After a few months in service with the “Rocket”, Stephenson used the experiences to develop an improved successor. Since the placement of the cylinders of the predecessor was unfavorable for the running characteristics, the driving axle was moved to the rear and the cylinders were installed horizontally in front of the driving axle and inside the frame. It was probably the first locomotive with this arrangement, which later became the standard.

This arrangement not only improved the running characteristics, but also allowed the cylinders to be mounted inside the smokebox, thereby reducing losses from condensation. Also new was a steam dome, with which dryer steam could be extracted from the boiler. In addition, the front and rear buffers and couplers were roughly in the places where they are today.

On November 23, 1830, it was able to prove its performances by completing the 31 miles from Liverpool to Manchester in about an hour. The prototype was followed by six more by Stephenson and three made by Fenton, Murray and Jackson to the same design.

In the years that followed, many locomotives were built in several countries based on the “Planet” pattern, so that the 2-2-0 wheel arrangement was later named after it. The Liverpool & Manchester alone got 16 of them. The original “Planet” was first modernized in 1833 and retired in 1840. A replica that was built in 1992 was used regularly until 2017.

One of the most significant locomotives of all times was the „Rocket”, built in 1829 by George and Robert Stephenson for the Rainhill Trials which were held by the Liverpool & Manchester Railway. In these trials, the L&MR wanted to determine the design for a locomotive that could successfully operate light passenger trains over longer distances. The new locomotive had to achieve an average speed of 10 mph (16 km/h) over the 70 miles from Liverpool to Manchester and back. The limit for four-wheeled locomotives was set to four and a half tons, while six-wheeled locomotives were limited to six tons.

Since the Stephensons recognized that a single driving axle would be enough for the light trains, they chose the 0-2-2 wheel arrangement for the first time. In this case the driving axle was at the front and the cylinders were mounted behind it at an angle of 38 degrees. The rear wheels were not connected to the driving wheels and only carried the weight of the firebox. 

The boiler had many features which could be found on later steam locomotives. Instead of a single or two flues, it had 25 tubes which created more surface for the smoke to heat the water. These worked great in conjunction with the blast pipe to provide enough draught. Additionally, the firebox had a water jacket to utilize the direct radiant heat from the hottest part of the boiler.

“Rocket” easily won against its rivals in October 1829 and so the Stephensons could share the £500 prize with Henry Booth from the L&MR, who had provided valuable input for the design. It took part in the opening of the railway on September 15, 1830 when the Stephensons had already built the even more advanced “Northumbrian”. The event was overshadowed from an accident in which “Rocket” struck and killed William Huskisson, the MP for Liverpool.

In 1831, when some similar locomotives had already been built, the cylinders of “Rocket” were mounted in a more horizontal way to match “Northumbrian”. It was used on the L&MR until 1834 and then it was unsuccessfully used by Thomas Cochrane to test steam turbines. Rebuilt back to conventional cylinders, it was sold to the Brampton Railway in 1836 and used there until 1840.

After a period of storage, it was donated to the Patent Office Museum (Science Museum) at London in 1862, where it rested until 2018. After some time in the NRM at York, it came to Shildon in 2023. Over the years, several working and stationary replicas have been built. The most popular replica was built for the 150th anniversary in 1979. The original locomotive can today be seen with its nearly horizontal cylinders, while this replica still has them inclined by 38 degrees.

Francis Webb developed the 17 inch coal engine in the early 1870s as his first design for the LNWR. It was created under the requirement that production and operation should be as cheap as possible. These three-axle machines were sometimes described as the simplest and cheapest in the country, but on the other hand they were generally extremely successful with typical British maintenance. A total of 499 were built in 19 years.

One locomotive demonstrated that it could be built, including building up steam, in 25.5 hours. They could pull coal trains of 541 tons at a speed of 25 mph. From 1905 onwards, 45 were rebuilt into saddle tank locomotives. During the First World War, many were used by the military abroad, some even in Palestine. The LMS took over almost half in 1923, the British Railways received 35 in 1948 and used the last until 1953.

In 1880, Francis Webb introduced a new class of goods locomotives for the LNWR. Based on his 1873 “17 inch coal engine”, it had larger cylinders, a slightly larger boiler with a higher pressure and larger driving wheels. The official name of the new class was “18 inch Goods Engine” due to the cylinder diameter, but it was also called “5 ft 0 in Express Goods” due to the size of wheel centers.

