From Germany's Bimmelbahn Forum, I have the following news item:

At the beginning of 2024, a container ship coming from North America with freight of railway historical value will dock in a German port. One of the containers contains what is probably the smallest steam locomotive ever built for a commercial railway in the world. In addition, built in 1896, it is one of the oldest originally preserved German locomotives and the only surviving locomotive of its 5 HP design.

The 600mm royal blue two-axle and only 1.7 t light tiny locomotive was built With the dimensions of a small car, the former Jung locomotive factory in Jungsthal near Kirchen an der Sieg under the work number 255 for an entrepreneur named Fernando de Teresa, who ran an amusement park in Mexico City between 1896 and the outbreak of the revolution in 1910 and who probably also took visitors with him The 600mm narrow-gauge field railway “Ferrocarril de Tacubaya” with a length of 1.6 km was transported into and through the park by Krupp from the Magdeburg factory. The locomotive only has 5 hp (for comparison: the largest steam locomotives used in Germany had around 3000 hp and weighed around 140 t) and pulled 3-4 delicate cars before the US locomotive factory Baldwin built a larger 2B tender in 1897 under the work number 15241 -Steam locomotive named “Susana” delivered to the park as a replacement. With the revolution, the railway vehicles were scattered to the four winds and the rumor persisted that they were still present in Mexico. After around 20 years of research, the Frankfurter Feldbahnmuseum e.V., with the help of a Mexican friend, was able to locate little Jung as a "decorative object" in the anteroom of the boss of a small machine factory near the international airport in Mexico City in the spring of 2023.where, since it was found at a car dealer in the 1940s, it had remained functional since around 1955 in an unchanged complete and absolutely original condition - i.e. a kind of "barn find". The older owner sold it to the Frankfurter Feldbahnmuseum e.V., which wants to put the locomotive back into operation. It will probably be presented to the public for the first time as part of the operating day on January 14th, 2024. If you google the railway, you will also find operational pictures of the locomotives from around 1900. Jung, like most German locomotive manufacturers, built his storage locomotives with an output of at least 10 hp. Only 11 examples of the locomotives of the even smaller performance classes 5, 6 and 8 HP were built there (bore of the cylinders of the 8 HP locomotive 11.0 and 9.0 cm for 6 HP and 8.5 cm for 5 HP).

It's a pity I can't get the image to post --- it shows what looks very similar to an LGB engine, about the size of a VW bug, sitting in the waiting room of a small machine shop in Mexico City. This after hearing for years that it is illegal to export steam locomotives from Mexico because they are covered by "national patrimony" laws...

From Mexico I have just received the clarification that "national patrimony" only applies to locomotives owned by the Mexican government, or other public entity, which owned most of the railroads in the republic.

Found one photograph (via Wikipedia) of this railroad, featuring both locomotives, the 0-4-0 Jung, and the Baldwin 4-4-0. If this photo is any indication, this railway was a jewel, and that included its motive power.

General Wikipedia entry.

https://en.wikipedia.org/wiki/Tacubaya_Railroad

That 4-4-0 looks an awful lot like a Mt. Getna narrow gauge engine.

The Mexico City Baldwin (600 mm ga.) has a lower boiler than the Mt. Gretna Baldwins (610 mm ga.)

While we're doing small, Wikipedia reports the Ferrocarril de Tacubaya Baldwin 4-4-0, at 6 tons, was the smallest ever built by Baldwin for commercial purposes.

The US lines were in in Lebanon County PA. The Mt. Gretna Narrow Gauge ran from 1889 to 1916 while the Standard Gauge parent Cornwall and Lebanon ran from 1850 to 1972 when washed out by Hurricane Agnes as part of Penn Central. There were iron ore deposits in Cornwall and the RR replaced a plank road connection to the Union Canal.

Phil Mulligan

Here is the Baldwin builder's photo of the Tacubaya 4-4-0, 'Susana'. Not only was she really small, but her proportions resembled a scaled-down standard gauge locomotive rather than a typical two-footer, which made her look like a live steam model or park locomotive. For instance, the bell can't have been more than 5 or 6 inches in diameter.

-Philip Marshall

Here's one with a person for scale.
From Facebook?

The photo looks like it was shot while the camera tripod was still in the same place as the photo above.

The monstrous Mt Gretna Engines had 33" drivers. This one had 23" drivers.

Thanks for posting those pictures. You got to admit that Susana looks like she was thrashed with a cuteness wand. And just the right size to work on, too...