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).
Introduction of a special non-reversible plug for the Lucas switch box for inspection lamps or external charging.
| Identifier | ExFiles\Box 40\2\ Scan016 | |
| Date | 11th March 1920 | |
| X.3552 To Em. From Ck.{Mr Clark} c. to Dn. c. to Ry. c. to Ez. ---------------- RE X.3749. LUCAS SWITCH BOX. X.3552 Inspection Lamp, or External Charging plug and Socket. We take it from Mr. Royce's note R19/CS.3.20, that he would be agreeable on our Lucas standard switchbox to the use of the special plug which cannot be put in the wrong direction. If you consider this meets the case perhaps you will kindly arrange with Production for such a plug to be supplied with every box. This does not involve any alteration to the box except that we are already asking for the two sockets to be marked + and - . We attach copy of Mr. Royce's note to By's copy of the present memo. Ck.{Mr Clark} | ||