London & North Western 2-2-2 Locomotives in Great_Britain

Class 373 (Locobase 2207)

Data from Ahrons (1927) and David Kinnear Clark, The Exhibited Machinery of 1862: A Cyclopaedia of the Machinery Represented ... (London: Day & Son, 1864), p. 10.

These engines had large grates -- and 242 sq ft of firebox heating surface which Glover (1967) describes as "phenomenal". He also notes that McConnell was unperturbed by the unusually high-pitched boilers with their centers 7' 5 1/2" above the rails. Another unusual, but forward-looking feature was the provision of combustion chamber to complete burning before the gases entered the shorter firetubes. Although McConnell liked to run his engines at 150 psi, these later Bloomers ran most of their career at 120 psi (8.3 bar) , then 140 psi (9.66 bar).

Ahrons noted in his description that, contrary to "expert" opinion, engine drivers themselves actually preferred these engines to the Crewe-built examples.

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Class Bloomer (Locobase 661)

Ahrons (1927) for data. See also Clement Edwin Stretton, The Locomotive Engine and its Development (London: Crosby, Lockwood and Son, 1896), pp. 111-112.

Called "Bloomers" because of their cutaway splashers, these engines, designed by James E McConnell, were among the first to have a boiler set high. In this case, it was to clear the crank axle of the 7-foot drivers. To accommodate the firebox he desired, he stretched the wheelbase. Valve motion and cylinders were inside.

The result was a very successful express passenger design that was built in large numbers. Sharp, Stewart delivered the first 25 in 1851-1861. They were later run at 120 psi, which reduced their nominal tractive effort to 6,840 lb. Ahrons noted that these were the preeminent London & North Western express engines until the 1880s, "and in their day they were the best express engines on the line."

Three engines had 90-in drivers.

Locobase 3302 discusses McConnell's rejecton of the "low boiler" theory of locomotive design. Slightly later in his 1896 review of locomotive design, Stretton revisits the controversy with a firm endorsement of McConnell's combination of the solution to the problem of large wheels, inside cylinders, high steam pressure and high boilers."

See 2207 for the last 10 Bloomers, which were considerably bigger.

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Class Cornwall - 1858 rebuild (Locobase 14409)

Data from E C Poultney, "Seventy-Three-Year-Old Locomotive in Service in England," Railway Mechanical Engineer (November 1920), p. 691.

Francis Trevithick's original Cornwall sought to match the high speeds reached on the broad-gauge (7 ft 0 1/2") Great Western while keeping the center of gravity as low as possible. All of the boiler tubes were placed under the driving axle while the leading axle was fed through a transverse tube that penetrated the tube bundle forward. Poultney reported that while several accounts used a diagram that showed eight wheels (two fixed carrying axles ahead of the driver, one behind), "in reality the engine always ran on six wheels."

In 1858, Ramsbottom made over the Cornwall completely, adopting a design that would appear within the year as the L&NWR's "Problem" class (see Locobase 662). The principal differences apart from the enormous driver diameter, which was retained, were a slight decrease in tube heating surface area and a minor reduction in cylinder diameter.

Trailing light train loads, Cornwall easily topped 70 mph (113 km/h) and averaged 50 mph (81 km/h) between Crewe and Chester in 1884. From its rebuild to 1905, when it was retired from regular service, the Cornwall was claimed to have traveled 928,838 miles (1,495,429 km), much of it in later years between Liverpool and Manchester pulling expresses on a 45-minute schedule.

Although retired and intended for preservation, the Cornwall was semi-permanently coupled to a six-wheel coach that had a coal bunker and water tank forward, accommodations for the Chief Mechanical Engineer and staff, and an open covered platform at the rear. Cornwall was photographed in 1920 coupled as helper to the pilot of a new Claughton-class express engine.

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Class Crewe (Locobase 648)

Data from Ahrons (1927). See also "Alexander Allan" on the estimable Steamindex website at [], last accessed 12 December 2020.

Alexander Allan of the London and North Western's Crewe works has in the past been given the credit for seeing the benefit of eliminating the crank axle (greater strength and less binding on tight curves). Forrester's "Boxer" engines showed the need to absorb the piston force in the main engine frame.

It seems more likely that it was a Crewe Works design for which Allan should get only minor credit. Steamindex's review of the evidence strongly supports this assertion, which is likely the source for Locobase's original comment. The design used an external frame that carried the leading axle and cocked the cylinders at a slight angle to clear it.

The resulting design was much smoother than Forrester's and became a standard for the L&NWR. 158 2-2-2 passenger and 238 2-4-0 freight engines (Locobase 668) were built from 1845 to 1858. All but eight were named.

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Class Crewe (Locobase 8403)

Data from Samuel Rendell (M. I Mech.E), "The Steam Locomotive: Fifty Years Ago and Now", read Saturday, 13 January 1906 and published in the Transactions of the Manchester Association of Engineers 1906 (January to March).

These single-wheelers were designed by Francis Trevithick.

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Class Lady of the Lake-rebuilt (Locobase 20138)

Data from "Mr J[ohn] Ramsbottom's 'Lady of the Lake' Class--L&NWR", Locomotives and Railways, Volume 1, No 10 (October 1900), pp. 142-145.

Locobase 662 describes the classic express single locomotives of the "Problem" (aka Lady of the Lake) type, which began service on the L&NWR in 1859. They were refitted in the 1870s, but in the late 1890s, James Webb undertook a much more extensive rebuild.

