Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 23, p. 182. (Thanks to Chris Hohl for his 26 May 2017 email noting a mistake in wheel arrangement.) Works number was 18564 in January 1901.
The A&MR RR served the logging industry by delivering the product to Humboldt Bay. Built as plank road in the 1850s, the line later adopted this odd gauge (1,163 mm), roughly halfway between the 3' (914 mm) and standard gauge widths usually used in North America.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Hoopa |
| Locobase ID | 12463 |
| Railroad | Arcata & Mad River |
| Country | USA |
| Whyte | 2-4-0 |
| Number in Class | 1 |
| Road Numbers | 5 |
| Gauge | 3' 9.25 |
| Number Built | 1 |
| Builder | Burnham, Williams & Co |
| Year | 1900 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 6.25 / 1.90 |
| Engine Wheelbase (ft / m) | 12.33 / 3.76 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.51 |
| Overall Wheelbase (engine & tender) (ft / m) | |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 26,000 / 11,793 |
| Engine Weight (lbs / kg) | 32,000 / 14,515 |
| Tender Loaded Weight (lbs / kg) | 20,000 / 9072 |
| Total Engine and Tender Weight (lbs / kg) | 52,000 / 23,587 |
| Tender Water Capacity (gals / ML) | 800 / 3.03 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 22 / 11 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 37 / 940 |
| Boiler Pressure (psi / kPa) | 160 / 1100 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 10" x 16" / 254x406 |
| Tractive Effort (lbs / kg) | 5881 / 2667.58 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.42 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 106 - 1.5" / 38 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 6.46 / 1.97 |
| Firebox Area (sq ft / m2) | 43 / 4 |
| Grate Area (sq ft / m2) | 8.19 / 0.76 |
| Evaporative Heating Surface (sq ft / m2) | 308 / 28.62 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 308 / 28.62 |
| Evaporative Heating Surface/Cylinder Volume | 212.41 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 1310 |
| Same as above plus superheater percentage | 1310 |
| Same as above but substitute firebox area for grate area | 6880 |
| Power L1 | 3559 |
| Power MT | 603.56 |