The American licensee of the Fairlie Patent steam locomotive was the firm of William Mason, located in Taunton, Massachusetts.
In 1869, a Single Fairlie locomotive 0-4-4T had been designed and constructed by Alexander McDonnell for the Great Southern and Western Railway in Ireland.
[1][3] Mason redesigned the faulty castings and designed a new delivery system, in which the pivot point for the leading truck became a hollow ball joint through which the live steam for the cylinders passed.
Additionally, the reversing shaft had to be mounted on top of the boiler, with a long lifting link dropping down to the radius rod, a feature unique to Mason Bogies due to the rotating truck and tight clearances.
"[9] Copies of the DSP&P's biggest engines were built for the Denver, Utah & Pacific, which sold them to the Burlington and Northwestern Railway, a CB&Q subsidiary in Iowa.
[1] Only one Mason Bogie, Torch Lake, survives, at Greenfield Village (part of The Henry Ford) in Dearborn, Michigan, a standard gauge 0-6-4.
Like the Mason Bogie, the Forney has powered axles under the boiler and a trailing truck under the rear bunker and tank behind the cab.