by Eric Flint
Theoretically, compound working increases thermal efficiency (EB11/R). However, in actual practice, "it was discredited for reasons of higher first cost and troublesome maintenance problems." (EA)
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Articulation. The locomotive data table makes reference to "articulated engines." These have essentially two separate but flexibly connected engine-and-wheel sections, each mounted on a bogie. This is essentially a way of having the advantages of a long wheelbase (high tractive effort with low load per axle) without the disadvantage (being "curve-shy"). EA says that articulation "made possible machines of extraordinary size and length." The modern EB is also approving, and mentions the 600 ton articulated "Big Boy" 4-8-8-4 (135,400 pounds traction; over 6,000 hp at 75 mph).
In the original "Mallet" configuration, the boiler was rigidly attached to the rear "power bogie," and the front power bogie pivoted on the rear one. In the "Meyer" configuration, both power bogies were connected by pivots to the overhead boiler. And in the "Garratt" configuration, the boiler was in-between, rather than above, the power bogies. (Self; *Gordon 97).
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Superheating. EB11/R commented that the "application of superheaters to locomotive work" is "exceedingly promising." The steam which is initially generated by the boiler is what is called "wet steam," because it contains water droplets as well as water vapor. If more heat is applied, the temperature remains constant until the water is all evaporated, and then you have dry steam. And if you heat that even more, the temperature rises, and you have superheated steam.
It has two advantages. First, it avoids wasting water by delivering it to the cylinders in liquid form. (It is only the compressed water vapor which, by expanding, moves the pistons.) Secondly, superheated steam occupies a greater volume than wet steam of the same pressure. That means that you can use bigger cylinders, which in turn allows you to either increase power, or reduce the boiler pressure (and fuel consumption). (Netherwood)
EA says that superheating increased horsepower and reduced fuel costs by about 25%. Unfortunately, EB11/R doesn't explain how superheating was carried out, and EA contents itself with a cryptic, "this mechanism returned the steam through the fire tubes of the boiler for reheating."
In a fire tube superheater, the upper rows of fire (hot air) tubes are made large in diameter. The wet steam from the steam dome is fed into narrow tubes which enter the top row of superheater tubes from the smoke box end, make a U-turn at the firebox end, and exit. They may then enter and leave a second or third row of superheater tubes the same way before delivering the now superheated steam to the steam chest. (GW10).
For superheating to be practical, the cylinder and boiler must be able to resist the corrosive effect of superheated steam, and the cylinder lubricants must remain functional. Heavy mineral oils (in short supply in Grantville) were needed for lubrication (EB11/SE 829). The necessary advances in the iron and oil industries will take some years, which is why I see superheating as a second generation feature.
Other Locomotive Design Features
Headlights, Bells and Whistles. These made travel, especially at night, safer.
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Cowcatcher. Cheaper than fencing the whole line, and helps to clear track of debris or light snow.
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Sanders. These were used to release sand in front of the wheels, to increase adhesion (especially when trying to start a train). EB11/R (p. 646) says that the sand is blown onto the rail by a steam jet. A sand box and sand pipe are shown by Alexander PL79 for a 1887 2-8-0 class R; here, the sand seems to just drop down. Sanding increases adhesion to about one-third (Clarke, 121).
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Water quality. Minerals in the water can deposit on the boiler pipes. This fouling slows heat transfer and can result in tube failure. Impure water may also foam up if the boiler suddenly loses steam, intruding into the cylinders and damaging them (White, GW14). The solution is to purify or treat the water, either before loading it in the tender, or with an on-board system. Or you can "blow down" the boiler regularly, to clean out the scale.
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Tenders. Fuel and water can be carried behind the locomotive in a "tender." A typical one might carry 3,000 to 7,000 gallons of water, and 5 to 10 tons of coal. (Connor, 91).
Water was originally conveyed by leather or canvas hoses; these were replaced by rubber ones in the 1850s. (White 223).
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Water injector. Alexander PL79 shows the use of a steam jet (Giffard, 1859) to force water into the boiler. Previously, axle-driven pumps were used (Nock/RE, 150; Clarke, 116).
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Feedwater heater. Exhaust steam may be used to warm the water before it enters the boiler. (NOCK/RE, 150; EB11/SE," 841).
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Mechanical stokers. A fireman can shovel only 2-2.5 tons an hour; this limited steaming capacity. Mechanical stokers could handle ten times as much coal. (Sinclair, 673; Gordon, 48; EB11/B 150). The EA article shows one type, a screw conveyor for moving coal from the tender to the grate. The fireman could use steam jets to redistribute the coal on the grate.
We will need mechanical stokers only after we are building locomotives which are large enough to overburden a fireman. Even then, since labor is cheap, we might want to first experiment with a two stoker firebox.
