Data from Ahrons (1927). See also Clement E Stretton, "The New Express Engines Upon the Glasgow and South Western Railway," English Mechanic and World of Science, No. 819 (3 December 1880), p. 301.
A Hugh Smellie design that Glover (1967) comments deserve the palm for Scottish 2-4-0s, although he's not certain why they were called the "Apostles."
"Certainly, " says Glover, "-- like all of this designer's productions -- they were exemplary locomotives -- fast, powerful, and economical."
At the time of their introduction, Clement Stretton provided detailed support for a positive view of this design: "The distance from Glasgow to Cirlisle is 115 miles 36 chains, and from the working time-tables I find that 2h. 43m. is the time allowed to perform the journey, including 10 minutes' standing at Kil- maruock, and Dumfries stations.
"When the gradients are taken into consideration it will be seen that the work performed by the Glasgow and South-Western engines is very good indeed, and, if it were necessary, the journey could be accomplished in less time by them."
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Twelve Apostles |
| Locobase ID | 2996 |
| Railroad | Glasgow & South Western |
| Country | Great Britain |
| Whyte | 2-4-0 |
| Number in Class | 12 |
| Road Numbers | |
| Gauge | Std |
| Number Built | 12 |
| Builder | Kilmarnock |
| Year | 1879 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | |
| Engine Wheelbase (ft / m) | 16.25 |
| Ratio of driving wheelbase to overall engine wheelbase | |
| Overall Wheelbase (engine & tender) (ft / m) | |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 31,360 |
| Weight on Drivers (lbs / kg) | 65,184 / 29,567 |
| Engine Weight (lbs / kg) | 86,240 / 39,118 |
| Tender Loaded Weight (lbs / kg) | 61,824 / 28,043 |
| Total Engine and Tender Weight (lbs / kg) | 148,064 / 67,161 |
| Tender Water Capacity (gals / ML) | 2520 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 3.30 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 54 / 27 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 81.50 / 2070 |
| Boiler Pressure (psi / kPa) | 140 / 970 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 18" x 26" / 457x660 |
| Tractive Effort (lbs / kg) | 12,300 / 5579.19 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 5.30 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 240 - 1.625" / 41 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | |
| Firebox Area (sq ft / m2) | 101 / 9.39 |
| Grate Area (sq ft / m2) | 16 / 1.49 |
| Evaporative Heating Surface (sq ft / m2) | 1206 / 112.08 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1206 / 112.08 |
| Evaporative Heating Surface/Cylinder Volume | 157.49 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2240 |
| Same as above plus superheater percentage | 2240 |
| Same as above but substitute firebox area for grate area | 14,140 |
| Power L1 | 4249 |
| Power MT | 287.42 |