From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Cost comparison for Leyland and Wraith gearboxes, detailing weight, material, and labour costs.
| Identifier | ExFiles\Box 148\2\ scan0141 | |
| Date | 17th March 1939 | |
| -2- 17.3.39. Cost GEARBOX. Mat. Lab. Leyland 130 lbs. £9/7/- £3/13/6 Wraith 90 lbs. £9/19/8 £11/8/2 Leyland Mat. 187/- Wraith 199.7/- 228.2/- Lab. 73.5/- Cost/lb. Mat. Lab. 187 / 130 = 1.44 .566 199.7 / 90 = 2.2 2.54 Rm. {William Robotham - Chief Engineer} | ||