In Whyte notation, a 2-4-4 is a steam locomotive with two unpowered leading wheels followed by four powered driving wheels and four unpowered trailing wheels. It is known as the Mason, other equivalent classifications are, UIC classification, 1B2 French classification,122 Turkish classification,25 Swiss classification, 2/5 The equivalent UIC classification is 1B2. This unusual wheel arrangement does not appear to have used on the mainline railways in the UK. It was however one of the used on the Mason Bogie articulated locomotives. Five examples were constructed at the Mason Machine Works for the narrow gauge Boston, Revere Beach, the railway subsequently received twenty-one further examples between 1900 and 1914, constructed by the Taunton Locomotive Manufacturing Company, Manchester Locomotive Works, and ALCO. Four 2-4-4T passenger locomotives were built by the Czechoslovak Škoda for Lithuania in 1932 and they were seized by the USSR in 1940, then by the Germans. One was used after World War II in Poland as the OKf100-1 until 1950, other tank locomotives with 2-4-4T arrangement, Bavarian D XII French T56601 -6637 of AL railway
Image: BRBL 6 Bldr
Diagramatic representation of 2-4-4. Front of engine to the left.