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).
Product sheet for a Hewittic Electric Company Limited Mercury Vapour Rectifier.
| Identifier | ExFiles\Box 32\5\ Scan008 | |
| Date | 21th September 1921 guessed | |
| X. 1589. MERCURY VAPOUR RECTIFIER Single bulb type, D.C. output up to 100 or 150 amperes HEWITTIC ELECTRIC COMPANY LIMITED, 80, YORK ROAD, KING'S CROSS, LONDON, N.1. | ||