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).
Calculation of vehicle weight and fuel efficiency for a 250-mile trip to Wales.
| Identifier | ExFiles\Box 147\5\ scan0030 | |
| Date | 17th June 1909 guessed | |
| 60552 - Mr Royce weekend in Wales 250 miles 3800 (2300) X459 . 5 passengers. 200lbs. luggage. (50lbs extra tyres) Geared 24. Grey test body & mudguards & footboards etc. (low for road) say. 5 cwt. Total = 26 . 0 . 8. + 5 pass + 250 lbs. = 3948 lbs. at 20 miles per gall. = 35. ton miles per gall. | ||