>>983787>It's a compound, high and low pressure cylinders on each side, four cylinders total.Compound engines really are not that strange, not with 4 cylinders either. You'll find compound engines, even of 4 cylinders, in any country. Well, except for the UK since they didn't really need to, but they were very common in Germany and Austria-Hungary, as well as Switzerland and France.
Pic related. The NSB type 26c was designed to climb the Norwegian mountains on the Bergen route to and from Oslo. Type 26a and 26b were quickly modified to be compound locomotives to reduce the enormous coal usage, and the 26c came to be one of the most versatile steam engines in this country's history.