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).
Record concerning Sphinx plugs with 'R.R.' printed on them.
| Identifier | ExFiles\Box 79\2\ scan0166 | |
| Date | 23th July 1912 | |
| Section 1700 X/026 Description: Sphinx plugs. with R.R. printed on. Date: 23/7/12, Report: 6 of above handed to Howes to test. Sheet in abeyance file 'P'. Date: 3/8/12, Report: Testing Date: 25-9-12, Report: Testing | ||