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).
The average life of frames before breakage.
| Identifier | ExFiles\Box 119\2\ scan0042 | |
| Date | 1st May 1914 | |
| Wor{Arthur Wormald - General Works Manager}/Mcr4/L15414. May 1st. 1914. Average Life before breakage. |---------------------------------------------------------------------| | F.1325/6. Frame. 3 hrs 30 mins. broken. Average over one | | F.2398. Frame. 5 " 13 " " " " three. | | F.3715. Frame. 7 " 55 " cracked. " " two | |---------------------------------------------------------------------| | ||