February 1 » La bohème premieres in Turin at the Teatro Regio (Turin), conducted by the young Arturo Toscanini.
May 26 » Charles Dow publishes the first edition of the Dow Jones Industrial Average.
June 2 » Guglielmo Marconi applies for a patent for his wireless telegraph.
June 4 » Henry Ford completes the Ford Quadricycle, his first gasoline-powered automobile, and gives it a successful test run.
September 22 » Queen Victoria surpasses her grandfather King George III as the longest reigning monarch in British history.
December 30 » Canadian ice hockey player Ernie McLea scores the first hat-trick in Stanley Cup play, and the Cup-winning goal as the Montreal Victorias defeat the Winnipeg Victorias 6–5.
Day of marriage November 19, 1931
The temperature on November 19, 1931 was between 2.1 °C and 4.8 °C and averaged 3.7 °C. The average windspeed was 4 Bft (moderate breeze) and was prevailing from the south east. Source: KNMI
In The Netherlands , there was from August 10, 1929 to May 26, 1933 the cabinet Ruys de Beerenbrouck III, with Jonkheer mr. Ch.J.M. Ruys de Beerenbrouck (RKSP) as prime minister.
February 3 » The Hawke's Bay earthquake, New Zealand's worst natural disaster, kills 258.
February 13 » The British Raj completes its transfer from Calcutta to New Delhi.
February 20 » The U.S. Congress approves the construction of the San Francisco–Oakland Bay Bridge by the state of California.
March 11 » Ready for Labour and Defence of the USSR, abbreviated as GTO, is introduced in the Soviet Union.
March 26 » Swissair is founded as the national airline of Switzerland.
October 21 » A secret society in the Imperial Japanese Army launches an abortive coup d'état attempt.
Day of death June 13, 1951
The temperature on June 13, 1951 was between 13.2 °C and 18.4 °C and averaged 15.4 °C. There was 0.1 mm of rain during 0.1 hours. There was 4.0 hours of sunshine (24%). The heavily clouded was. The average windspeed was 4 Bft (moderate breeze) and was prevailing from the west-southwest. Source: KNMI
From August 7, 1948 till March 15, 1951 the Netherlands had a cabinet Drees - Van Schaik with the prime ministers Dr. W. Drees (PvdA) and Mr. J.R.H. van Schaik (KVP).
In The Netherlands , there was from March 15, 1951 to September 2, 1952 the cabinet Drees I, with Dr. W. Drees (PvdA) as prime minister.
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/I77559.php : accessed February 12, 2026), "Roelf de Groot (1896-1951)".
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