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 mileage performance of various samples of bone grey fibre rubbing blocks.
| Identifier | ExFiles\Box 69\1\ scan0374 | |
| Date | 18th May 1925 | |
| X.4646 EFC. 18.5.25. X.4646. MILEAGES TO DATE OF BONE GREY FIBRE RUBBING BLOCKS. 2nd Sample No.2E - 8684 miles (8-GII). " " " 2D - 9220 " (5-EX). " " " T₂ - Considerably over 10,000 miles (93-NK). 1st sample No.- 8696 miles (6-GII). EFC/HEW. | ||