Is this a Mallet ?

Would anyone know which railroad it would have been on ?

Yes this is a true Mallet (huge front cylinders and smaller rear ones - indicating that this is a compound engine), and it looks very much like a D&RGW L-95 or L-96. I would have to look into my library for the engine’s history, but since this would take about a week I think others will be faster than me.

Dale: I would also go with the Rio Grande L-96 class 2-8-8-2s built by Alco-Schenectady in 1913. There were 16 built #1060-1075 and then renumbered to #3400-3415. They left the roster between 1944-1952. Data from Locomotives of the Rio Grande by the Colorado Railroad Museum.

Ed

Dale,

You can also find some photos of these units on page 294 of Beebe & Clegg’s book “Rio Grande, Mainline of the Rockies”

Dan

Good work guys, thank you !

Could the location be at the east portal of the Moffat?

Perhaps MWH or MC might know.

http://www.drgw.net/info/index.php?n=Main.L-96

I have found another picture for comparison.
http://images.google.com/imgres?imgurl=http://www.somewherewest.com/RioGrande/DRGW5317Moffat.jpg&imgrefurl=http://www.somewherewest.com/RioGrande/RioGrande.html&h=600&w=800&sz=106&hl=en&start=19&sig2=5Q9_NVZii0Zm9R4xOovmRA&tbnid=Ho8rIfSx-Zs5hM:&tbnh=107&tbnw=143&ei=BhweR-WGLpKKiQHxn7DhBg&prev=/images%3Fq%3Dmoffat%2Btunnel%26gbv%3D2%26svnum%3D10%26hl%3Den%26sa%3DG

And here is the pic from that website.

I see the “true Mallet” argument is alive and well. Mallet’s chief contribution is the under-boiler articulation; compounding preceded him, and most likely he resorted to compounding due to the boiler sizes available in his era, which would not have been conducive to simple-expansion engines of his articulated type. Mallet compounds were considered comparative failures due to the steam pressure lost when the front engine was “out of phase” with the rear engine due to driver slippage or whatnot, resulting in loss of power; also, the extra weight due to the size of the low-pressure cylinders and the associated connecting gear exerted an extra-hard pounding on the tracks.

Compounding works best on non-articulated four-cylinders where the outer cylinders are simple-expansion and the inner cylinders are low-pressure compound expansion (or is it vice-versa; can’t remember now); the advantages related to driving wheel balance make disc (boxpok) drivers seem brutish by comparison (although the mechanical complexity certainy would have been too much for US railroads to deal with).

Could it be on the Denver and Salt Lake RR Just asking

JT22CW

You may want to tell the now-departed N&W people about their comparative failures regarding the Y5-Y6b classes. All were compound 4-cylinder articulated locos. They met the requirements of N&W’s bottom line and stockholder requirements (read dividends and low operating costs). The out-of-phase argument is more theoretical than pragmatic.

The driver style mentioned is interesting. Why is boxpok better than spoked? N&W used spoked and ignored boxpox drivers with considerable success. Other carriers used boxpox to the exclusion of spoked on their more modern locos. Still other railroads used a mix of spoked and boxpox on the same locomotive. The boxpok had some advantage re: counterbalancing, but I don’t recall what it was.

No argument regarding the French 4-cylinder compounds. Their performance and power output fro a relatively compact locomotive is amazing, particularly in contrast to the US “make it big” idea.

The N&W was highly peculiar when it came to their tolerance for steam loco maintenance; even unusual. Their definition of “success” relative to other roads may not be comparable. Engine units on compound Mallets going out of phase was not merely theoretical; it did happen, and it’s not a stretch to theorize that other railroads that used the N&W’s USRA-derived designs (PRR, UP, VGN) found themselves averse to the mechanical complexity required in the Y-class, otherwise machines like the SP’s cab-forwards (their first versions being compound) and UP’s Alco-commissioned articulated locos would have adopted the compounding concept wholeheartedly.

