Mason Bogie - Production and Service

Production and Service

Approximately 146 Mason Bogies were produced by William Mason's firm between 1871 and 1890 when the firm built its last locomotive, of which 88 or so were narrow gauge units, the rest being standard gauge. This was about half the firm's total output of locomotives during this period. Major buyers included the Boston, Revere Beach & Lynn Railroad, a suburban carrier which owned 32, the Denver, South Park and Pacific Railroad, a Colorado common-carrier railroad which owned 23, and the New York and Manhattan Beach Railroad, another suburban carrier, which ran seventeen locomotives of this pattern.

The best-known locomotives were those on the Denver, South Park & Pacific, and they rostered fairly large Mason Bogies, mostly of 2-6-6 and 2-8-6 wheel arrangements, and had a lot of success with them. Even here, though, the other problem with the Fairlie design showed itself, which was the surprisingly poor tracking of the powered bogie. It would both hunt, or wander, when on straight track, yet provide more resistance to turning when it hit curvature than might be thought. This manifested itself in much greater wear on wheels and track than might have been expected.

The type had its possibly most notable success on the aforementioned Boston, Revere Beach & Lynn, which liked Mason Bogies so much that it continued to purchase them even after the closure of the William Mason factory, ordering similar locomotives from other builders as late as 1914 and operating them until electrification in 1928. It must be said, though, that the special features of the Mason Bogie weren't really used in this application, since the line was not greatly curved and did not need the flexibility the Mason Bogie bought at the cost of quite some complexity.