Mark Adlington in the Quarry Engines of North Wales website -- pws.prserv.net/mdsme/Hunslet/Alice_class.htm -- gives us the dimensions for what may forever be the smallest locomotive in Locobase. Louisa was one of the first Hunslet engines to work the Penrhyn Quarries; George joined later.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Louisa |
| Locobase ID | 5986 |
| Railroad | Lower Glynrhonwy Quarry, Llanberis |
| Country | Great Britain |
| Whyte | 0-4-0ST |
| Number in Class | 2 |
| Road Numbers | |
| Gauge | 60 cm |
| Number Built | 2 |
| Builder | Hunslet Engine Co |
| Year | 1877 |
| Valve Gear | |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 2.99 / 0.91 |
| Engine Wheelbase (ft / m) | 2.99 / 0.91 |
| Ratio of driving wheelbase to overall engine wheelbase | 1 |
| Overall Wheelbase (engine & tender) (ft / m) | |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 8737 / 3963 |
| Engine Weight (lbs / kg) | 8737 / 3963 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | |
| Tender Water Capacity (gals / ML) | 71 / 0.27 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 7 / 3.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 18 / 457 |
| Boiler Pressure (psi / kPa) | 140.70 / 970 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 5" x 8" / 127x203 |
| Tractive Effort (lbs / kg) | 1329 / 602.82 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 6.57 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | |
| Firebox Area (sq ft / m2) | |
| Grate Area (sq ft / m2) | 1.72 / 0.16 |
| Evaporative Heating Surface (sq ft / m2) | 56 / 5.20 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 56 / 5.20 |
| Evaporative Heating Surface/Cylinder Volume | 308.02 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 242 |
| Same as above plus superheater percentage | 242 |
| Same as above but substitute firebox area for grate area | |
| Power L1 | |
| Power MT | |