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).
Performance chart showing the daily error of Smith Motor Type Electric Clocks on car 9 B V over approximately 65 days.
| Identifier | ExFiles\Box 164\1\ img256 | |
| Date | 6th January 1941 guessed | |
| SMITH MOTOR TYPE ELECTRIC CLOCKS ON CAR 9 B V MINS ERROR PER DAY DAYS 440 MILES RUN DAY VOLTS LOW STANDING BATT CHARGED 270 MILES 8K RUNNING 217 MILES 12.2V STANDING RUNNING 500 MILES RUN DAY & NIGHT VOLTS NOT OVER 11.9V CAR RUNNING BATT VOLTS LOW STANDING IN SHOP OFTEN 11.6V STANDING 1 DAY 192 MILES RUNNING DAY INSP. LAMP USED FOR SOME HOURS 42 MILES 150 MILES DAY & NIGHT RUNNING DAY & NIGHT 190 MILES DAY & NIGHT RUNNING NIGHT & DAY 95 MILES VOLTS LOW STANDING VOLTS NOT ABOVE 12 WHILE STANDING AFTER THIS DATE VOLTS ARE JUST OVER 13 NIGHT AND ABOUT 15.5 DAY RUNNING | ||