Within 22 years, 310 locomotives have been built. Due to their large LNWR crest on the splashers, they got the nicknames “Cauliflower Class” and “Crested Goods”. With the grouping in 1923, they were put into LMS power class 2F. At this time, only two had been withdrawn. British Railways still inherited 69 in 1948 and withdrew the last ones in 1955. A class that had been derived from this class was the 0-6-2T “18 inch Tank Class”.

By reducing the driving wheel diameter from 75 to 62.5 inches, George Whale, superintendent at the LNWR, developed a locomotive for mixed service from his Experiment class. The resulting class reached a total of 170 and was officially referred to as “19in Express Goods,” a reference to the cylinder diameter and its primary intended use in front of express goods trains.

Because of their origin they were also called the “Experiment Goods Class”. They were classified by the LMS into power class 4F and were withdrawn from service from 1931. British Railways only took over three locomotives, which disappeared by 1950.

This class consisted of 220 2-4-2T tank locomotives built for local passenger trains at Crewe between 1879 and 1898. The designation came from the diameter of the wheels at the centres, while the tires measured four feet and 8½ inches. The class was designed by Webb from the class 2234 of 2-4-0T locomotives by adding a trailing axle and larger supplies. The boiler and wheelbase were still the same. 20 members, like the pictured one, were fitted with a condenser. Since the new class reached a larger number than the original one, the class 2234 was later called “Chopper Tanks” as it looked like a chopped 4ft 6in Tank.

In 1902, six were sold to the Dublin, Wicklow and Wexford Railway and re-gauged to broad gauge. 14 years later, five were sold again to the British Government and again re-gauged to standard gauge. Four others were sold to the Wirral Railway in 1913, followed by one each which were sold to the Cardiff Railway and Cromford and High Peak Railway.

Many of the locomotives still with the LNWR were fitted with push-pull equipment from 1909 and called “Motor Tanks”. As many were withdrawn from this time, only 90 were taken over by the LMS in 1923. There they were assigned power class 1P. More withdrawals started in the following year and the last one was gone in 1936.

The “4ft Shunter” was a class of dock shunters designed by John Ramsbottom with drivers of four feet or 1,219 mm. They had an 0-4-0 wheel arrangement and a saddle tank. Their cylinders measured 14 by 20 inches and the boiler was of the launch type with cylindrical firebox. As this firebox did not project downwards, there was enough space to move the rear axle further to the rear. 26 were built at Crewe between 1863 and 1865, ten in 1870, ten in 1872 and the final ten in 1892.

Three from the final batch were rebuilt into 0-4-2ST cranes. One of these was 3248 that can be seen in the photo. Many of the unrebuilt shunters were withdrawn between 1925 and 1933. Others survived and were provided with new boilers in the thirties. Most others were withdrawn in the late forties and the last ones in the early fifties. 1439, later numbered 3042, was preserved as the only one and is on display at the Ribble Steam Railway.

The 5ft 6in Tank was a 2-4-2T locomotive designed by Webb for fast passenger service. In general, it was a tank version of Webb's Precursor class. The wheels actually had a diameter of 5 feet and 8½ inches with tires and the 5 feet and 6 inches from the class designation only stood for the diameter of the wheel centres. The cylinders were 17 inches in diameter and 24 inches in stroke and were operated by Allan valve gear.

The LNWR built 160 between 1890 and 1897 in their Crewe shops. When the LNWR became part of the LMS in 1923, only three had been withdrawn. They were now assigned to power class 1P and between 1929 and 1932, 42 were fitted for working push-pull trains. Two were sold to the War Department in 1930 and 1931. When British Railways were founded in 1948, only 43 were remaining. The last ones were withdrawn in 1955 and none were preserved.

Webb developed the Alfred the Great class as an enlarged development of the Jubilee class. Like these, it had a four-cylinder compound engine. A redesign of the valve gear made them the Benbow class. After the Jubilees had been converted into two-cylinder simples, the same thing happened to 25 of the 40 Benbows from 1913 onwards. These, like the rebuilt Jubilees, came to the Renown class. 39 locomotives came to the LMS, the rest were retired by 1923.

Instead of ordering another batch of the class 1185 with a 0-8-2T wheel arrangement, H.P.M. Beames developed the class 380 with a two-axle trailing bogie to get more space for the supplies. Their area of application was the steep and winding lines in the valleys of South Wales, on which they were to pull freight trains and, if necessary, also be used in front of passenger trains. When the locomotives were delivered, the LNWR had already been merged into the LMS, where they were classified in power class 5F. 14 of the 30 locos survived the founding of British Railways, but these were retired by 1951.