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).
Feasibility of using 57 grooves in a car dynamo's armature.
| Identifier | ExFiles\Box 165\6\ img080 | |
| Date | 16th May 1927 | |
| To R.{Sir Henry Royce} from EFC. c. BJ. 5661 X-8664 EFC5/T16.5.27. RE CAR DYNAMO. In reply to your R10/M29.4.27, it does not appear practicable to adopt 57 grooves in the armature. EFC. | ||