Under the Whyte notation for the classification of steam locomotives, 0-4-4 represents the wheel arrangement of no leading wheels, four powered and coupled driving wheels on two axles, and four trailing wheels on two axles. This type was only used for tank locomotives.
In American cities, the type known as a Forney locomotive, was used on the narrow curves of elevated railways and other rapid transit lines. In the UK 0-4-4 tanks were mainly used for suburban or rural passenger duties.
Finland[]
The Finnish Steam Locomotive Class F1 entered service with SVR in 1885 were used until 1935. One example survive it is preserved at the Finnish Railway Museum.
United States[]
Cora-Texas Plantation Co. No. 1 an 0-4-4T is on display at the Forney Transportation Museum.
The 0-4-4 configuration appears to have been introduced in the US, with the Forney locomotive, was patented by Matthias N. Forney between 1861 and 1864. These were characterized by a single frame under the boiler and fuel/water tank, which is supported at the rear by the truck under the coal bunker/water tank. The locomotives were designed to run cab (or bunker) first and were built for commuter lines in cities such as New York, Chicago and Boston.