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).
Electrical experimental record sheet tracking battery usage and mileage.
| Identifier | ExFiles\Box 168b\3\ img173 | |
| Date | 13th May 1928 | |
| 87535P 1 X No 7535 ELECTRICAL EXPERIMENTAL RECORD SHEETS. R&R 2-6 RR 11-3 Batt (190) Date on. | Location. | Date off. | REMARKS. | Miles Reading Start. | Miles Reading Finish. | Miles over Sd. | Total Miles. 10-2-28 | Sale | | Received charged 19-3-28 | 16 EX | 2-4-28 | | 147 | 172 | 26 | 26 2-4-28 | " | 13-5-28 | Battery gone with car. | 173 | 206 | 33 | 59 13-5-28 | " | ||