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.
May 26 » Dracula, a Gothic horror novel by Irish author Bram Stoker, is published.
August 31 » Thomas Edison patents the Kinetoscope, the first movie projector.
November 1 » The first Library of Congress building opens its doors to the public; the library had previously been housed in the Congressional Reading Room in the U.S. Capitol.
December 9 » Activist Marguerite Durand founds the feminist daily newspaper La Fronde in Paris.
December 30 » The British Colony of Natal annexes Zululand.
Day of death July 30, 1973
The temperature on July 30, 1973 was between 13.7 °C and 18.0 °C and averaged 15.7 °C. There was 0.9 mm of rain during 1.0 hours. There was 0.3 hours of sunshine (2%). The heavily 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 Thursday, July 20, 1972 to Friday, May 11, 1973 the cabinet Biesheuvel II, with Mr. B.W. Biesheuvel (ARP) as prime minister.
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 29 » Vietnam War: The last United States combat soldiers leave South Vietnam.
May 29 » Tom Bradley is elected the first black mayor of Los Angeles, California.
July 11 » Varig Flight 820 crashes near Paris, France on approach to Orly Airport, killing 123 of the 134 on board. In response, the FAA bans smoking in airplane lavatories.
July 25 » Soviet Mars 5 space probe is launched.
November 1 » The Indian state of Mysore is renamed as Karnataka to represent all the regions within Karunadu.
November 27 » Twenty-fifth Amendment: The United States Senate votes 92–3 to confirm Gerald Ford as Vice President of the United States. (On December 6, the House will confirm him 387–35).
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/I201937.php : accessed October 13, 2026), "Pieter Olthof (1897-1973)".
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