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Integral tank. Instead of using a tender, the locomotive may carry its own water and coal. Such a "tank locomotive" is more efficient (the stored water is preheated as a result of proximity to the boiler), able to move in either direction (a tender can't be safely pushed backward, at least at high speed), more compact than the engine-and-tender combination, and capable of exerting a greater tractive force (because the weight of the fuel and water contributes to the weight on the driving wheels).
A "tender locomotive" design is better if the locomotive must go a long distance without refueling, because the storage capacity of a separate tender is greater than that of a "tank locomotive."
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Suspension Systems. In the first locomotives, the driving axles were mounted in a rigid frame. Alexander describes an improvement; in the 1837 Hercules (PL8), the driving axles were placed in a truck of their own, the center of which was connected to the main frame of the locomotive.
In the bogie holding the leading wheels of the 1842 Mercury (PL13) the axle boxes hung from springs, which dangled from a bolster, which in turn was attached underneath the front of the engine. Apparently, these axles could move up-and-down if the track was uneven. Alexander says that the driving wheels were also equalized, without providing details.
Ellis (113) also discusses bogie design, and makes the key point that it is desirable to provide a "three point suspension." How is this accomplished? Ellis doesn't say. If there are two driving axles, then the springs on each left side are connected by one equalizing lever, and those on the right side by another. These levers are in turn connected to the bottom of the locomotive frame, one on each side. The leading bogie, on the other hand, was centrally connected to the bottom of the locomotive. The three connections form a triangle, which makes it easier for the locomotive to "stand" on uneven road. (Clarke, 4, 114).
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Insulated cylinders. Some steam is lost through condensation in the relatively cool cylinders. White (207) says that "the insulation of cylinders might appear to be obvious for reasons of thermal economy, yet, from existing evidence, it was not employed regularly until the 1850's." This is an example of one of the hundreds of fine details of locomotive design which are unlikely to be spelled out in the books available in Grantville.
Conclusion
In Action Comic #1, published in 1938, readers were told that the new hero, Superman, "could run faster than an express train" (i.e., more than 80 mph). Later, he was described as "more powerful than a locomotive" (which by then could muster 3,000 hp). The point of mentioning all this is not, of course, to quantify the superpowers of Superman, but to observe that the locomotive was thought to e
pitomize both speed and power.
With its ability to haul great loads at high speeds, across vast distances, the USE locomotive will be, in the words of Jessamyn West, "a big iron needle stitching the country together."
Select Bibliography
*Alexander, Iron Horses: American Locomotives 1829-1850 (1941)(all refs are to plate #).
*[EA] "Railroads," Encyclopedia Americana
*[EB11] Encyclopedia Britannica, 11th ed. (1911), [EB11/R] "Railways," [EB11/B] "Boiler," [EB11/SE] "Steam Engine;" see also "Rolling Mills," "Brake," "Traction," "Coal," "Fuel," etc.
*Ellis, Pictorial Encyclopedia of Railways
*Gordon, Trains: An Illustrated History of Locomotive Development
Armstrong, The Railroad—What It Is, What It Does: The Introduction to Railroading (1978).
Bruce, The Steam Locomotive in America: Its Development in the Twentieth Century (1952)
Clarke, et al., The American Railway: Its Construction, Development, Management and Appliances (1972)(reprint of 1897 edition)
[NOCK/RE] Nock, Encyclopedia of Railroads (1977).
Sinclair, Development of the Locomotive Engine (1970)(reprint of 1907 edition with additional material)
White, American Locomotives, An Engineering History, 1830-1880 (1968).
Connor, Military Railways (1917), available online at http://www.trainweb.org/girr/military_railways/military_railways.html
Krug, "Steam versus Diesel," http://www.railway-technical.com/st-vs-de.html
Ludy, Locomotive Boilers and Engines: A Practical Treatise on Locomotive Boiler and Engine Design, Construction, and Operation (1920), available online at http://www.sdrm.org/faqs/boilers/index.html
Self, "Balanced Locomotives,"
http://www.dself.dsl.pipex.com/MUSEUM/LOCOLOCO/balanced/balanced.htm and "How To Articulate Locomotive," .../articult/articult.htm
Baldwin, "Calculations, Delineations, Classifications,"
http://www.catskillarchive.com/rrextra/blclas.Html
Forney, "The Limitations of Fast Running,"
http://www.catskillarchive.com/rrextra/stspdlo.Html
[WLW] "Whitcomb Locomotive Works,"
http://www.absoluteastronomy.com/encyclopedia/w/wh/whitcomb_locomotive_works.htm
Netherwood, "Operation of Locomotive Type Boilers and Associated Fittings" (2001)
http://www.watercressline.co.uk/tw/pages/mutual.htm
[GW] Great Western Archive,www.greatwestern.org.uk
Robinson and Associates, "Hand Firing of Locomotives,"
http://www.grandscales.com/downloads/Hand%20Firing%20of%20Locos.pdf
Sanderson, "Coal, Combustion and Front End Design,"
http://www.ameng.com.au/article.htm
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Cooper, "Locomotive Addendum," www.1632.org
(*documented source)
IMAGES
Note from Editor:
There are various images, mostly portraits from the time, which illustrate different aspects of the 1632 universe. In the first issue of the Grantville Gazette, I included those with the volume itself. Since that created downloading problems for some people, however, I've separated all the images and they will be maintained and expanded on their own schedule.
