I'm still learning the definitions of steam locos and what makes them work and here's a question I need help on.
I am preferable to the N&W railway and I know they both had a 2-8-8-2 and a 2-6-6-4 locomotive in use (or so I think) and I have heard them referred to as a Mallet. Is both of them Mallet locos or is only one of them a Mallet?
Thanks
Daniel
Modeling the N&W freelanced at the height of their steam era in HO.
Daniel G.
In North American terminology an "articulated" is a locomotive with one boiler, two engines, both engines under the boiler the engines mounted on separate frames, one frame affixed rigidly to the boiler and the other engine hinged to the first. Each engine has a pair of cylinders of identical size. The Mallet is a subset of the articulated locomotive that differs significantly by having compound cylinders -- typically the rear cylinder pair are high pressure and the front cylinder pair is low pressure. The steam is used twice, first in the rear engine and second in the front engine, and then exhausted. The "simple" articulated, by comparison, has four identical high-pressure cylinders.
Mallets appeared when compounding was all the rage, in the first decade of the 1900s. Later as labor costs became more expensive compared to fuel, the excess maintenance requirements and lower availability of the Mallet caused compounding to fall out of favor. Many Mallets were "simpled" i.e., the front cylinders were converted to high-pressure identical with the rear -- but some railroads found the Mallet more cost-effective right to the end of steam for low-speed drag-freight service. Mallets were not appropriate for medium-speed and high-speed manifest service as the low-pressure engine had too much steel moving back and forth to operate at high speeds without very high maintenance costs and failure rates, so roads that wanted to use articulateds for medium- and high-speed traffic purchased simple articulateds, or in some cases simpled Mallets (or even converted articulateds into ordinary rigid-frame locomotives such as 2-8-4s.)
In common, everyday railroad lingo, it was commonplace for railroaders to refer to all articulated locomotives as Mallets even if they were simple. Technically a Mallet has to be a compound, however. Often the non-Mallet articulated is called a "simple articulated."
RWM
Railway Man gives a very detailed and accurate description of the differences between simple and compound articulation. However, the term "Mallet" is much more simple. Anitole Mallet designed the articulated engine in order to get bigger engines around tight curves. It's as simple as that. The fact that the early ones in the US were compound is because, like Railway Man say's, "It was all the rage". The name "Mallet" was given to the engines because of the articulation design, not the fact that they happened to be compound at the time.
Dick
Texas Chief
You inspired me to reach for a book on the shelf I've never even cracked open -- the 1970 Kalmbach reprint of Lionel Wiener's "Articulated Locomotives," originally published 1930.
The Kalmbach "Guide to North American Steam Locomotives" agrees with the premise that Anatole Mallet's goal was to design a flexible locomotive first, and in the process he applied compounding to it because that was the fashion of the time, in the same manner that a locomotive of 1870 had a cab, a pilot, and other standard details. And at first Weiner's book seems to support that premise. But reading further, it says:
"Mallet's semi-articulated locomotive was, in a sense, a side issue in the general application of compound working to the locomotive, which he was the first to bring into satisfactory practical use [patented 1874, first applied 1877]. As he experienced great difficulty in introducing compounding for ordinary locomotives, he proposed, in 1877, to apply it to articulated locomotives on the Meyer and Fairlie systems; his first attempts led, however, to inconclusive results. Finally on June 18, 1884, Mallet took out the French patent No, 162,876 for the system of articulated locomotives which has made his name famous throughout the world."
Just to make things more interesting, the book on the next page states, "On the other hand, simple Mallets have been tried for many years, but with poor success."
It's not unreasonable to interpret Wiener either way -- that Mallet's first goal was to make a compound locomotive and making it semi-articulated aided in reaching that goal, or that Mallet's first goal was to make an articulated locomotive and it happened to be compound by coincidence. I think I would want to poke around further in the library and read more about compounding.
dale8chevyss wrote:Thanks for helping me understand the terminology of locomotion. I'm trying, and slowly but surely understanding how things work and what they are called.
May I recommend the book...
The Locomotive Up To Date By Chas. McShaneCopyright 1899 by Chas. McShaneRevised by Chas. L. McShaneCopyright 1920 by Chas. McShaneGRIFFIN & WINTERSNew York Life Building, Chicago, Ill. 1923
It must be noted that it is a book from 1920, changes and improvements continued in the industry, some of which may contradict or supplant the information presented. An interesting note; in an earlier (1909) edition of the book, Walschaerts' Valve Gear is mentioned as being extensively used on the Belgian State Railways "but probably will not receive much attention from locomotive builders beyond that kingdom"... a scant half page. Whereas, the revised (1920) edition devotes nearly 60 pages to the design; it became one of the most popular designs, not just in Belgium, but all over the world.
The 1920 edition is available free on one of the web sites that were listed in another of this forum's threads:
http://www.trains.com/trccs/forums/1292037/ShowPost.aspx
It is unfortunate that the downloaded version is just a photographic reprint of the book and is not in a text searchable format... never-the-less, it is a great read and even if you absorb only a few percent of it you will be a long way toward understanding steam locomotives. If you absorb most of it and want more, then I would recommend:
La Locomotive A VapourBy Andre ChapelonFrench edition copyright 1952 - the Estate of Andre ChapelonSecond French Edition, English TranslationGeorge W. Carpenter C.Eng., M.I.Mech.E.Copyright 2000 George W. Carpenter and contributorsISBN 0 9536523 0 0Published in Great Britain byCamden Miniature Steam ServiceBarrow Farm, Rode, Nr. Bath, Somerset, BA3 6PS
but this is really for the really deep thinker!
