Between 1903 and 1905 the Great Central Railway procured a total of 40 class 9K tank locomotives for the suburban routes of London, which were based on the 2-4-2T class 9G tank locomotives and were designed by John G. Robinson. They were created by enlarging the boiler on the 9G and accommodating the extra weight and length by replacing the leadingaq axle with a bogie. They were stationed at London's Marylebone railway station and were distinguished by the fact that they were fitted with appropriate scooping devices for the water troughs introduced at the time to refill water during the journey. A further twelve class 9L locomotives followed in 1907. By widening the water tanks by three inches, they had a larger water capacity and the higher walls of the coal bunker meant that more coal could be carried.

The use in London did not last long, as the electric railcars could run at higher average speeds on competing routes and the steam locomotives therefore had to be more powerful. This led to the introduction of the class 9N with the 4-6-2T wheel arrangement from 1911. The 9K and 9L were subsequently moved to other locations and used, for example, on suburban routes from Manchester or in central England for regional trains. In 1914 and 1915, a 9L and a 9K were each fitted with a boiler with a superheater, but these initially remained one-offs.

9L No. 1120

Locomtive Magazine, July 1907

After the LNER took over operations in 1923, the classes were now designated C13 and C14. After a short time, shorter chimneys were installed to ensure suitability for the loading gauge of the entire LNER network. In addition, the scoops were removed because they weren't really necessary on short-haul routes. Between 1926 and 1935, all locomotives were given a new boiler with a superheater as part of the scheduled boiler replacement. British Railways took over all examples in 1948 and used them unchanged until the mid-1950s. New competition now arose in the form of the new diesel railcars, which soon made them superfluous. Almost all locomotives were scrapped between 1957 and 1959 and one locomotive of each class was used until 1960.

As a successor to the fast suburban Class 3600 “Birdcage”, Churchward developed a tank locomotive from the Class 3800 “County” by adding a trailing axle and storing water and coal supplies on the locomotive. It used the slightly smaller GWR Standard No. 2 boiler, which also had a Belpaire firebox and was tapered towards the front. Only number 2230 received the same County class boiler, but was also quickly upgraded to the smaller standard boiler.

The side water tanks had a forward sloping ceiling to match the tapered boiler barrel. They allowed the water capacity to be increased from the 1,500 gallons of earlier tank locomotives to 2,000 gallons, retaining good forward visibility. Scooping devices for water troughs were installed in both directions of travel in order to be able to fill up the water supplies more quickly during operation. Thanks to the driver diameter of 80.5 inches, the magazine “Die Lokomotive” still assumed in 1932 that it had to be the fastest tank locomotive in the world.

Between 1905 and 1912, three series of ten engines each were manufactured. The locomotives of the third series had a superheater installed ex works, and this was retrofitted to the first two series. Likewise, some locomotives were later provided with larger supplies. They were used in front of fast passenger trains in the suburbs of London.

Schematic drawing with dimensions

Locomotive Magazine, August 1905

Thanks to the large wheels, the engines were suitable for use on the outer suburban lines without many intermediate stops. At the same time, however, this meant that the acceleration was not sufficient for the inner suburban routes. Another point of criticism was the insufficient running smoothness, since the wheelbase of the two coupled axles was very small and there were large moving masses due to the long cylinder stroke of 30 inches. So it came about that the “County Tanks” were replaced by the “Large Prairies” of the 6100 class between 1931 and 1934. With their driver diameter of 68 inches and three coupled axles, these represented a better compromise between speed and acceleration. Since no better area of application could be found for the class 2221, they were all scrapped.

The I1 was built in two batches of ten locomotives each in 1906 and 1907 for the suburban lines in south London. They had a 4-4-2T wheel arrangement with a five foot six inch driving wheel diameter and a condensing apparatus for use in urban environments. In the second batch, the driving wheels and coupling rods of the class D1 were used, what shortened the wheelbase.

Occasionally they were also used as far as Brighton or hauled the royal train. However, they were bad steamers on suburban lines with short distances between stations. After being taken over by the Southern Railway, between 1925 and 1932 they received new superheated boilers left over from the rebuild of the classes I3 and B4. Now performing better only two were retired before 1948 and the the last ones of the remainder were used by British Railways until 1951.

