Boston, Clinton & Fitchburg 0-6-6 Locomotives in the USA

Class Wm Mason (Locobase 5585)

Data from reproduction of 1950 reprint of 1883 Recent Locomotives as hosted by [] (visited 2 June 2003). See also "Some Old Mason Engines," Railroad & Locomotive Engineering , December 1900, p. 535. (Thanks to Chris Hohl for his 2 April 2023 email providing the various railroad name changes.) The boiler pressure is an estimate. Mason's works number was 536.

Ironhorse129's commentary notes that this was the first locomotive in the United States using Egide Walschaert's radial valve gear. Australian ferroequinologist and live-steam enthusiast David Fletcher wrote that the Stephenson gear normally used wouldn't work for an engine whose drivers pivoted on a bogie as this Mason Bogie did. The distance between the lifting rod, which controls cutoff, and the engineer's actuating Johnson bar would vary and the engine would speed up or slow down as a consequence. The Walschaert layout allowed for placing the lifting rod up in front of the steam dome in an arrangement that fixed the distance.

The writer of the RLE article praised the William Mason's pulling power, saying: "There is possibly no engine today, of her dimensions, that could, under the conditions of the day and time, equal this engine for the amount of work done. Had she not had a bogie of old design, the late J N Lauder would have repaired her .... The engine could haul 125 long freight box cars, such as were used at the time between Mansfield and Fitchburg, and the grades were heavy, so Mr Hobart Piper, her engineer, informs us. "

Chris Hohl documented the William Mason's several changes of ID: Ordered by the New Bedford Railroad, but delivered to the Boston, Clinton & Fitchburg #23 (the BC&F in was consolidated at the Boston, Clinton, Fitchburg & New Bedford in 1876.

The BCF&NB was absorbed by the Old Colony in 1883, which numbered the engine 108 At that time, the BCF&NB operated a total of 126.2 miles (203 km), which together with OCRR's mileage constituted the 617 miles (993 km).

Sources differ on the Wm Mason's fate. Some claim it remained on the OC roster at least until the OC merged with the New York, New Haven & Hartford. Those sources claim it took New Haven road #708. Locobase couldn't find any 0-6-6T in several New Haven rosters and considers it more likely that the OC scrapped soon after its 1883 takeover. Edson's New Haven roster shows the OC's motive power and reports the 108 as having been scrapped in 1887.

Another 0-6-6T, Canada Atlantic 724, was the first and only Mason Bogie to run on Canadian rails and the first Canadian engine to use Walschaert's gear. See [] . NB: For an explanation of the use of the singular "Walschaert", see Locobase 11157.