The temperature on June 17, 1915 was between 6.3 °C and 18.9 °C and averaged 12.7 °C. There was 9.2 hours of sunshine (55%). The average windspeed was 3 Bft (moderate breeze) and was prevailing from the north. Source: KNMI
In The Netherlands , there was from August 29, 1913 to September 9, 1918 the cabinet Cort van der Linden, with Mr. P.W.A. Cort van der Linden (liberaal) as prime minister.
January 19 » Georges Claude patents the neon discharge tube for use in advertising.
January 26 » The Rocky Mountain National Park is established by an act of the U.S. Congress.
January 28 » An act of the U.S. Congress creates the United States Coast Guard as a branch of the United States Armed Forces.
February 22 » World War I: The Imperial German Navy institutes unrestricted submarine warfare.
July 1 » Leutnant Kurt Wintgens of the then-named German Deutsches Heer's Fliegertruppe army air service achieves the first known aerial victory with a synchronized machine-gun armed fighter plane, the Fokker M.5K/MG Eindecker.
December 20 » World War I: The last Australian troops are evacuated from Gallipoli.
Day of marriage May 18, 1940
The temperature on May 18, 1940 was between 8.5 °C and 19.2 °C and averaged 13.4 °C. There was 9.9 hours of sunshine (63%). The average windspeed was 3 Bft (moderate breeze) and was prevailing from the north-northeast. Source: KNMI
In The Netherlands , there was from August 10, 1939 to September 3, 1940 the cabinet De Geer II, with Jonkheer mr. D.J. de Geer (CHU) as prime minister.
In The Netherlands , there was from September 3, 1940 to July 27, 1941 the cabinet Gerbrandy I, with Prof. dr. P.S. Gerbrandy (ARP) as prime minister.
May 15 » USSSailfish is recommissioned. It was originally the USS Squalus.
June 3 » Franz Rademacher proposes plans to make Madagascar the "Jewish homeland", an idea that had first been considered by 19th century journalist Theodor Herzl.
June 7 » King Haakon VII, Crown Prince Olav and the Norwegian government leave Tromsø and go into exile in London. They return exactly five years later.
August 8 » The "Aufbau Ost" directive is signed by Wilhelm Keitel.
August 25 » World War II: The first Bombing of Berlin by the British Royal Air Force.
September 27 » World War II: The Tripartite Pact is signed in Berlin by Germany, Japan and Italy.
When copying data from this family tree, please include a reference to the origin: Hans Weening, "Family tree Weening", database, Genealogy Online (https://www.genealogieonline.nl/stamboom-weening/I119559.php : accessed October 20, 2026), "Wybren Sikkema (1915-)".
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