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).
Performance graph with a dual-scaled Y-axis for M.E.P. (Lbs. Per Sq. Inch) and Ft Lbs.
| Identifier | Morton\M7\ img065 | |
| Date | 5th May 1921 guessed | |
| & M.E.P. (LBS. PER SQ. INCH.) FT LBS: 100. 90. 80. 70. 60. 300 270 240 210 180 | ||