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 plotting ball pin load against external pressure for a leather piston type at various RPMs.
| Identifier | ExFiles\Box 179b\2\ img209 | |
| Date | 14th December 1932 | |
| BRITISH MADE J III REAR 40/40 LB NS{Norman Scott} 3497 LEATHER PISTON TYPE HS{Lord Ernest Hives - Chair} 795 14.12.32. 1st STROKE BALL PIN LOAD LB 300 200 100 EXTERNAL PRESS. LB/D' 5 10 15 20 540 R.P.M. 360 R.P.M. 180 R.P.M. 90 R.P.M. CUP LEATHER | ||