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 chart recording the results of a component test, including average amperes, hours, and ampere-hours.
| Identifier | ExFiles\Box 58\3\ Scan194 | |
| Date | 18th March 1930 | |
| 18-3-30 211/2 Exide 3RR5-TEL-3·4 75 a.h. 110 lbs Average amperes = 6·19 Hours = 11·5 Ampere Hours = 71·1 ·646 1·80w EVERETT, EDGCUMBE & CO., LTD., LONDON. | ||