London & North Western 4-4-0 Locomotives in Great_Britain

Class Alfred/Benbow (Locobase 2186)

Four-cylinder compounds that were first rebuilt as Benbows using a new design of reversing gear, then as 2-cylinder simples known as the Renown class. In using a valve gear that allowed different cutoffs for the high- and low-pressure cylinders, this design showed better than the preceding Jubilees. Charles Rous-Marten, in his "British Locomotives in 1905," 1906 Bulletin of the International Railway Congress (Volume XI), pp. 556, says that the duplex valve-gear was devised by George Whale, and was a mechanixm that "...renders them really useful locomotives."

Note: Tuplin (1963) gives a nominal tractive effort of 20,000 lb, commenting that it is "that of the simple engine produced by removing the high-pressure cylinders." The number given in the specifications is based on a 1924 ARA formula.

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Class Black Prince (Locobase 1470)

Reder (1974) p 201-202. Ahrons (1927).

Webb compound design that was an departure from his earlier practice. Instead of a 3-cylinder setup, Webb used 4 cylinders arrayed in a single plane and driving the leading coupled axle; the HP cylinders lay outside, the LP inside the frame. The ratio between HP and LP cylinders is badly out of balance, however, with the LP cylinders too small to take full advantage of the compounding principle.

Regardless of this imbalance, however, Webb felt able to proceed with a production batch of 38 more dubbed the Jubilee class; see Locobase 2185.

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Class George the Fifth (Locobase 2193)

Data from "New Express Locomotives, L&NWR", The Locomotive, Volume 16 (15 October 1910), p, 213; and "The 'Coronation' Engine, L&NWR", Locomotive, Volume 17 (15 July 1911), p. 159.

John Charles Bowen-Cooke's only 4-4-0s on the London & North Western. Engine #1595 generated 910 drawbar hp while averaging 61.9 mph for 2 hr 18 min and pulling a 410-ton load between Willesden and Whitmore in January 1912. This performance ranked quite high in comparison to other pre-World War I British engines.

Hollingsworth (1982) confirms the impression of power: "To the solid simplicity [of the Precursors] were added [8"/203 mm] piston valves and superheaters with results that today are hard to believe." OS Nock (RWC IV, pl 125) acknowledges the "almost phenomenal output of power ...in their prime, during the years 1910-1916, they were incomparable."

Nock is forced to add, however, "It was unfortunate that these otherwise brilliantly successful engines were built on the same chassis as the less powerful Precursors and the great power they developed caused troubles with the frames. With increasing age they became heavy on maintenance costs and had to be relegated to lighter duties." After absorption into the LMS stud, less well acquainted engine drivers thought less of the Georges and retirement began in 1935.

Nock's illustration shows a straight-boilered design and Hollingsworth (Steam Passenger Locomotives, 1982) asks the reader to note "the round top outer firebox wrapper instead of the more complex Belpaire pattern ..." , but an accompanying photograph and another available at [] clearly show a Belpaire boiler. According to Steam Index's review of L&NW designs, the Belpaire firebox is a result of a mid-1920s rebuilding

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Class Iron Duke (Locobase 2266)

Data from Edward Cecil Poultney, British Express Locomotive Development (London: George Allen and Unwin, 1952), pp. 24-28.

This single locomotive was a simpled, four-cylinder version of the Webb compound. Poultney noted that this engine, like all of Webb's designs, had "ample axle journal bearings"; the cranks for adjacent cylinders were set on opposite centers. The outer valves were operated by horizontal levers actuated by the extended spindles of the inner valves. Poultney could not be certain that these were in fact piston valves, but thought it likely. 1501 also tested a double-chimney (stack) layout in which one set of cylinders exhausted into a shorter blastpipe above the other, which took the exhaust of the other pair. The physical mark of this innovation was a long stack top that resembled the thin Geisl ejectors adopted almost 50 years later.

Iron Duke kept its name and its four-cylinder, simple-expansion system for only a short time. It was converted in the same year to the 4-cylinder compound layout first tested in 1502 Black Prince (Locobase 1470).

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Class Jubilee (Locobase 2185)

Data from the table presented on pages 366, 368 of the Groupe VI. - GTnie civil. - Moyens de transport. DeuxiFme partie. Classes 32 (Tome I), part of the series of Rapports du Jury Internationale of the Exposition Unverselle Internationale de 1900 Paris Exposition, hosted on the website of Le Conservatoire numTrique des Arts & MTtiers ([], Accessed 21 August 2005).

Four-cylinder compounds that were soon rebuilt as two-cylinder simples known as the Renown class. The first was named Iron Duke after the four-cylinder simple trial horse of that name (Locobase 2266) was renamed Jubilee. The Black Prince prototype is described in Locobase 1470.

Glover (1967) comments that they had an unsatisfactory ratio between the cylinders: "They were, moreover, hopelessly underboilered and their performance was mediocre."

A check of the ratios confirms Glover's opinion in every respect: A functional LP/HP ratio might be 2.4; the Jubilees (also known as the Diamond Jubilees) sported 1.87, which implies a waste of steam. And while most 4-cylinder compounds showed a value over 400 when dividing the heating surface by the HP cylinder volume, the Jubilees display a modest 287. In other words, The boiler was small to begin with and the HP cylinders gorged themselves on steam they couldn't efficiently pass along to the LP cylinders.

Other features included long connecting (main) rods of 10 ft 7 inches.

Such a malproportioned system should have proved a flat failure in service, but Charles Rous-Marten (10 Jan 1903 Locomotive Magazine (Vol VIII, #85), p 23) reported that during the 1902 season "...excellent work was done by the 'Jubilee' and 'Alfred the Great' types, which have on many occasions taken loads of from 320 to 370 tons behind the tender, over the 158 miles between London and Crewe without a stop, at an over all speed of 54 miles an hour." That was creditable performance indeed, its most striking feature being the low coal and water consumption.

Marten acknowledged that the trains had help: "It should be mentioned that almost invariably recourse was had to the services of a pilot + usually a four-coupled 'Precedent,' or one of the three-cylinder compounds. This was, of course, the result of the order issued in October, i go i , that for the future on the L. & N. W., the equivalent of 17 ordinary six-wheeled coaches should be regarded as sufficient load for one engine.

Note: Tuplin (1963) gives a nominal tractive effort of 20,000 lb, commenting that it is "that of the simple engine produced by removing the high-pressure cylinders." The number given in the specifications is based on a 1924 ARA formula.

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Class Precursor (Locobase 2191)

Data from Edward Cecil Poultney, British Express Locomotive Development (London: George Allen and Unwin, 1952), p. 58-59, supplemented by A T Taylor, Modern British Locomotives (London: E & FN Spon, Ltd, 1907), p. 15.

The first of George Whale's designs, these engines operated until the late 1940s. Glover (1967) describes their performance as "phenomenal," and attributes it to a large firebox heating surface and the Joy valve gear. Poultney noted the large steam ports (2" x 15") hat constituted 10 1/2% of the piston area, but described the limited size of the grate as "...a rather weak feature in the design." In summary, however, "The design ...was characterized by its striking simplicity and an exceedingly neat appearance."

The Railway Magazine's celebration of "The Diamond Jubilee of the London & Northe-Western Railway - The Locomotives" of August 1906 (p. 124) commented that early results showed that the Precursor were "...an unqualified success; single-handed they are hauling the heaviest express trains on the North-Western Railway, and, from every point of view, have attained the objects for which they were designed."

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Class Renown (Locobase 2188)

Rebuilds of 70 Jubilee and Alfred/Benbow four-cylinder compounds. As simple-expansion engines, these served until 1935.