Same concept applied to N&W related to boxpok driving wheels. Ever seen the size of the counterweights on 611?

The only thing peculiar was that the other RR’s couldn’t figure out how to make the compound 2-8-8-2 become the top-notch locomotive as the N&W did.

N&W had more success with compound 2-8-8-2’s primarily because management realized that they were low-speed designs best suited for moving lots of mineral freight at less than manifest speeds. I don’t think that a Y-6 would work too well in manifest service on ATSF, NKP or any other roads that were oriented to fast freight.

D&RGW took over D&SL in 1947 (owned a majority of its stock since 1932)

Dale: not seeing enough to tell where it is.

I think Bob found the spot. The ridgeline in that 5317 photo matches the mallet picture, as far as I can tell. I think the notch above the second diesel is the same as the notch above the second boxcar.

JT22CW, are you English, French, or what? I agree that Mallet’s primary design feature was the articulation rather than the compounding, but recent popular opinion seems determined to have both to call it a mallet; wrong or not.

The N&W did not copy from USRA, originally the USRA copied from N&W. The other railroads mentioned did not have a problem with the ex-N&W locos, except they were too slow for the western roads’ favored methods of operation. Virginian obviously had no problem with the design, or they would not have purchased third hand 30 year old locomotives. N&W and Virginian did not need any advice on how to haul coal and make more money doing it than anyone else, even from 60 years in the future. It is significant to me that some of the last new steam locomotives N&W built were Y6b compound locos. They certainly knew how (witness the Class As) and had the wherewithal to build simple articulated locos had they desired, they even had drawings for a possible Y-7, but the economics favored the compound.

Relative to the phasing of the high and low pressure engines, it was critical to have sufficient volume within the low pressure piping and acoutrements ahead of the low pressure cylinders to facillitate compound operation. If you look at a dynamometer car printout it is obvious N&W did not have a problem.

Virginian had a long experience with their 800’s, which were compound and had tremendous tractive effort, and it did not dissuade them from buying what became their USE class compounds. While the 800’s were quite slow with a load, N&W routinely ran their Y classes up to 50 MPH.

N&W realized more efficient maintenance would lead to better operations decades before the “Japanese manufacturing methods” permeated the American industrial base. If you call that peculiar I can live with it.

What is/are boxpok drivers intended to

There’s a clue right in my handle. Look up which countries bought EMD’s JT22CW, and it’s the one English-speaking country physically closest to the USA in Europe (another clue; it’s not part of the mainland).

IIRC, the Y2 was jointly developed by N&W and Baldwin (whereas the Y1 was all-Baldwin). The Y2 is the design that the USRA developed into what became the Y3.

N&W and VGN were a lot closer than their “rivalry” made it appear; certainly, the USRA operated them as one railroad. They would have merged a lot sooner than 1960 had the ICC not turned them down several times.

Remember, I’m not arguing that the Ys were unsuited to the job they did. I am stating that their methods were peculiar to the USA and more labor-intensive than other railroads. Clearly, it didn’t hurt their bottom line significantly; or perhaps there was a different corporate culture at work there.

Driving wheel slippage would have taken its toll, though. Given the sheer bulk of the Ys, and the low-speed nature of its primary operations, certai

“these are based on highly-stressful worker-exploitative environments”

Right on !! Oh man is it good to find one more individual who recognizes the Oriental “mystique” for exactly what it is. I was being a bit facetious about the methods, but I do believe N&W, almost uniquely, recognized the whole system of motive power, operations costs, maintenance, and fuel costs as all playing a part of the sum, and their lubritoriums et all were a rather cheap pallitive to the needs of steam. As the costs of oil and coal have gone their relative ways, it is worth noting they definitely had a point.

Anatole Mallet’s interest was in compounding, and his first such locomotives were two-cylinder non-articulated locos in 1877 - AIUI the first successful compound locos.

He subsequently developed the semi-articulated design (for which he is known) as a solution (AIUI) to the problem of how to arrange four cylinders on a loco - his patent for it was specifically for a form of compund.