Data from "Narrow-Gauge Locomotive, Southern Nigeria Railways", The Locomotive, Volume XVI (15 February 1910), p. 36. See also Shehu Tijani Yusuf, The Socio-Economic Impact of the Railway in Northern Nigeria, Chapter 2 of a dissertation submitted to Leiden University (2015, January 20). Works numbers were 879-880 for the Baro-Kano, 881-886 for Southern Nigerian.
This set of metre-gauge Prairies had Belpaire fireboxes and large cabs. The latter were much wider at seat height than at footboard level. LM attributed the engines' design to the railways' consulting engineers, Messrs Elliot, Cooper & Shelford.
As shown in the works numbers information, the first two locomotives went directly to the Baro-Kano, a Northern Nigeria railway begun in 1908 to connect the port of Baro to Kano in the interior.It was the brainchild of Frederick Lugard, the NN's High Commissioner who felt keenly the NN's ability to compete with the Lagos Railway. Lugard explained his pursuit of a railway succinctly, as Shehu Iijani Yusuf reports: "the material development of Africa may be summed up in one word---Transport."
It can be argued that Lugard's efforts had an effect, as the NN merged with the Lagos Railway in 1912 to form Nigerian Railways.
Data from "Engine Nos 41-42", Diagram drafted September 1949 at Ebutemetta. (Thanks to Teemu Koivumaki for finding this diagram and emailing it to me on 29 August 2024.) Works numbers were 2849-2850 in January 1948.
Compared to the 2-6-2 Prairie engines delivered to the Baro-Kano 38 years earlier (Locobase 16043), these tanks had higher-pressure boilers and more heating surface area. Consequently, they displayed more power.
Principal Dimensions by Steve Llanso of Middle Run Media | ||
---|---|---|
Class | 13, 201 | 41 |
Locobase ID | 16043 | 21198 |
Railroad | Southern Nigeria | Southern Nigeria |
Country | Nigeria | Nigeria |
Whyte | 2-6-2 | 2-6-2T |
Number in Class | 8 | 2 |
Road Numbers | 13-14, 201-206 | 41-42 |
Gauge | 3'6" | 3'6" |
Number Built | 8 | 2 |
Builder | Nasmyth Wilson | Nasmyth Wilson |
Year | 1909 | 1948 |
Valve Gear | Stephenson | Stephenson |
Locomotive Length and Weight | ||
Driver Wheelbase (ft / m) | 10.50 / 3.20 | 10 / 3.05 |
Engine Wheelbase (ft / m) | 21.50 / 6.55 | 24 / 7.32 |
Ratio of driving wheelbase to overall engine wheelbase | 0.49 | 0.42 |
Overall Wheelbase (engine & tender) (ft / m) | 24 / 7.32 | |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | 24,940 / 11,313 | |
Weight on Drivers (lbs / kg) | 73,920 / 33,530 | |
Engine Weight (lbs / kg) | 86,128 / 39,067 | 105,840 / 48,008 |
Tender Loaded Weight (lbs / kg) | 30,016 / 13,615 | 30,016 / 13,615 |
Total Engine and Tender Weight (lbs / kg) | 116,144 / 52,682 | 135,856 / 61,623 |
Tender Water Capacity (gals / ML) | 2400 / 9.09 | 960 / 3.64 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 2.85 / 2.60 | |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 41 / 20.50 | |
Geometry Relating to Tractive Effort | ||
Driver Diameter (in / mm) | 48 / 1219 | 42.75 / 1086 |
Boiler Pressure (psi / kPa) | 150 / 1030 | 180 / 1240 |
High Pressure Cylinders (dia x stroke) (in / mm) | 15" x 20" / 381x508 | 15" x 20" / 381x508 |
Tractive Effort (lbs / kg) | 11,953 / 5421.80 | 16,105 / 7305.11 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.59 | |
Heating Ability | ||
Tubes (number - dia) (in / mm) | 192 - 1.75" / 44 | 192 - 1.75" / 44 |
Flues (number - dia) (in / mm) | ||
Flue/Tube length (ft / m) | 9.83 / 3 | 9.83 / 3 |
Firebox Area (sq ft / m2) | 93 / 8.64 | 98 / 9.10 |
Grate Area (sq ft / m2) | 14 / 1.30 | 14 / 1.30 |
Evaporative Heating Surface (sq ft / m2) | 987 / 91.69 | 1024 / 95.13 |
Superheating Surface (sq ft / m2) | ||
Combined Heating Surface (sq ft / m2) | 987 / 91.69 | 1024 / 95.13 |
Evaporative Heating Surface/Cylinder Volume | 241.28 | 250.33 |
Computations Relating to Power Output (More Information) | ||
Robert LeMassena's Power Computation | 2100 | 2520 |
Same as above plus superheater percentage | 2100 | 2520 |
Same as above but substitute firebox area for grate area | 13,950 | 17,640 |
Power L1 | 4260 | 4747 |
Power MT | 424.73 |