Data from Zerah Colburn (ed.), "Double-Bogie Locomotives for the Central Pacific Railway", Engineering, Volume 8, No 3 (16 July 1869), p. 35. See also Alexander Mitchell comments in Walton W Evans, "American and Fairlie Engines", Railroad Gazette, Volume 9 (30 September 1877), pp. 528-529.
Colburn's title reflects the original destination for this Double-Fairlie locomotive, but the Central Pacific refused delivery and the locomotive sat in Taunton, Mass for two years before the Lehigh Valley was persuaded to buy it. It was the LV that named the twinned cab, twinned firebox design after the Romans' two-headed god, who looked both into the past and into the future.
If he looked ahead, he would have seen that within a year, the Janus had aroused a strongly negative review from the LV's General Superintendent Alexander Mitchell. He wrote in an 18 July 1872 letter to W W Evans: "The Fairlie Engine 'Janus' has not satisfied me of her superior qualities over the old system ...I indorse [sic] statement of trial made on a steep grade, where with 130 lbs pressure, she developed 13 1/2 tons net tons tractive power, the eight-wheeled connected 20 x 24 in cylinders [the Consolidation layout recently devised by Mitchell and Baldwin Locomotive Company] developing 11 1/2 tons. The steam pipes have given much trouble from leakage, and I question their ever being kept tight. They are not to be depended on ... Could not recommend their adoption by any person or company" [ellipses in the original, which was excerpted by Evans].
So, despite reports of good work as a pusher and enjoying popularity among enginemen, the Janus enjoyed only a short career before being wrecked in 1877.
Principal Dimensions by Steve Llanso of Middle Run Media | |
---|---|
Class | Janus |
Locobase ID | 16400 |
Railroad | Lehigh Valley (LV) |
Country | USA |
Whyte | 0-6+6-0T |
Number in Class | 1 |
Road Numbers | 164 |
Gauge | Std |
Number Built | 1 |
Builder | William Mason |
Year | 1871 |
Valve Gear | Stephenson |
Locomotive Length and Weight | |
Driver Wheelbase (ft / m) | |
Engine Wheelbase (ft / m) | |
Ratio of driving wheelbase to overall engine wheelbase | |
Overall Wheelbase (engine & tender) (ft / m) | |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
Weight on Drivers (lbs / kg) | 108,000 / 48,988 |
Engine Weight (lbs / kg) | 108,000 / 48,988 |
Tender Loaded Weight (lbs / kg) | |
Total Engine and Tender Weight (lbs / kg) | |
Tender Water Capacity (gals / ML) | 3000 / 11.36 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 2.50 / 2 |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 30 / 15 |
Geometry Relating to Tractive Effort | |
Driver Diameter (in / mm) | 42 / 1067 |
Boiler Pressure (psi / kPa) | 140 / 970 |
High Pressure Cylinders (dia x stroke) (in / mm) | 15" x 24" / 381x610 (4) |
Tractive Effort (lbs / kg) | 30,600 / 13879.94 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.53 |
Heating Ability | |
Tubes (number - dia) (in / mm) | / 48 |
Flues (number - dia) (in / mm) | |
Flue/Tube length (ft / m) | / 3.36 |
Firebox Area (sq ft / m2) | 125 / 11.61 |
Grate Area (sq ft / m2) | 25 / 2.32 |
Evaporative Heating Surface (sq ft / m2) | 1775 / 164.90 |
Superheating Surface (sq ft / m2) | |
Combined Heating Surface (sq ft / m2) | 1775 / 164.90 |
Evaporative Heating Surface/Cylinder Volume | 180.75 |
Computations Relating to Power Output (More Information) | |
Robert LeMassena's Power Computation | 3500 |
Same as above plus superheater percentage | 3500 |
Same as above but substitute firebox area for grate area | 17,500 |
Power L1 | 2395 |
Power MT | 293.34 |