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).
Graph comparing the performance of different brands of oil reconditioners over time.
| Identifier | ExFiles\Box 135\3\ scan0256 | |
| Date | 11th March 1938 | |
| OIL RECONDITIONER TESTS LUBER-FINER, GENERAL, A.C. AND SMITH DELIVERY TIME TESTS USED OIL - 75°C PRESSURE - 30 Lb/in² BY-PASS DELIVERY PTS. HR. TESTING TIME - HRS. 'A.C.' AND 'LUBER-FINER' A.C. 1st TEST INITIAL PURITY 48% 'LUBER-FINER' INITIAL PURITY 47% A.C. 2nd TEST INITIAL PURITY 23% 'GENERAL' 'GENERAL' 2ND TEST INITIAL PURITY 27% 'GENERAL' 1ST TEST INITIAL PURITY 55% 'SMITH' 'SMITH' 1ST TEST INITIAL PURITY 44% 'SMITH' 2ND TEST INITIAL PURITY 44% | ||