Data from Soo 9 - 1930 Steam Locomotive Diagrams supplied in May 2005 and August 2013 by Allen Stanley from his extensive Rail Data Exchange. Stanley later added Soo 3-1909 Classification of Locomotives in August 2013. (Thanks to Chris Hohl for his 13 Auguat 2020 email noting the Soo's preference for "renumbered", a later change in driver diameter, and the reductions in fuel and water capacities when the 325 reverted to a tank locomotive layout.) Rhode Island works number was 1877.
Like the 0-4-6T locomotive built for the same railroad at the same time (1887), this engine merited inclusion nevertheless because it was based on Matthias Forney's tank locomotive design. Compared to the smaller four-coupled Y, the H used more boiler, but less firebox and grate. At some later date, the drivers were fitted with thicker tires that increased diameter to 50" (1,270 mm).
In October 1927, the Soo's shops removed the H's bunker and tank in favor of a separate tender carrying 2,300 US gallons (8,705 litres) of water and 5 tons (4.5 metric tons) of coal. The tender weighed 53,100 lb (24,086 kg) loaded. It was placed with four other Ocean State-built 0-6-0s in class B.
But in June 1932, the Soo switched back to a tank locomotive layout and renumbered the 321 as class X-90. Chris Hohl pointed out that the reconfigured engine now carried 1,167 US gallons (4,417 litres) and 2.7 tons (2.5 metric tons.
In 1963, 76 years after it entered service on the MSSM&A, the X-90 was retired from the Soo, only to be sold to the Miller Compressing Company.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | H/B |
| Locobase ID | 16490 |
| Railroad | Minneapolis, Sault Ste Marie & Atlantic (Soo) |
| Country | USA |
| Whyte | 0-6-6T |
| Number in Class | 1 |
| Road Numbers | 38/321 |
| Gauge | Std |
| Number Built | 1 |
| Builder | Rhode Island |
| Year | 1887 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 10 / 3.05 |
| 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) | 90,700 / 41,141 |
| Engine Weight (lbs / kg) | |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | 1900 / 7.20 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 4 / 4 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 50 / 25 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 49 / 1245 |
| Boiler Pressure (psi / kPa) | 160 / 1100 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 18" x 24" / 457x610 |
| Tractive Effort (lbs / kg) | 21,582 / 9789.44 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.20 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 174 - 2" / 51 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 13.50 / 4.11 |
| Firebox Area (sq ft / m2) | 65.30 / 6.07 |
| Grate Area (sq ft / m2) | 15.69 / 1.46 |
| Evaporative Heating Surface (sq ft / m2) | 1296 / 120.40 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1296 / 120.40 |
| Evaporative Heating Surface/Cylinder Volume | 183.31 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2510 |
| Same as above plus superheater percentage | 2510 |
| Same as above but substitute firebox area for grate area | 10,448 |
| Power L1 | 2999 |
| Power MT | 218.69 |