The “Edward Patterson” was built in May 1872 by Baldwin with the works number 2819 for the Ashland Iron Co. in Kentucky. It later came to Maryland Steel. It was a small two-axle saddle tank locomotive that was nevertheless powerful thanks to its small drivers. Locomotives in this size were built by several manufacturers and were used from the second half of the 19th century in large numbers by industrial, agricultural and forestry operators. In many places, they replaced draught animals, which increased transport capacity and reduced costs.

The Avonside Engine Company offered a range of standard narrow gauge tank locomotives that could be ordered with various gauge and cylinder diameter combinations. In order to ensure a long service life and low wear, some assemblies were made of harder steel than actually required and the friction surfaces on wear-intensive parts were made wider.

At the lowest end of the size scale, a four-coupled shunting locomotive was available, which was built in gauges between 1 foot 6 inches and 3 feet 6 inches. Cylinders were available in six, seven or eight inch diameters. Since there were otherwise no adjustments to customer requirements, larger quantities could be pre-produced and delivered directly on demand. No further information is available on the illustrated locomotive with the name “Imperial”.

In order to do something about the inefficient use of old steam locomotives in shunting service, the I e was designed for the Württemberg State Railway as a four-coupled tank locomotive. During development, however, attention was also paid to the fact that the engines could be used in line service on branch lines if required. They were designed as a cost-effective and purposeful construction. By using the 20 mm thick plate frame as a water tank, the coal bunker could be moved in front of the driver's cab, which reduced the overall length of the locomotive.

On the boiler barrel, the steam dome and the regulator were separate from each other, with a sandbox between them. The Allan valve gear had to be on the outside and the drive was on the second axle. With a driving wheel diameter of 1,235 mm, speeds of up to 60 km/h could be reached. In addition to a modern air brake, some of the machines also had a countersteam brake.

30 were delivered in several batches, of which 25 units were taken over by the Reichsbahn in 1925. Together with the I b taken over from the Pfalzbahn, they were classified in the class 88⁷⁵. By 1930 all were retired or sold to private operators. One example was on Austrian territory after the end of the Second World War after it had been used by a construction company. It was taken over by the ÖBB and used until 1956, making it the last representative of the I e.

The Deggendorf Railway had already procured two four-coupled tank locomotives from 1866, which were used for shunting at large stations. Based on these, the Bavarian Eastern Railway procured five similar examples from the following year, which were significantly heavier. These were first designated as class D and later as D IV at the state railway and served as a model for the D IV of the state railway.

The latter was procured between 1875 and 1897, which is why it could later be found at almost every larger Bavarian station. During this time, changes were made in production, so the driver's cab, which was initially open at the back, was closed in later series. Like many other light tank locomotives, the D IV had external Stephenson valve gear and a water tank inside the frame. It was the first Bavarian locomotive with this arrangement of the water tank and thus became the model for many others.

A total of 46 of this type were manufactured by Maffei and 86 by Krauss. The Pfalzbahn had another 31 almost identical locomotives made by the same manufacturers and designated them as T 1. In 1925, a total of 122 remaining machines were assigned to the 88^71-72 series. They were phased out by the early 1930s.

The D VI was a four-coupled tank locomotive for local railways, which had been developed together with the D VII. It was intended for railway lines with a maximum axle load of up to 12 tonnes on the level, while its sister was intended for branch lines with more gradients. Between 1880 and 1894, Krauss and Maffei delivered a total of 53 vehicles.

Despite the small size, the locomotives benefited from modern developments. Vacuum brakes were already installed in the first examples, later even air brakes. For easier accessibility during maintenance, running boards were used for the first time on a Bavarian locomotive. Sometimes there was also a connecting bridge to the train. Initially, there were no storage tanks on the side, instead 500 kg of coal were accommodated in the driver's cab and 1.8 m³ of water were in the frame, which was designed as a water tank. The last nine machines received storage tanks on both sides of the boiler, which increased the capacities to 800 kg or 2.3 m³.

With 26 machines, the Reichsbahn received about half of the originally built ones, which were then classified as class 98⁷⁵. Their service there ended in the 1920s, but a few examples were sold to works railways. The last example was the former 98 7508 that was in use at the Raubling peat works until 1964. This locomotive is now maintained by the DGEG and again has the number 1222 of the K.Bay.Sts.B. and the name “Berg”.

In 1905, Krauss and Maffei each had a type of four-coupled local railway locomotive developed, which was intended to enable economical operation, especially with light passenger trains, and should be operable by just one person. The PtL 2/2 was designed by Maffei and was able to assert itself against the ML 2/2 from Krauss.

The basic idea behind the design of the locomotive was a spacious, centrally located driver's cab and the use of a semi-automatic dumping device to load the grate with coal. The boiler and attachments were arranged in such a way that the driver could leave the driver's cab on both sides and reach the wagon train directly via a running board. In addition, despite the small dimensions of the locomotives, a smoke tube superheater was already used in order to take advantage of the still young superheated steam technology. The boiler was almost entirely inside the driver's cab, only the smokebox and chimney sticking out at the front, and at the back one could see the end of the firebox and the coal bunker with the built-in chute. The very generous dimensions of the driver's cab and the large windows earned them the nickname “Glaskasterl” or “Glas-Chaise” in Franconia, whick both stands for “glass box”.

Three batches were produced, which differed mainly in terms of the engine. The first six machines from 1905 and 1906 had the cylinders inside the frame, which proved to be too maintenance-intensive. Therefore, these vehicles were already retired in 1923.

