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.
February 22 » World War I: The Imperial German Navy institutes unrestricted submarine warfare.
April 5 » Boxing challenger Jess Willard knocks out Jack Johnson in Havana, Cuba to become the Heavyweight Champion of the World.
April 18 » French pilot Roland Garros is shot down and glides to a landing on the German side of the lines during World War I.
May 6 » Babe Ruth, then a pitcher for the Boston Red Sox, hits his first major league home run.
August 6 » World War I: Battle of Sari Bair: The Allies mount a diversionary attack timed to coincide with a major Allied landing of reinforcements at Suvla Bay.
August 29 » US Navy salvage divers raise F-4, the first U.S. submarine sunk in an accident.
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.
February 27 » Martin Kamen and Sam Ruben discover carbon-14.
March 5 » Six high-ranking members of Soviet politburo, including Joseph Stalin, sign an order for the execution of 25,700 Polish intelligentsia, including 14,700 Polish POWs, in what will become known as the Katyn massacre.
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.
June 22 » World War II: France is forced to sign the Second Compiègne armistice with Germany, in the same railroad car in which the Germans signed the Armistice in 1918.
November 9 » Warsaw is awarded the Virtuti Militari.
November 16 » World War II: In response to the leveling of Coventry by the German Luftwaffe two days before, the Royal Air Force bombs Hamburg.
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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