is maintained nearly level; but the coal is supplied so that the sides and corners are well filled, for there the liability to drawing air is most imminent. With this system closely followed, there is no difficulty experienced in keeping up a steady head of steam. But constant attention must be bestowed upon his work by the fireman. From the time he reaches the engine, until the hostler takes charge at the end of the journey, he attends to his work, and to that alone; and by this means he has earned the reputation of being one of the best firemen on the road. His rule is, to keep the fire up equal to the work the engine has to do, never letting it run low before being replenished, never throwing in more coal than the keeping up of steam calls for. The coal is broken up moderately fine, a full supply being prepared before the fire-door is opened; and every shovelful is scattered in a thin shower over the fire,—never pitched down on one spot. Some men never acquire the art of scattering the coal as it leaves the shovel; and, as a result, they never succeed in making an engine steam regularly. Their fire consists of a series of coal-heaps. Under these heaps, clinkers are prematurely formed; and between them spaces are created, through which cold air comes, and rushes straight for the flues, without assimilating with the gases of combustion, as every breath of air which enters the fire-box ought to do.

CONDITIONS THAT DEMAND GOOD FIRING.

Roads that are hilly require far more skillful management to get a train along than is called for on level roads, and the greater part of the extra dexterity is needed from the fireman. To get a heavy train up a steep hill, it is generally run at a high speed before reaching the grade, so that the momentum of the train can be utilized in climbing the ascent. Running for a hill is a particularly trying time on the fireman; for the engine is rushing at a high speed, and often working heavily. This ordeal must be prepared for in advance, by having the fire well made up, and kept at its heaviest by frequent firing. When the engine gets right on to the grade, toiling up with decreasing speed, every pound of steam is needed to save doubling, and steady watchfulness is required to prevent a relapse of steam; but the danger of the engine “turning” the fire is not nearly so great as it was when running fast for the hill.

HIGHEST TYPE OF FIREMAN.

The highest type of fireman is one, who, with the smallest quantity of fuel, can keep up a good head of steam without wasting any by the safety-valves. He endeavors to strike this mean of success by keeping an even fire; but it sometimes happens, that the closest care will not prevent the steam from showing indications of blowing off. When this is the case, he keeps it back by closing the dampers, or, if that is not sufficient, opens the door a few inches. Immense harm is done to flues and fire-boxes by injudicious firing.

SCIENTIFIC METHODS OF GOOD FIREMEN.

It is not necessary that a man should be deeply read in natural philosophy, to understand intimately what are actually the scientific laws of the business of firing. Mr. Lothian Bell, the eminent metallurgist, somewhere expresses high admiration for the exact scientific methods attained in their work by illiterate puddlers. Although they knew nothing about chemical combinations or processes, they manipulated the molten mass so that, with the least possible labor, the iron was separated from its impurities. In a similar way, firemen skillful in their calling have, by a process of induction, learned the fundamental principles of heat-development. By experiments, carefully made, they perceive how the greatest head of steam can be kept up with the smallest cargo of coal; and they push their perceptions into daily practice.

If an accomplished scientist were to ride on the engine, observing the operations of a first-class fireman, he would find that nearly all the carbon of the coal combined with its natural quantity of oxygen to produce carbon dioxide, thereby giving forth its greatest heat-power; and that the hydro-carbons, the volatile gases of the coal, performed their share of calorific duty by burning with an intensely hot flame. He would find that these hydro-carbon gases, although productive of high-power duty when properly consumed, were ticklish to manage just right, for they would pass through the flues without producing flame if they were not fully supplied with air; and, if the supply of air were too liberal, it would reduce the temperature of the fire-box below the igniting-point for these gases, which is higher than red-hot iron, and they would then escape in the form of worthless smoke. Our model fireman manages to consume these gases as thoroughly as they can be consumed in a locomotive fire-box.

THE MEDIUM FIREMAN.

John Barton is considered a first-class fireman by some men. He works hard to keep up steam, and is never satisfied unless the safety valves are screaming. He carries a heavy fire all the time; and, when the pop-valves rise, he pulls the door open till they subside, gets in a few shovelfuls more coal, closes the door till the steam blows off again, and repeats the operation of throwing open the door. This man has learned only the half of his business. He has got through his head how to keep up steam, but he has not acquired the more delicate operation of keeping it down wisely and well. Training with an intelligent engineer anxious to make a good fuel-record, will, in a few months, improve Barton wonderfully. Barton is the medium fireman.

THE HOPELESSLY BAD FIREMAN.

Behind him comes Tom Jackson, the man of indiscriminately heavy firing. Tom’s sole aim is to get over the road with the least possible expenditure of personal exertion. He tumbles in a fire as if he were loading a wagon, the size of the door being his sole gauge for the lumps. When the fire-box is filled to the neighborhood of the door, he climbs up on the seat, and reclines there till the steam begins to go back through drawing air: then he gets down again, and repeats the filling-up process, intent only on getting upon the seat-box with as little delay as possible. His firing is regulated by the appearance of the smoke issuing from the stack. So long as it continues of murky blackness, he reclines in happiness: when the first streaks of transparency appear in the smoke, he becomes unhappy, but gets up, and suppresses smoke-consumption by smothering the flames with green coal. If by any chance the engine steams so freely that the safety-valves blow, the door is jerked wide open, and kept there till she cools down. So the round goes. A hot, scorching fire, which heats the sheets and flues to their highest temperature, is continually being interrupted by the sudden cooling from a heavy load of damp coal, or a chilling current of cold air. No wonder, that, with such treatment, leaky flues, weeping stay-bolts, and pouring mud-rings, make their own protests, often reiterated on the pages of round-house work-books.

WHO IS TO BLAME FOR BAD FIRING?

The destruction inflicted upon the heating-surface of locomotives by the changes of temperature due to bad firing, should be charged to the engineer. The fireman commits the havoc, but the engineer is more to blame for allowing it to be done. Engineers often permit firemen to do their work badly rather than have words about it. But this is mistaken policy. A little firmness in the start will convince the worst of firemen that they must strive to fire properly, or quit; and a man who is indisposed to do his work well, deserves his walking-papers without delay. There is no kindness in retaining a hopelessly bad fireman on an engine. As a fireman, he is a continual loss to his employers; he is no credit to his fellow-workmen; and if, by the mistaken forbearance of engineers, he ever reaches the right-hand side, he will be a reproach to the engineering fraternity.