SEMPER VAPORO!
Semper Vaporo
Pkgs.
In as much as you have an interest in the Norfolk and Western, be advised that the general statement excluding Mallets from even medium speed service was not the norm on the N&W, as they routinely operated the Y's in the 50 MPH range. This is NOT drag service. The A's did not operate on the Shannandoah Division, which made the Y's the primary freight power for almost all assignments. Until very late steam N&W restricted their Mountains to passenger service. I saw a lot of those puppies at speed, as well as more than a few empty hopper unit trains Westbound at a good clip behind Ys.
I grew up with the definition that a Mallet was an articulated locomotive, whether compound or simple, but I have seen the argument putting forth that a Mallet was a compound articulated grow over the last 25 years or so. I don't know why someone thinks this is a huge deal.
N&W could have ofeten been addressed in a lot of articles, if they had merely added "except for the N&W". They were indeed 'Precision Transportation'.
The A's did not operate on the Shannandoah Division
For the most part a true statement. However, the A's were rated for tonnage between Roanoke and Hagerstown. I have one eyewitness account of an A in Shenandoah. Steam engineers said that an A would occasionally make a trip up the Valley, but it was rare and had to be done under the Supt. name because the A's did not have cab signals.
One engineer remarked that he didn't like to run a Y6 over 63 mph as they got pretty shakey after that!
.
BigJim,
Was the Shenandoah line busier during the 1950s than it is now ?
I would say that it probably was. We were busier in the '70s than we are now. The busiest would probably have been during the WWII years. There were a lot of sidings back then that were abandoned long before I started.
The problem with compounding in Mallet's time is that the steam was generated at too low boiler pressure, too high back pressure and too low temperature to make compounding useful. The N&W Y-6 used 300 psi superheated steam and the LP exhaust was designed to minimize back pressure (i.e. compounding done right).
Compounding was very common in stationary and marine applications as use of a condenser dropped the back pressure to a fraction of atmospheric pressure.
Just an etiquete note for Newbies;
When in polite company, please remember to pronouce "Mallet" correctly.
Its pronounced ma-LAY , not MAL-et, like the hammer. Mallet was French, so the pronouniation is different than in English. I say this as its a very common mistake made by those unfamiliar with the inventors origins. Most books just say "mallet" with no reference to its correct pronounciation, they just "assume" the reader will be familiar with the word. Correctly calling the engines by the right pronounciation helps one look less like a newbie pudknocker when discussing trains in pleasant conversation.
Have fun with your trains
There was this Saturday Night Live sketch where guest-host (the whole point of being the guest host is to be the butt of all the jokes) Jimmy Smits, an American actor of Hispanic heritage, wanted to order some Mexican food, and everyone took turns correcting his Americanized speech by using overwrought pronunciations of Spanish-language words.
mal-LAY is probably close to correct French-Swiss, but are we going to drive people out of railfan-dom by saying MAL-ee, which is like the white-shirt and slicked-hair sales people calling that that car with the name Camry a "CAAM-ree" -- seriously, no one calls that popular-selling auto that many of you out there drive a cahm-RAY.
If you showed up to train club and said the hard "t", people will turn to see if you are wearing your hair in a mullet and look at your hands if you earn your occupation swinging a mallet, but if we get newbies saying the full-blown "mal-LAY", that might get some stares too.
If GM "killed the electric car", what am I doing standing next to an EV-1, a half a block from the WSOR tracks?
I seem to have missed the audio option for this forum. Can someone tell me where to find it?
Enjoy
Paul
I've always heard that in American English, the inventor's name was pronounced something like MAL'-lay and the locomotive was pronounced MAL'-lee. If I recall my schoolyard french correctly, Mallet is pronounced Mallai, with no accented syllable, the first "a" similar to the American short "a", the "L" pronounced with the tongue behind the UPPER teeth and ai pronounced something like a long "a" but cut off about halfway through. I just remember the sound; I lost the ability to actually duplicate it a long time ago.
I think what VSmith was driving at was that many people seeing the name say "mallet" like the thing you use to hit a croquet ball with, with the first syllable rhyming with "pal" as in your friend, and the last syllable sounding like the word "let".
The correct pronounciation would be more like "Mall-LAY"..."Mall" like shopping mall, "lay" like lay down.
In America we generally say "Mal-lee" - "Mal" like 'pal' and "lee" like the name Lee.
Just to stir the pot a little more, back to the original question, a Mallet is generally defined as a steam engine having two sets of drivers, where the first set of drivers are articulated so they can turn separately from the rest of the engine, and that uses steam in a compound set-up with high and low pressure cylinders. Articulated engines that use high pressure steam directly to all four cylinders were often called "simplified" or "simplex" articulateds.
BTW a little off subject but it's become popular in science programs on TV and such to pronounce "Halley" from Edmund Halley of Halley's Comet fame as "Hal-lee" with the "Hal" sounding like the name Hal. This is wrong; back in 1986 the BBC visited Edmund Halley's descendents who still live in the same country estate in England, and the family explained it was "Hall-lee" with the "Hall" pronounced just like the word hall or as in "hallway".
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