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).
Test results for a spring clip's average life before breakage.
| Identifier | ExFiles\Box 29\4\ Scan003 | |
| Date | 17th September 1914 guessed | |
| Wor{Arthur Wormald - General Works Manager}/Mcr14/L11514. Sheet. 3 Piece No. | Description. | Time Hrs. Mins | Results. | Reference K.5400 | Spring clip, off side. | 4 - 29 | Broke. | Wor{Arthur Wormald - General Works Manager}/Hy{Tom Haldenby - Plant Engineer}18/L17214 Average Life before breakage K5400. Spring Clip, near side. | 4 hrs 25 mins. | Average over 19 K.5400. Spring clip, off side. | 4 " 11 | " " 13 | ||