A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Paul Hirose
Date: 2023 Nov 17, 10:58 -0800
It's well known that combat in the First World War ended at the 11th hour of the 11th day of the 11th month of 1918. But what time zone?
Greenwich Civil Time, says this December 1918 article in the English magazine "The Observatory". (GMT in that era was 12 hours behind GCT.)
articles.adabs.harvard.edu -- link
The center of gravity of France looks closer to the prime meridian than the 15th meridian.
But the Nautical Almanac says standard time in France is now UTC+1. So each year when the clocks are advanced to UTC+2,
French time approximates the "double summer time" of 1940s Britain.