Philadelphia & Reading 2-4-2 "Columbian" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class M1-a/M1-b (Locobase 8879)

Data from TraitT pratique de la machine locomotive ... By Maurice Demoulin, 1898

Librairie polytechnique, Baudry et Cie, p 380 and Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 18, p. 137.Additional data from 1907 Catalogue of Mechanical Engineering Collection in the Science Division of the Victoria & Albert Museum (Board of Education South Kensington)., pp 92. Baldwin works numbers were 12433 in January 1892; 12672, 12676, 12679-12680 in May; 13370 in April 1893; 13408-09, 13411-13413 in May.

In its catalogue of exhibits for the 1893 Exhibition, Baldwin made "special mention" of the suppliers of materials and appliances to this design:

Boiler and fire-box steel Wellman Iron and Steel Co., Thurlow, Pa.

Tubes Reading Iron Co., Reading, Pa.

Tires Standard Steel Works, Philadelphia, Pa.

Wrought-iron wheels (Vauclain pattern) Standard Steel Works, Philadelphia, Pa.

Metallic packing United States Metallic Packing Co., Philadelphia, Pa.

Sight feed-lubricator Detroit Lubricator Co., Detroit, Mich.

Injectors William Sellers & Co., Incorporated, Philadelphia, Pa.

Driving brake American Brake Co., St. Louis, Mo.

Tender and train brake . . Westinghouse Air Brake Co., Pittsburgh, Pa.

Tender-coupler The Hazleton New Universal Interlocking Coupler Co.,

As unusual as the adoption of the Bicycle wheel arrangement was in the US, production of ten Bicycles with the four-cylinder Vauclain compound layout in a camelback profile was rarer still. They didn't persist in this arrangement for long.

One (682) was rebuilt as an Atlantic in May 1899, the others as N-4a camelback Moguls in 1904; see Locobase 12664.

Specifications by Steve Llanso of Sweat House Media
Locobase ID8879
RailroadPhiladelphia & Reading
Number in Class10
Road Numbers618-622, 679-684 / 301-309
Number Built10
BuilderBurnham, Williams & Co
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase (ft) 7.50
Engine Wheelbase (ft)23.25
Ratio of driving wheelbase to overall engine wheebase 0.32
Overall Wheelbase (engine & tender) (ft)
Axle Loading (Maximum Weight per Axle) (lbs)
Weight on Drivers (lbs)84,023
Engine Weight (lbs)131,748
Tender Loaded Weight (lbs)92,000
Total Engine and Tender Weight (lbs)223,748
Tender Water Capacity (gals)4755
Tender Fuel Capacity (oil/coal) (gals/tons) 5.50
Minimum weight of rail (calculated) (lb/yd)70
Geometry Relating to Tractive Effort
Driver Diameter (in)78
Boiler Pressure (psi)180
High Pressure Cylinders (dia x stroke) (in)13" x 26"
Low Pressure Cylinders (dia x stroke) (in)22" x 26"
Tractive Effort (lbs)12,777
Factor of Adhesion (Weight on Drivers/Tractive Effort) 6.58
Heating Ability
Firebox Area (sq ft)173.46
Grate Area (sq ft)76
Evaporative Heating Surface (sq ft)1435
Superheating Surface (sq ft)
Combined Heating Surface (sq ft)1435
Evaporative Heating Surface/Cylinder Volume359.27
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation13,680
Same as above plus superheater percentage13,680
Same as above but substitute firebox area for grate area31,223
Power L14710
Power MT247.16


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