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).
Observations and diagrams of electrical spark and arc characteristics under different conditions.
| Identifier | ExFiles\Box 63\4\ scan0008 | |
| Date | 26th May 1918 guessed | |
| (25) ZR6/2000/2/A/A Sparkys Striations. Dots of light. (26) ZR6/2000/2/A/B Same general remarks as for 600 R.P.M. (27) ZR6/2000/2/R/A Arc at retard wore bushy " " " " Flamey. " " " " yellowish. (applies also to 5 & 7mm. gap) (28) ZR6/2000/2/R/B Ditto. (29) ZR6/2000/5/A/A Arc at advance more mauvish more striation effect harder outline. Applies also to 2½ & 7mm. gap. (30) ZR6/2000/5/A/B Ditto. | ||