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).
Graph showing deflection versus load for various types of engine foot rubbers.
| Identifier | ExFiles\Box 65\4\ scan0116 | |
| Date | 4th December 1928 | |
| ENGINE FOOT RUBBERS. DEFLN 1/100 INS LOAD LBS. X. 20 H.P. BLOCK 1.250 LONG A.{Mr Adams} LAST BATCH 1 DOZ EXP RUBBERS 1.125" LONG B. STANDARD. 40/50 1.150 LONG C. REQUIRED RATING FOR RUBBERS 1.125 LONG D.{John DeLooze - Company Secretary} ULTRA STIFF RUBBERS REQD 1.050 LONG | ||