[tz] 1911 France change from Paris to GMT

[Steve Allen]

On Sat 2020-06-13T19:39:42-0700 Paul Eggert hath writ:
> I have my doubts that this sort of thing was routinely done by hand, because
> even back in 1911 it would have been more reliable to do it automatically.
> (Though perhaps it was done by hand on the 1911-03-11 transition, as the
> salaries could easily have been justified for that special case.)

Of course for this we are looking at the June/July transition.

> Although I haven't found sources for what practices were in place at the Eiffel
> Tower on March 10/11, 1911, I did find the following abstract on page 265 of
> Science Abstracts. Section B - Electrical Engineering. Vol. XIV. 1911. It
> suggests that an automatic relay was feasible at the Eiffel Tower in March 1911,
> as Norddeich was already doing that in 1910. And this source confirms that the
> Eiffel Tower was routinely broadcasting time signals near midnight by 1910.

Aha, wonderful.  That is pre-BIH, pre-International Time Conference,
so it will be whatever they had been doing locally at that date
without any international agreements and specifications.  Further
details require delving into the publications of Observatoire de
Paris.  Alas, our library is locked down due to COVID until further
notice, so the answer will have to wait a while.

--
Steve Allen                    <sla at ucolick.org>              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