I've started to monitor the individual ticks on a grandfather clock from the 1790s. Essentially I timestamp whenever the pendulum breaks/restores a light beam.
The data that I get is surprising in that the pendulum swing varies according to the position of the hands on the clock. It appears that the amplitude of the swing depends on the driving force imparted by the escapement. Since the second hand is not counterweighted, there is slightly more energy available to drive the escapement during the first half of each minute and slightly less in the second half. There is much bigger effect at the end of each hour when the mechanism has to move a lever to trigger the strike mechanism. This 'end of hour' effect changes the pendulum swing enough so that the period is noticeably affected (maybe by 300ppm) Anyway, my google-fu did not reveal anybody else interested in this stuff... Anybody here interested? Philip _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
