April 18 » The Greco-Turkish War is declared between Greece and the Ottoman Empire.
April 30 » J. J. Thomson of the Cavendish Laboratory announces his discovery of the electron as a subatomic particle, over 1,800 times smaller than a proton (in the atomic nucleus), at a lecture at the Royal Institution in London.
July 2 » British-Italian engineer Guglielmo Marconi obtains a patent for radio in London.
August 10 » German chemist Felix Hoffmann discovers an improved way of synthesizing acetylsalicylic acid (aspirin).
August 31 » Thomas Edison patents the Kinetoscope, the first movie projector.
September 11 » After months of pursuit, generals of Menelik II of Ethiopia capture Gaki Sherocho, the last king of Kaffa, bringing an end to that ancient kingdom.
Day of marriage September 16, 1916
The temperature on September 16, 1916 was between 9.0 °C and 15.9 °C and averaged 11.9 °C. There was 2.0 mm of rain. There was 3.6 hours of sunshine (28%). The average windspeed was 3 Bft (moderate breeze) and was prevailing from the west-northwest. 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 24 » In Brushaber v. Union Pacific Railroad Co., the Supreme Court of the United States declares the federal income tax constitutional.
March 16 » The 7th and 10th US cavalry regiments under John J. Pershing cross the US–Mexico border to join the hunt for Pancho Villa.
May 6 » Vietnamese Emperor Duy Tân is captured while calling upon the people to rise up against the French, and is later deposed and exiled to Réunion island.
May 31 » World War I: Battle of Jutland: The British Grand Fleet engages the High Seas Fleet in the largest naval battle of the war, which proves indecisive.
August 2 » World War I: Austrian sabotage causes the sinking of the Italian battleship Leonardo da Vinci in Taranto.
August 28 » World War I: Italy declares war on Germany.
Day of death August 13, 1975
The temperature on August 13, 1975 was between 15.8 °C and 29.3 °C and averaged 22.8 °C. There was -0.1 mm of rain. There was 8.6 hours of sunshine (58%). The partly clouded was. The average windspeed was 2 Bft (weak wind) and was prevailing from the north-northeast. Source: KNMI
In The Netherlands , there was from Friday, May 11, 1973 to Monday, December 19, 1977 the cabinet Den Uyl, with Drs. J.M. den Uyl (PvdA) as prime minister.
March 6 » Algiers Accord: Iran and Iraq announce a settlement of their border dispute.
April 29 » Vietnam War: Operation Frequent Wind: The U.S. begins to evacuate U.S. citizens from Saigon before an expected North Vietnamese takeover. U.S. involvement in the war comes to an end.
May 10 » Sony introduces the Betamax videocassette recorder.
May 27 » Dibbles Bridge coach crash near Grassington, in North Yorkshire, England, kills 33 – the highest ever death toll in a road accident in the United Kingdom.
July 5 » Cape Verde gains its independence from Portugal.
October 16 » Three-year-old Rahima Banu, from Bangladesh, is the last known case of naturally occurring smallpox.
When copying data from this family tree, please include a reference to the origin: J. Ham, "Family tree Ham", database, Genealogy Online (https://www.genealogieonline.nl/stamboom-ham/I69425.php : accessed March 13, 2026), "Catharina Arendina Hendrika Witkop (1897-1975)".
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