On Wed 2019-03-27T16:26:09+1300 Bruce Griffiths hath writ: > The Danjon impersonal astrolabe is perhaps better suited to accurate > measurements: > https://www.nzmuseums.co.nz/collections/3267/objects/3380/astrolabe
Danjon became director of Observatoire de Paris (and thus also the BIH) in 1945. In 1948 the ITU realized that it could not make reasonable regulations about frequency in the absence of an expert on timing, so ITU requested the IAU send a representative to Study Group 7, and Danjon was that representative. Danjon was head of the CCDS from inception into the late 1960s. The raw data about the clocks at Observatoire de Paris (which were located in the catacombs for temperature stability) from the 1920s into the quartz era are almost all published in Bulletin Horaire. The early issues are all scanned and online at Harvard ADS. That is a huge amount data on earth disciplined oscillators, a treasure chest of descriptions and diagrams of early circuits and drum recording devices, and a pile of dirty laundry about who made good and bad decisions in international agreements about time. -- 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, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
