Boston & Lowell 2-2-0 "Planet" Type Locomotives

Class Details by Steve Llanso

Class Patrick (Locobase 802)

An 1899 Locomotive History reproduced on gives the details (except for the boiler pressure) of this Planet type. See also Angus Sinclair, Development of the Locomotive, pp. 179-180. Railway & Locomotive Historical Society Bulletin #13 (1927) has a report by the railroad of this engine's performance.

The entry notes that the fireboxes in the class varied in depth from 3' 1 1/2" to 3' 3" deep giving heating surfaces of between 36.8 to 38.36 sq ft. The stack had two 1 1/2"-diameter blast pipes.

The other locomotives in the class were Concord, Nashua, Medford, and Suffolk. Sinclair adds that a government commission reporting on railroads in New England said that 35 of this type were then in use. Some were later rebuilt as 2-2-2s by adding a trailing axle under the firebox.

Specifications by Steve Llanso
Locobase ID802
RailroadBoston & Lowell
Road Numbers
BuilderLowell Manufacturing Co.
Valve Geardrop-hook
Locomotive Length and Weight
Driver Wheelbase
Engine Wheelbase
Ratio of driving wheelbase to overall engine wheebase
Overall Wheelbase (engine & tender)
Axle Loading (Maximum Weight per Axle)14448 lbs
Weight on Drivers14448 lbs
Engine Weight23072 lbs
Tender Light Weight14896 lbs
Total Engine and Tender Weight37968 lbs
Tender Water Capacity
Tender Fuel Capacity (oil/coal)
Minimum weight of rail (calculated) on which locomotive could run24 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter60"
Boiler Pressure70 psi
Cylinders (dia x stroke)11" x 16"
Tractive Effort1920 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 7.53
Heating Ability
Firebox Area38.36 sq. ft
Grate Area 6.71 sq. ft
Evaporative Heating Surface304 sq. ft
Superheating Surface
Combined Heating Surface304 sq. ft
Evaporative Heating Surface/Cylinder Volume172.74
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation470
Same as above plus superheater percentage470
Same as above but substitute firebox area for grate area2685
Power L11972
Power MT300.91


Introduction and roster provided by Richard Duley. Class details and specifications provided by Steve Llanso of Sweat House Media.