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).
Summary table of Telegauge failures over a six-month period, including remarks on reliability.
| Identifier | ExFiles\Box 47\3\ Scan207 | |
| Date | 21th September 1931 guessed | |
| 20 HP. 25 HP. PH.I. PH.II. TOTAL. GRAND TOTAL. REMARKS. TELEGAUGE FAILURES. June Quarter. C.C. 1 18 1 39 59 } 65 W.P. - 2 - 4 6 } Previous " C.C. 2 22 - 22 46 } 59 W.P. 1 3 - 9 13 } Six months. 4 45 1 74 124 124 Generally speaking, these instruments are not too reliable and further investigation is required. | ||