By adding a trailing axle and reducing the driving wheel diameter by six inches, George Whale developed the Precursor tank class from the Precursor class tender locomotive. It was intended to pull heavy passenger trains on branch lines, but had an axle load that was too high for many branch lines. A total of 50 locomotives were built, the last 20 of which had smaller wheels.

Not only were the cylinders between the frames, but also the leading sandbox. For this reason, the latter was very difficult to refill, which is why a separate filler neck had to be attached to the outside. Since the locomotives could no longer be adapted to growing requirements due to their wheel arrangement, they were all retired between 1927 and 1940.

For the suburban lines in London, William Adams provided his class 46, which had outside cylinders, with an additional trailing axle in order to be able to accommodate larger coal supplies. Since this axle was in a radial axle box, the locomotive was nicknamed the “Radial Tank”. Four manufacturers delivered a total of 71 locomotives, the last of which had a boiler pressure of 160 instead of 140 psi. As early as 1895, the locomotives were replaced by other locomotives in their original area of operation, after which they were relocated to branch lines in rural areas. After the first were retired in 1916, the largest number only disappeared between 1923 and 1928 under the Southern Railway. Three locomotives even survived on the Lyme Regis branch until 1961, because initially no other suitable locomotives were found for the tight curves. One of these today belongs to the Bluebell Railway but is not operational.

Until 1880 the Great Eastern took over the operation on the lines of the LT&SR and thus also provided the locomotives. When this agreement expired, Thomas Whitelegg began developing a new passenger tank locomotive for the suburban trains. He enjoyed the help of William Adams, who was the former superintendent of GER and was now with the London & South Western.

The result was based on the LSWR class 46 tank locomotive with a 4-4-0T wheel arrangement. The same driving wheel diameter was used and a trailing axle was added, giving a 4-4-2T wheel arrangement for the first time on a British tank locomotive. Although the trailing axle was mounted directly in the frame, the axle bearings were radially adjustable and thus reduced the rigid wheelbase of the locomotive. As with the class 46, the cylinders were on the outside.

The first production lot was 18 locomotives, delivered by Sharp, Stewart & Co. in 1880 and 1881. The same company supplied twelve more in 1885. It was not until 1895 that Nasmyth, Wilson & Co. supplied another six. From 1902 at least four were equipped with a condensation device, while some received a roof specially adapted to tunnels. All locomotives not only came to the Midland Railway in 1912, but also to the LMS in 1923. Their decommissioning took place between 1929 and 1936.

In 1896, Neilson & Co. delivered two small 4-4-4T tank locomotives to the Burma Railways, which were designated class C. These had a axle load of less than eight tons and were fairly flexible with two two-axle bogies. They were oil-fired, but also had a small coal reserve. Their large firebox in relation to the tube heating surface indicates that they were well suited for commuter traffic with rapid acceleration and many stops.

The class 79 of the London, Tilbury & Southend Railway was a 4-4-2T tank locomotive for fast suburban trains. It was designed by Thomas Whitelegg on the basis of his class 37, that has in turn been designed based on William Adams' class 1. What all had in common was that they had outside cylinders and inside valve gear and a saturated boiler. With their 6 ft 6 in drivers, they could reach 65 mph (105 km/h).

The LT&SR only ordered four from Robert Stephenson & Co. which were delivered in 1909. When the Midland Railway took over the LT&SR in 1912, they were assigned to power class 3P. The next order of ten was placed by the MR, but only delivered directly to the LMS after the grouping in 1923. 25 more were ordered by the LMS in three additional batches and delivered between 1925 and 1930.

No. 80 “Southend-on-Sea”, later “Thundersley”, on a colorized post card

What was special was that even the last batch of this class was built in 1930 with a saturated boiler. Later they were removed from the earlier LT&SR network and used in the East Midlands. British Railways had taken over all 39 locomotives and withdrew them between 1951 and 1960. No. 80 from the first batch is the only one that's existing today. It is on static display at Bressingham and again carries its original livery.