Leaders.....

Apropos the possible length of run for a tank engine, someone please remind us what happened in the Sunny South exchanges between the LNWR and the LBSC.

 

Without resorting to something as banal as "I honestly haven't the foggiest", how about "So that the suggestion for mechanical stoking would come from ASLEF"?

 

Famously the Marsh I3 locos ran Rugby - Brighton on trial, non-stop for 77 miles from Rugby - Willesden Junction and no water pick up for 90 miles from Rugby - East Croydon (or vice versa).

The coal and water consumption figures were, with the comparable LNWR loco:

LBSCR No. 23 (eleven trips): Coal consumption: 27.4 lbs / mile Water consumption: 22.4 gallons / mile
LBSCR No. 26 (one trip): Coal consumption: 28.1 lbs / mile Water consumption: 22.7 gallons / mile
LNWR "Titan" (all trips): Coal consumption: 41.2 lbs / mile Water consumption: 36.6 gallons / mile

Load was typically 7 bogies, about 220 tons.

Apart from showing the abilities of the superheated I3 locos, which is generally how that is pitched, it has always struck me as a skilled bit of firing. Given the stated water consumption, a 90 mile trip only leaves about 100 gallons spare.

Worth pointing out though that the gradient profile - certainly on the LBSCR bit - was much easier than on the "withered arm". The Traffic Manager's specification was for heavier loads on harder gradients than those trials. (Whether that was a realistic specification is a different matter). I would also assume that the LBSCR picked a "crack" crew for the trial, rather than an average crew.

The I3s had 2,100 gallons and only about 100 left over at the end of the trip. FWIW, a BR Standard 4 has 2,000 gallons ...

Tom

 

Flicking through Robertson & he mentioned the Maunsell W himself once or twice so if you're gonna plagiarize, do it from the best! Interesting that Bulleid originally wanted a King Arthur for the testbed. Would that have been better than a H1? The damning thing is the table at the back comparing 36001 to U 31630. 48.6% more water, 68% more coal for example!

 

Why did the Southern never have water troughs? I can understand the Brighton and maybe SECR not having them as they didn't have any particularly long runs, but the LSWR did.

 

I'm not in any position to comment on the gradients of the South Western main line (that's for Tom to do) but you need a reasonable length of level track to have troughs. If you don't have that where it can be used to advantage then there is no point in having them.

 

The LYR and LNWR both managed to get some on their hilly Trans Pennine routes. The LNWR ones were inside Standedge tunnel, which was the only level track on the whole route.

 

Basically because there was nowhere to site them. You need a long distance almost perfectly flat; and there is no point just having one - for example, you would probably have needed two or three between Waterloo and Exeter to make a non-stop run possible and there simply weren't three suitable sites. (If you are unfamiliar with the line, the mainline west of Salisbury was built on a "sawtooth" principle, but it means it is almost universally going either uphill or down, generally at reasonably steep gradients). The Southampton / Bournemouth road is similarly hilly; generally locos would stop at Southampton to take water. The Eastern section is similarly hilly, particularly with big slogs over the North Downs coming out of London.

The upshot was that Southern engines developed with tenders having - for their respective eras - large water capacities while engine changes at Salisbury and again at Exeter became basically essential on West of England expresses. Roughly a maximum 90 - 105 minutes between water stops and / or loco changes became the standard to meet. London to Salisbury / Southampton / Portsmouth / Hastings / Dover or Ramsgate and Salisbury to Exeter are all basically within that length.

Comparing a Merchant Navy and a Duchess is instructive: A Duchess has, I believe, 10 tons of coal but only 4,000 gallons of water. That's enough coal to get to Scotland, provided you repeatedly pick up water. Whereas a Merchant Navy has 5 tons of coal but between 5,000 - 6,000 gallons of water, which will comfortably get you to Salisbury, and back without more coal but after filling with water.

Tom

 

MN's only ran on the line once I think but the WC/BofB's could not make a Bath to Bournemouth round trip without topping up on coal by all accounts

 

The Caledonian and North British also had no water troughs in pre-Grouping days, so were in a similar position to the LSWR. It's 100 miles over hilly terrain from Carlisle to either Glasgow or Edinburgh, so big tenders were a necessity:

https://railway-photography.smugmug.../McKintosh-CR-721-Class-Dunalastair/i-Stcjpnj

 

Mr. Drummond had ambitions of this nature, according to Don Bradley. The one and only (thank goodness!) E14, No. 335, had a scoop fitted to its tender when new, as did the 10 G14 and P14 class, Nos. 448 - 457. The potential sites for troughs were apparently near Fleet (Level from 36M 75ch to 38M 15ch) and Abbey Ford, near Templecombe. I don't know of the location, but the Gradient Manual 1887 shows a level from 109M 55ch to 110M 58ch (crossing the County boundary). Given the imposition of Engine changes at Salisbury after 1906 it's hard to see any need.
Pat

(Edited to correct typo Engine Number. Pat)

 

The troughs on the LYR Calder valley line were at Luddenden foot, near Halifax, and I've read that the track here wasn't quite level, it was a very slight gradient, of 1 in 377. Surely this can't be right? Anyone know?

 

1 in 377 isn't slight! It would certainly be noticeable to the driver of a train. I don't know the minimum gradient down which water would flow over a SMOOTH surface, and how smooth was the inner surface of the troughs might be is speculation.

 

How long were throughs?

 

Usually somewhere between a quarter of a mile and half a mile long

 

If there is a head of just one inch between inlet and outlet then the water will flow, albeit very slowly, until there is no difference in surface level. In theory, you could have water troughs on a falling gradient but it would be flowing water and require constant replacement from a flowing source at the inlet end and an outlet at the downstream end. No different from a small stream, really. I'm not saying that was the case at Luddendenfoot, though.

 

Why didn't the leader concept have oil firing, or liquified coal firing, that would have at least made the fireman's job easier as the fireman's cab would have not been subjected to the heat of the original design, the firebox could have been insulated and cab had cooling ducts built into it, to make the fireman's job cooler. but I guess the writing was already on the wall for steam at this point and I would have thought the Southern diesels would have been a far better option for the north Devon lines, a smaller BO BO version with a lighter axle weight .

 

The plan was, I understand, to use oil firing but oil imports were very much reduced just after WWII. Britain was skint with little in the bank; the emphasis was on exporting rather than importing. Basically, it was home produced coal or nothing. The big plan to convert many engines to oil firing, and for which the oil storage tanks were built t some sheds, fell at the same hurdle.

 

Yes, an oil storage plant was built at Rose Grove but the scheme was abandoned before a single drop of oil was ever delivered to the shed and it stood, unused, until the shed closed

 

I don't think gradient is the reason for lack of Southern troughs Tom - it's population density. In the north, faster trains could run up to 100 miles or more between major stops - something that never happened in the South because station stops even for expresses were typically closer together. On the south western main lines all express trains stopped at Southampton or Salisbury (70 miles from London) so water replenishment was made then. As you say, a Southern pacific tender could handle the requirement without the need for troughs. Had they been required the stretch between Farnborough and Basingstoke offered plenty of scope for them but no trains ran the distances between stops that would have required them.