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).
Comparison of engine litre displacement metrics presented in two tables.
| Identifier | ExFiles\Box 24\4\ Scan116 | |
| Date | 10th December 1923 guessed | |
| E.{Mr Elliott - Chief Engineer} A.{Mr Adams} C. COMPARISON OF LITRE DISPLACEMENT. First Table: Column 1: Area of matrix face per litre displ: 66.0 sq in. Column 2: Surface of core per litre displ: 16.8 sq ft. Column 3: Surface of core per litre displ: per inch. of depth: 4.2 sq. in. COMPARISON ON 1000 LITRE DISPLACEMENT PER MILE ON DIRECT DRIVE BASIS. Second Table: Column 1: Area of matrix face per 1000 ltr. displ: per mile: 61.7 sq.in. Column 2: Surface of core per 1000 ltrs. displ: per mile: 15.72 sq.ft. Column 3: Surface of core per in. of depth per 1000 ltr. displ: per mile: 3.93 sq.ft. | ||