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).
Trial and potential standardisation of Zenith filters on a 20 HP car.
| Identifier | ExFiles\Box 44\1\ Scan129 | |
| Date | 9th March 1927 | |
| Mm. from Hs.{Lord Ernest Hives - Chair} c. to Wor.{Arthur Wormald - General Works Manager} c. to BY.{R.W. Bailey - Chief Engineer} X3700 Hsl/LG9.3.27. ZENITH FILTERS. In our opinion the Zenith filter is an improvement over our present standard filter. We have fitted a Zenith filter on the 20 HP. car which is to run 10,000 miles with the object of standardising it. There is no technical objection to fitting Zenith filters. Hs.{Lord Ernest Hives - Chair} | ||