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.
August 10 » German chemist Felix Hoffmann discovers an improved way of synthesizing acetylsalicylic acid (aspirin).
August 21 » Oldsmobile, an American automobile manufacturer and marque, is founded.
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 6 » London becomes the world's first city to host licensed taxicabs.
December 30 » The British Colony of Natal annexes Zululand.
Day of death February 13, 1939
The temperature on February 13, 1939 was between 2.2 °C and 6.6 °C and averaged 4.6 °C. There was 0.5 mm of rain during 0.6 hours. There was -0.1 hours of sunshine (0%). The average windspeed was 4 Bft (moderate breeze) and was prevailing from the west-northwest. Source: KNMI
In The Netherlands , there was from June 24, 1937 to July 25, 1939 the cabinet Colijn IV, with Dr. H. Colijn (ARP) as prime minister.
In The Netherlands , there was from July 25, 1939 to August 10, 1939 the cabinet Colijn V, with Dr. H. Colijn (ARP) as prime minister.
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.
April 30 » NBC inaugurates its regularly scheduled television service in New York City, broadcasting President Franklin D. Roosevelt's N.Y. World's Fair opening day ceremonial address.
May 17 » The Columbia Lions and the Princeton Tigers play in the United States' first televised sporting event, a collegiate baseball game in New York City.
August 2 » Albert Einstein and Leo Szilard write a letter to Franklin D. Roosevelt, urging him to begin the Manhattan Project to develop a nuclear weapon.
September 17 » World War II: The Soviet invasion of Poland begins.
November 4 » World War II: U.S. President Franklin D. Roosevelt orders the United States Customs Service to implement the Neutrality Act of 1939, allowing cash-and-carry purchases of weapons by belligerents.
December 17 » World War II: Battle of the River Plate: The Admiral Graf Spee is scuttled by Captain Hans Langsdorff outside Montevideo.
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/I102597.php : accessed October 16, 2026), "Sybren Adema (1897-1939)".
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