Data from "Locomotives of the Great Eastern", Locomotive Magazine, Volume 17 (15 April 1911) p. 76. Works numbers were 298-299 in 1870.
The T&W opened on 18 October 1869 from the Great Eastern's Roudham Junction 18 1/2 miles (29.8 km) west to Watton. This pair of small, but serviceable tanks represented the first specially ordered motive power.
The T&W would also run the Watton & Swaffham, which ran nine miles north over a long artificial embankment to Swaffham. Both were leased to the Great Eastern in 1879 and the two engines were renumbered 802-803 and renumbered 0802-0803 in 1886.
The 0802 was scrapped in October 1887 with 0803 following in May 1888.
Data from "Locomotives of the Great Eastern", Locomotive Magazine, Volume 17 (15 May 1911) p. 99. Works numbers were 2474-2475 in 1875.
20040 shows the first pair of four-coupled tanks delivered to the T&W. This pair, which arrived five years later, had taller drivers for more speed and more cylinder volume to offset that drop in tractive effort.
They joined five other T&W engines as leased equipment to the Great Eastern in 1879, when they were renumbered 804-805. Renumbered 0804-0806 in 1886, both locomotives were scrapped in August 1887.
| Principal Dimensions by Steve Llanso of Middle Run Media | ||
|---|---|---|
| Class | 2 | 4 |
| Locobase ID | 20040 | 20041 |
| Railroad | Thetford & Watton | Thetford & Watton |
| Country | Great Britain | Great Britain |
| Whyte | 2-4-0T | 2-4-0T |
| Number in Class | 2 | 2 |
| Road Numbers | 2-3/802-803/0802-0803 | 4-5/804-805/0804-0805 |
| Gauge | Std | Std |
| Number Built | 2 | 2 |
| Builder | Manning Wardle | Sharp, Stewart |
| Year | 1870 | 1875 |
| Valve Gear | Stephenson | |
| Locomotive Length and Weight | ||
| Driver Wheelbase (ft / m) | 5.67 / 1.73 | 6.25 / 1.90 |
| Engine Wheelbase (ft / m) | 11 / 3.35 | 12.25 / 3.73 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.52 | 0.51 |
| Overall Wheelbase (engine & tender) (ft / m) | 11 / 3.35 | 12.25 / 3.73 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 21,420 / 9716 | 24,024 / 10,897 |
| Weight on Drivers (lbs / kg) | 43,092 / 19,546 | 47,152 / 21,388 |
| Engine Weight (lbs / kg) | 59,724 / 27,090 | 65,996 / 29,935 |
| Tender Loaded Weight (lbs / kg) | ||
| Total Engine and Tender Weight (lbs / kg) | ||
| Tender Water Capacity (gals / ML) | 840 / 3.18 | 720 / 2.73 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 1.10 / 1 | 1.10 / 1 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 36 / 18 | 39 / 19.50 |
| Geometry Relating to Tractive Effort | ||
| Driver Diameter (in / mm) | 42 / 1067 | 48 / 1219 |
| Boiler Pressure (psi / kPa) | 120 / 830 | 120 / 830 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 13" x 20" / 330x508 | 15" x 20" / 381x508 |
| Tractive Effort (lbs / kg) | 8209 / 3723.54 | 9563 / 4337.71 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 5.25 | 4.93 |
| Heating Ability | ||
| Tubes (number - dia) (in / mm) | 109 - 2" / 51 | 170 - 1.75" / 44 |
| Flues (number - dia) (in / mm) | ||
| Flue/Tube length (ft / m) | 9.25 / 2.82 | 9.25 / 2.82 |
| Firebox Area (sq ft / m2) | 52.50 / 4.88 | 60.30 / 5.60 |
| Grate Area (sq ft / m2) | 10.50 / 0.98 | |
| Evaporative Heating Surface (sq ft / m2) | 578 / 53.70 | 781 / 72.56 |
| Superheating Surface (sq ft / m2) | ||
| Combined Heating Surface (sq ft / m2) | 578 / 53.70 | 781 / 72.56 |
| Evaporative Heating Surface/Cylinder Volume | 188.12 | 190.92 |
| Computations Relating to Power Output (More Information) | ||
| Robert LeMassena's Power Computation | 1260 | |
| Same as above plus superheater percentage | 1260 | |
| Same as above but substitute firebox area for grate area | 6300 | 7236 |
| Power L1 | 2298 | 2540 |
| Power MT | 235.13 | 237.52 |