On Wed 2021-09-08T18:54:03-0700 Tom Van Baak hath writ: > I am considering a below ground "clock room" away from the house. This will > be for some low-drift quartz oscillators and also a couple of precision > pendulum clocks. The goal is long-term, unattended, and very undisturbed > operation.
How deep? Bulletin Horaire v3n46p262 (1929-02-10) reports the equipment, facilities, and operations of Bureau International de l'Heure at Observatoire de Paris. The highest precision pendulum clocks, the ones which had mechanisms to correct for temperature and pressure (the "garde-temps") were kept 27 m below ground in caves and galleries which were part of the Paris catacombs. Various issues of Bulletin Horaire report discontinuities in the operation of those clocks due to distant earthquakes. -- Steve Allen <[email protected]> WGS-84 (GPS) UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855 1156 High Street Voice: +1 831 459 3046 Lng -122.06015 Santa Cruz, CA 95064 https://www.ucolick.org/~sla/ Hgt +250 m _______________________________________________ time-nuts mailing list -- [email protected] -- To unsubscribe send an email to [email protected] To unsubscribe, go to and follow the instructions there.