If you're interested, you can look at the images and my accompanying commentary at no extra cost. They are set up in the Baen Free Library. You can find them as follows:
1) Go to www.baen.com
2) Select "Free Library" from the blue menu at the top.
3) Once in the Library, select "The Authors" from the yellow menu on the left.
4) Once in "The Authors," select "Eric Flint."
5) Then select "Images from the Grantville Gazette."
SUBMISSIONS TO THE MAGAZINE
If anyone is interested in submitting stories or articles for future issues of the Grantville Gazette, you are welcome to do so. But you must follow a certain procedure:
1) All stories and articles must first be posted in a conference in Baen's Bar set aside for the purpose, called "1632 Slush." Do not send them to me directly, because I won't read them. It's good idea to submit a sketch of your story to the conference first, since people there will likely spot any major problems that you overlooked. That can wind up saving you a lot of wasted work.
You can get to that conference by going to Baen Books' web site www.baen.com. Then select "Baen's Bar." If it's your first visit, you will need to register. (That's quick and easy.) Once you're in the Bar, the three conferences devoted to the 1632 universe are "1632 Slush," "1632 Slush Comments," and "1632 Tech Manual." You should post your sketch, outline or story in "1632 Slush." Any discussion of it should take place in "1632 Slush Comments." The "1632 Tech Manual" is for any general discussion not specifically related to a specific story.
2) Your story/article will then be subjected to discussion and commentary by participants in the 1632 discussion. In essence, it will get chewed on by what amounts to a very large, virtual writers' group.
You do not need to wait until you've finished the story to start posting it in "1632 Slush." In fact, it's a good idea not to wait, because you will often find that problems can be spotted early in the game, before you've put all the work into completing the piece.
3) While this is happening, the assistant editor of the Grantville Gazette, Paula Goodlett, will be keeping an eye on the discussion. She will alert me whenever a story or article seems to be gaining general approval from the participants in the discussion. There's also an editorial board to which Paula and I belong, which does much the same thing. The other members of the board are Karen Bergstralh, Rick Boatright, and Laura Runkle. In addition, authors who publish regularly in the 1632 setting participate on the board as ex officio members. My point is that plenty of people will be looking over the various stories being submitted, so you needn't worry that your story will just get lost in the shuffle.
4) At that point—and only at that point—do I take a look at a story or article.
I insist that people follow this procedure, for two reasons:
First, as I said, I'm very busy and I just don't have time to read everything submitted until I have some reason to think it's gotten past a certain preliminary screening.
Secondly, and even more importantly, the setting and "established canon" in this series is quite extensive by now. If anyone tries to write a story without first taking the time to become familiar with the setting, they will almost invariably write something which—even if it's otherwise well written—I simply can't accept.
In short, the procedure outlined above will save you a lot of wasted time and effort also.
One point in particular: I have gotten extremely hardnosed about the way in which people use American characters in their stories (so-called "up-timers"). That's because I began discovering that my small and realistically portrayed coal mining town of 3500 people was being willy-nilly transformed into a "town" with a population of something like 20,000 people—half of whom were Navy SEALs who just happened to be in town at the Ring of Fire, half of whom were rocket scientists (ibid), half of whom were brain surgeons (ibid), half of whom had a personal library the size of the Library of Congress, half of whom . . .
Not to mention the F-16s which "just happened" to be flying through the area, the Army convoys (ibid), the trains full of vital industrial supplies (ibid), the FBI agents in hot pursuit of master criminals (ibid), the . . .
NOT A CHANCE. If you want to use an up-time character, you must use one of the "authorized" characters. Those are the characters created by Virginia DeMarce using genealogical software and embodied in what is called "the grid."
You can obtain a copy of the grid from the web site which collects and presents the by-now voluminous material concerning the series, www.1632.org. Look on the right for the link to "Virginia's Up-timer Grid." While you're at it, you should also look further down at the links under the title "Authors' Manual."
You will be paid for any story or factual article which is publishe
d. The rates that I can afford for the magazine at the moment fall into the category of "semi-pro." I hope to be able to raise those rates in the future to make them fall clearly within professional rates, but . . . That will obviously depend on whether the magazine starts selling enough copies to generate the needed income. In the meantime, the rates and terms which I can offer are posted below in the standard letter of agreement accepted by all the contributors to this issue.
Standard letter of agreement
Below are the terms for the purchase of a story or factual article (hereafter "the work") to be included in an issue of the online magazine Grantville Gazette, edited by Eric Flint and published by Baen Books.
Payment will be sent upon acceptance of the work at the following rates: