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).
Comparison of the Hele Shaw system against the Lentz system and ordinary mechanical change gear.
| Identifier | ExFiles\Box 136\4\ scan0014 | |
| Date | 23th October 1923 | |
| (2) The Hele Shaw system would give all the above good points and would not be liable to develop leakage trouble in use anything like as quickly or of such large dimensions as the Lentz system, but so far as I am aware even the Hele Shaw system has not proved itself as reliable as the ordinary mechanical change gear | ||