Except for the cylinder volume and tube heating surface area, all of the dimensions grew. Firebox area grew slightly and grate area a bit more. Three-inch (76.2 mm) tires increased driver diameter, the effect of which on tractive effort was offset by a 30 psi (2.07 bar) rise in boiler pressure. All the weights and the engine's axle loading rose as did the boiler's diameter. Frames received cross-stays and some of the class even sported piston valves.

Although these were small singles compared to those on other British railways, their proportions suited them well for fast work on light trains. They also served capably as "pilot" (i.e., helper) locomotives on expresses, handling 80 mph (129 kph) running.

Even so, train weight growth continued unabated and the updated "Ladies" could not compete. The L&NWR withdrew the last of the class in 1907.

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Class Problem/Lady of the Lake (Locobase 662)

Data from George Findlay, "The Working of Railways", Institution of Civil Engineers, Session 1874-75-Part III, Section I-Minutes of Proceedings (23 February 1875), pp. 1-18, particularly the table on p. 5. See also Samuel Rendell (M. I Mech.E), "The Steam Locomotive: Fifty Years Ago and Now", read Saturday, 13 January 1906 and published in the Transactions of the Manchester Association of Engineers 1906 (January to March); and "Mr J[ames] Ramsbottom's 'Lady of the Lake' Class--L&NWR", Locomotives and Railways, Volume 1, No 10 (October 1900), pp. 142-145.

John Ramsbottom, locomotive superintendent of the London and North Western, was required to solve the "problem" of developing an effective express engine for relatively little cost. He simplified the Alexander Allan design by eliminating the outside frame and having only a single leading axle. The horizontal outside cylinders were mounted over the leading axle and drove enormous single drivers.

A characteristic of English express engines of this time were the slotted splashers, those on the "Problems" having a slight hump in the belt line over the wheel hub. The L&R author summarized Ramsbottom's design in 1901 as "singularly compact and graceful". Adding that his ability as 'an artist in metal work' outshone even that of the Great Northern's Patrick Stirling, the appraiser added that his aim was "always to conceal the power of his engine under an almost airy-looking exterior."

These engines served for almost 50 years. 60 were built from 1859-1865, all but the first ten being completed with Giffard feedwater injectors instead of hand pumps. (The first ten were presumably refitted with these soon afterward.) Surviving engines were modestly rebuilt in the 1890s, increasing boiler pressure to 150 psi (10.34 bar) and perhaps increasing driver diameter to 93 in, (2,362 mm) although that is not clear from Locobase's sources. At high speeds, these engines pivoted around a vertical axis, but were otherwise very satisfactory.

A contemporary account -- Scientific American Supplement, No. 458, October 11, 1884, reproduced by Project Gutenberg at ftp://sailor.gutenberg.lib.md.us/gutenberg/1/1/6/4/11647/11647-8.txt, accessed 25 January 2007 -- noted that "These engines burn about 27 lb. of coal per mile with trains of the gross weight of 117 tons, which is not at all an economical duty. "

The Lady of the Lake was displayed in 1862 and gave her name to the class in some publications. The Watt ran 130 miles nonstop at 54 1/2 mph average speed in 1862 to convey a conciliatory American answer to the British government following the Trent Affair; this marked one of the first uses of Ramsbottom's water troughs. Among other engine names were: Atalanta, Edith, Erebus, Fortuna, Harlequin, Pandora, Princess Royal, Problem, Soult, And Tornado.

In the late 1890s, James Webb added some years to the design's career through a substantial rebuild; see Locobase 20137.

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Class Small Bloomers (Locobase 3493)

Data from Ahrons (1927), p. 94.

Derived from McConnell's Bloomers (see 661 & 2207), these engines worked in the southern division pulling secondary fast trains. The low factor of adhesion implies a slipperiness borne out by Ahrons's comment that they were not quite as successful as the larger Bloomers because they had so little weight on the drivers.

Vulcan Foundry and Hawthorns together supplied 11 engines, while Wolverton produced 25.

NB: Tube length is an estimate based on the calculation of tube surface area by subtracting reported firebox heating surface from reported total evaporative heating surface

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Class unknown (Locobase 3494)

Data from Ahrons (1927).

Designed to pull express trains between London and Birmingham (112 miles) in a level 2 hours, these engines "were amongst the most remarkable of their day." Built in equal numbers by EB Wilson & Co and W Fairbairn and Sons, these engines suffered, in Ahrons' opinion, from McConnell's uncharacteristic unwillingness to put the center of the boiler more than 6' 10" above rail level. "[t]here are few more striking examples of the effects on the whole design of a too-rigid limitation of a single dimension."

George Augustus Nokes Evolution of the Steam Locomotive (London: The Railway Publishing Company, 1899), pp 165-166, gives a detailed description of the unusual firebox of this class: "The whole length of the fire-box was 10ft. 6in.; depth at front-plate 6ft. 5in., at door-plate 6ft. 10in.; length on fire-bars 5ft. 10Jin., thus leaving 4ft. 7 in for the portion over the axle and the combustion chamber. At its narrow part (directly at the top of the recess above the driving axle) the fire-box was only 2ft. 3in. in height; height at tube-plate 3ft. (beyond the cut away portion); width at tube-plate 3ft. 9in.. McConnell's combustion chamber was a continuation of the fire-box."