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 the efficiency and deflection of a pin-jointed octagon under load.
| Identifier | ExFiles\Box 84\2\ scan0247 | |
| Date | 21th December 1934 guessed | |
| EFFICIENCY (95.5%) % EFFICIENCY DEFLECTION THOUSANDTHS OF AN INCH LBS INPUT EFFICIENCY OF PIN JOINTED OCTAGON R R PIN JOINTS NºS G.53634, G.50142, G.52047. SPRING BALANCE IN ONE "SECONDARY" SIDE GIVING DEFINITE SLIP IN JOINTS FOR N = 95.5% M = 0.265 | ||