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).
Chart recording from a 'Megger' recorder showing an electrical test, possibly a battery discharge, with handwritten calculations.
| Identifier | ExFiles\Box 54\1\ Scan168 | |
| Date | 10th November 1926 | |
| 10-11-26 182 P&R RRII-3 97 lbs 75 a.h. Average amperes - 6.21a Hours - 10.6 Ampere hours - 66.0 680 1.80w TRADE MARK "MEGGER" RECORDER | ||