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).
Reporting a cracked porcelain on a Mercury plug after testing in a Goshawk engine.
| Identifier | ExFiles\Box 50\2\ Scan047 | |
| Date | 8th March 1921 | |
| XH295 Mr. Hives. 8.3.21. MERCURY PLUGS. Herewith Mercury plug - please note porcelain cracked after running 682 miles in Goshawk engine. GWH.{George W. Hancock - Head Chateauroux} | ||