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).
Graph charting electrical discharge performance over time.
| Identifier | ExFiles\Box 168b\3\ img174 | |
| Date | 29th August 1928 | |
| 29-8-28 185-6 P&R BDHII-3-4 107 cls 75 a.h. J/231 Average amperes = 6.23 Hours = 11.4 Ampere hours = 71 .664 1.80w | ||