January 31 » Czechoslav Trade Union Association is founded in Prague.
April 18 » The Greco-Turkish War is declared between Greece and the Ottoman Empire.
July 2 » British-Italian engineer Guglielmo Marconi obtains a patent for radio in London.
July 11 » Salomon August Andrée leaves Spitsbergen to attempt to reach the North Pole by balloon. He later crashes and dies.
August 31 » Thomas Edison patents the Kinetoscope, the first movie projector.
September 12 » Tirah Campaign: In the Battle of Saragarhi, ten thousand Pashtun tribesmen suffer several hundred casualties while attacking 21 Sikh soldiers in British service.
Day of marriage April 30, 1921
The temperature on April 30, 1921 was between 6.8 °C and 20.2 °C and averaged 13.7 °C. There was 12.0 hours of sunshine (81%). The average windspeed was 3 Bft (moderate breeze) and was prevailing from the northeast. Source: KNMI
In The Netherlands , there was from September 9, 1918 to September 18, 1922 the cabinet Ruys de Beerenbrouck I, with Jonkheer mr. Ch.J.M. Ruys de Beerenbrouck (RKSP) as prime minister.
March 6 » Portuguese Communist Party is founded as the Portuguese Section of the Communist International.
May 8 » The creation of the Communist Party of Romania.
July 27 » Researchers at the University of Toronto, led by biochemist Frederick Banting, prove that the hormone insulin regulates blood sugar.
September 5 » Roscoe "Fatty" Arbuckle party in San Francisco ends with the death of the young actress Virginia Rappe: One of the first scandals of the Hollywood community.
October 19 » The Portuguese Prime Minister and several officials are murdered in the Bloody Night coup.
October 29 » United States: Second trial of Sacco and Vanzetti in Boston, Massachusetts.
Day of death September 2, 1980
The temperature on September 2, 1980 was between 7.3 °C and 20.5 °C and averaged 14.1 °C. There was -0.1 mm of rain. There was 10.5 hours of sunshine (77%). The partly clouded was. The average windspeed was 1 Bft (weak wind) and was prevailing from the south-southeast. Source: KNMI
In The Netherlands , there was from Monday, December 19, 1977 to Friday, September 11, 1981 the cabinet Van Agt I, with Mr. A.A.M. van Agt (CDA/KVP) as prime minister.
January 29 » The Rubik's Cube makes its international debut at the Ideal Toy Corp. in Earl's Court, London.
February 26 » Egypt and Israel establish full diplomatic relations.
May 9 » In Florida, Liberian freighter MVSummit Venture collides with the Sunshine Skyway Bridge over Tampa Bay, making a 1,400-ft. section of the southbound span collapse. Thirty-five people in six cars and a Greyhound bus fall 150ft. into the water and die.
August 1 » A train crash kills 18 people in County Cork, Ireland.
November 23 » The 6.9 Mw Irpinia earthquake shakes southern Italy with a maximum Mercalli intensity of X (Extreme), killing 2,483–4,900, and injuring 7,700–8,934.
December 11 » The Comprehensive Environmental Response, Compensation, and Liability Act (Superfund) is enacted by the U.S. Congress.
When copying data from this family tree, please include a reference to the origin: Hendrik Dreyer, "Dreyer Tree", database, Genealogy Online (https://www.genealogieonline.nl/dreyer-tree/I18762.php : accessed January 24, 2026), "Roelof Jacobus Coertze (1897-1980)".
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