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).
Letter to British Thompson Houston Co. Ltd. about headlamp bulbs, including a request for a double filament lamp and a yellow glass bulb for the French market.
| Identifier | ExFiles\Box 166\4\ img220 | |
| Date | 8th November 1938 | |
| 6089 EXPERIMENTAL DEPARTMENT. Rm{William Robotham - Chief Engineer}/RC.{R. Childs}10/WH. 8th. November, 1938. The British Thompson Houston Co.Ltd., RUGBY. For the attention of Mr. Edmundson. Dear Sirs, Further to our conversation over the 'phone re the lamp bulbs, the standard as used in our existing headlamp is a single filament bulb with a Lucas-Graves two pin cap, thus, if for the tests, you make a double filament lamp with the two pin Lucas-Graver type cap, we shall be alright. Provision has been made in the headlamp for focusing. We note, that in France, it will be compulsory to use bulbs with yellow glass, as from January 1939. We have obtained one of these in France named 'Yvel granita' which gives good results in the Lucas FT.67 centre lamp. Do you manufacture this type of bulb? If so, will you please send me particulars, and if possible, a sample for trial. Yours faithfully, FOR ROLLS-ROYCE LTD. | ||