Original variant

Die Lokomotive, September 1906

From the second batch, the cylinders were on the outside, which significantly simplified maintenance. In addition, space was now free within the frame for the water tanks, which had previously been located above the frame next to the boiler. As a side effect of this changeover, there was now more space on the running boards. In order to be able to do without long connecting rods despite the long wheelbase, the power was first transmitted to a jackshaft between the axles. A total of 29 vehicles of this variant were built in 1908 and 1909.

The last batch consisted of nine and four locomotives, which were delivered in 1911 and 1914. With these, the wheelbase was shortened by 50 cm, which meant that the jackshaft could now be dispensed with. Instead, the drive was on the second axle. The total length was also reduced by about 20 cm.

The Reichsbahn took over nine examples of the second batch and all 13 of the third batch. They were classified as class 98³ and given the numbers 98 301 to 98 322. In the period leading up to the end of the Second World War, some machines were sold to private railways and one to Austria. The latter was used by ÖBB as road number 688.01 until 1959. On behalf of a Lower Saxony light railway, a locomotive was provided with conventional layout until 1950, i.e. with a driver's cab at the end of the boiler. The fittings were moved to the back of the firebox and the switch to manual grate loading took place. The remaining machines came to the Bundesbahn after the war and were mostly retired in the fifties, but the last survived until 1963. Today there are still two PtL 2/2, but they are no longer operational. One of them is in the steam locomotive museum in Neuenmarkt-Wirsberg and the other is in the DB Museum in Koblenz as a functional cross-section with the boiler cut open in the middle.

The ML 2/2 was a local railway tank locomotive that was built by Maffei between 1906 and 1908 as an alternative to the more well-known PtL 2/2 by Krauss. Although it was a very small and light locomotive, it was fitted with a very complicated and difficult to maintain powerplant. The “M” in the designation goes back to the term “motor locomotive” and serves as a reference to the powerplant with opposed pistons. There was a cylinder on each side between the widely spaced axles, the counter-rotating pistons of which acted on both wheel sets with short connecting rods. Inside the frame were the coupling rods that connected the axles.

With this special arrangement, the prospect of a perfect load balancing was presented. The maximum car load at 50 km/h on the level was 65 tonnes. The same load could still be pulled on a gradient of 2.5 percent at around ten to twelve km/h.

Otherwise, the ML 2/2 was designed to be just as suitable for everyday use as other Bavarian local railway locomotives. In order to be able to do without a fireman, there was a dumping device for semi-automatic loading of the grate. Passenger cars could be entered from either side of the locomotive. On a towed train, the gangway consisted of a door at the rear of the cab. However, if the train was pushed, the transition could be reached via a running board on the sides of the boiler. For this purpose, the water tanks were narrow and elongated so that they could be walked past without any problems.

24 examples were built for the Bavarian State Railways, three of which were sold to the firebrick factory in Marktredwitz in 1922. The rest were retired in 1924 because the maintenance of the internal parts of the engine was too expensive. The planned transfer to the Reichsbahn numbers 98 361 to 98 384 therefore did not take place. In 1907, the Hungarian MÁV had two ML 2/2 built under license for suburban traffic in Budapest. In contrast to the Bavarian engines, they had an certified maximum speed of 60 km/h, since the complicated powerplant was expected to run smoother.

The Darjeeling Himalayan Railway's best-known and longest-lasting locomotive is the class B, which was built by several manufacturers from 1889 and is still in use today. Although the DHR had also procured larger locomotives and even Garratts, these small, two-axle saddle tank locomotives had apparently been best suited to the steep two-foot line with radii up to 60 feet. 

The coal capacity was later increased by planks. Due to the low quality of coal available and the cheap labor in India, the crew of these locomotives consists of up to six people. In addition to the driver, this includes two people who sit on the buffer beam and spread sand on the rails by hand. The fireman is assisted by one person who breaks the coal into equal-sized lumps and another who passes the coal to the fireman.

Locomotive Magazine, September 1918

The 34 class B members, supplied by British and American manufacturers, took on the brunt of the traffic over the decades. In 1997 they were reinforced by diesel locomotives as their number decreased due to age. Today most regular trains are pulled by the diesel locomotives, while class B mainly only takes on tourist trains. A locomotive came to the Beeches Light Railway in Great Britain around 2000, where it was used until the line closed in 2023.

The class 88 of the kkStB designated small tank locomotives intended for traffic on branch lines. They drew their inspiration from five 0-4-0T locomotives built for the Kaiserin-Elisabeth-Bahn in 1880, which were also called class 88 at the beginning and were renumbered to class 188 in 1905. The new class 88 was built 47 times by Krauss in Linz between 1882 and 1885.

The last five were built for the Österreichische Lokaleisenbahngesellschaft (ÖLEG) and were slightly heavier than the 42 of the kkStB. Starting in 1892, they got new boilers. After World War I, they came to the state railways of Czechoslovakia, Italy, Poland, Romania and the Kingdom of Serbs, Croats, and Slovenes.

While there were many small standard locomotives for the narrow gauge lines in quarries, some customers had special requirements. One of these was the Moel Tryfan quarry in North Wales that had an access tunnel that required the locomotives not only to be narrow, but also to have a maximum height of six feet (1.829 mm). So Hunslet delivered two locomotives in 1902 and 1904 which were based on the Alice class and tailored to these requirements. The first one was named “Tryfan” after a nearby mountain and the second one carried the name of Cadf#

an, a Welsh saint.

Like the Alice class, they were 0-4-0T saddle tank locomotives. To reduce their height, the floor of the cab was lowered as much as possible. To protect the crews in the tunnel, the cab had no windows on the sides. As a result, “Tryfan” had a total height of exactly six feet, while “Cadfan” was even a bit lower. During their lives, at least “Cadfan” was once loaned to a neighboring quarry. Both were scrapped in 1941.