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).
Results of tests comparing different 12-volt light bulbs.
| Identifier | ExFiles\Box 61a\1\ scan0012 | |
| Date | 19th October 1914 | |
| Wor{Arthur Wormald - General Works Manager}/Hy{Tom Haldenby - Plant Engineer}31/L191014. Sheet 2. tests when comparing the results. I do not claim great accuracy as our apparatus was very crude but the results are quite good enough for comparison. The standard of light was 10 feet from the screen in each case. All bulbs were 12 volts and the current taken by each kind was as follows :- No.11 C.A.V. (Ediswan) 1.8 amperes. No.13 C.A.V. (Ediswan) 2.6 " 24 C.P. Lucas (Osram) 1.75 " In some instances it will be noticed that the small lamp shows up better than the big lamp but it should be remembered that the big lamp has a wider field. Contd. | ||