Philadelphia & Reading 2-2-2 "Single" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class Black Diamond (Locobase 13926)

Data from DeGolyer, Volume 15, p. 122. See also "Museum polishes and shines a rare 'Black Diamond'", Trains, Volume 72, No. 4 (April 2012), p. 84 and GC Carter, "Black Diamond Inspection Locomotive", St Louis Museum of Transportation, last accessed 5 March 2012. (Thanks to Chris Hohl for his 18 January 2015 email update on the Black Diamond's restoration.) Works number was 10174 in August 1889.

The Trains report says that the Black Diamond was completed for use by Roland C Luther , General Superintendent of the Reading. From the outside, the inspection car/locomotive resembled an elongated "steam dummy" of the type then being sold to street-car lines in many cities. Note the "over-square" cylinders and relatively large grate, which was to burn "egg coal".

The body had doors at the rear for the engine crew and in the front face for the passengers. Fluted rubber matting covered both the steps and platform.

Black Diamond's appointments inside and ahead of the cab suited VIP passengers and included a leather "box seat" with drawers positioned at the rear over the boiler and against the partition. Other passengers sat in the 4 leather-covered seats that swiveled.

Baldwin's specs include walnut woodwork, "French plate glass" for the windows at front and read and in the partition. The glass inside for the side windows, which opened and were shaded by roller curtains, was to be of "good quality". So too was the carpeting to be of "good quality" and "in keeping with finish of engine". Even the bands on the boiler, which were planished (i.e., "Russian iron") in the cab, were brass in the passenger section. All hardware was nickel-plated, including Baldwin's builders card.

Painted in raw umber and gold and rolling on red wheels behind a red pilot, the little engine appears to have had an active career of less than 20 years, although details are indefinite. Carter's careful reconstruction leaves several acknowledged gaps, but tells the story of how the MOT gained final ownership quite well.

After sitting outside, but under a canopy for several years, the Black Diamond was taken into the shop on 15 December 2011 for cosmetic restoration and display in a new visitor's center. Chris Hohl, a volunteer at the Transportation Museum, reported that the restoration was completed in June 2012 and was put on display at the Roberts Building.

Specifications by Steve Llanso of Sweat House Media
ClassBlack Diamond
Locobase ID13926
RailroadPhiladelphia & Reading
Number in Class1
Road Numbers
Number Built1
BuilderBurnham, Parry, Williams & Co
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase
Engine Wheelbase 9.62'
Ratio of driving wheelbase to overall engine wheebase
Overall Wheelbase (engine & tender) 9.62'
Axle Loading (Maximum Weight per Axle)10080 lbs
Weight on Drivers9070 lbs
Engine Weight26350 lbs
Tender Light Weight
Total Engine and Tender Weight26350 lbs
Tender Water Capacity280 gals
Tender Fuel Capacity (oil/coal)
Minimum weight of rail (calculated)15 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter42"
Boiler Pressure160 psi
Cylinders (dia x stroke)8.25" x 8.5"
Tractive Effort1873 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.84
Heating Ability
Firebox Area
Grate Area 9.10 sq. ft
Evaporative Heating Surface
Superheating Surface
Combined Heating Surface0
Evaporative Heating Surface/Cylinder Volume
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation1456
Same as above plus superheater percentage1456
Same as above but substitute firebox area for grate area0
Power L10
Power MT0


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