Data from "The First 'Mallet' Compound Locomotives," The Locomotive Magazine, Vol VIII (6 June 1903), p. 395-396. Anatole Mallet, Etude sur L'Utilisation de la Vapeur dans les Locomotives et L'Application a ces Machines du Fonctionnement Compound (Paris: Librairie Polytechnique Ch. Beranger, Ed, 1878), especially pp. 126-131.
Mallet's second class of compound locomotives adopted a very different ratio between the high and low-pressure cylinders. Significantly less than 2, the figure indicated an LP cylinder too small to make full use of the steam from the HP cylinder. It wouldn't before Mallet would work out the proportions; see Locobase 11175.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Dax |
| Locobase ID | 10334 |
| Railroad | Bayonne-Anglet-Biarritz |
| Country | France |
| Whyte | 0-6-0T |
| Number in Class | 2 |
| Road Numbers | |
| Gauge | Std |
| Number Built | 2 |
| Builder | Schneider-Creusot |
| Year | 1878 |
| Valve Gear | |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 8.86 / 2.70 |
| Engine Wheelbase (ft / m) | 8.86 / 2.70 |
| Ratio of driving wheelbase to overall engine wheelbase | 1 |
| Overall Wheelbase (engine & tender) (ft / m) | 8.86 / 2.70 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 52,911 / 24,000 |
| Engine Weight (lbs / kg) | 52,911 / 24,000 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | 52,911 / 24,000 |
| Tender Water Capacity (gals / ML) | 660 / 2.50 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 29 / 14.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 47.20 / 1200 |
| Boiler Pressure (psi / kPa) | 140.70 / 970 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 11.02" x 21.65" / 305x550 (1) |
| Low Pressure Cylinders (dia x stroke) (in / mm) | 16.54" x 21.65" / 420x550 (1) |
| Tractive Effort (lbs / kg) | 4614 / 2092.88 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 11.47 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 130 - 1.772" / 45 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 9.51 / 2.90 |
| Firebox Area (sq ft / m2) | 61.33 / 5.70 |
| Grate Area (sq ft / m2) | 13.56 / 1.26 |
| Evaporative Heating Surface (sq ft / m2) | 610 / 56.70 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 610 / 56.70 |
| Evaporative Heating Surface/Cylinder Volume | 510.46 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 1908 |
| Same as above plus superheater percentage | 1908 |
| Same as above but substitute firebox area for grate area | 8629 |
| Power L1 | 3769 |
| Power MT | 471.12 |