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.
June 16 » A treaty annexing the Republic of Hawaii to the United States is signed; the Republic would not be dissolved until a year later.
June 22 » British colonial officers Charles Walter Rand and Lt. Charles Egerton Ayerst are assassinated in Pune, Maharashtra, India by the Chapekar brothers and Mahadeo Vinayak Ranade, who are later caught and hanged.
July 11 » Salomon August Andrée leaves Spitsbergen to attempt to reach the North Pole by balloon. He later crashes and dies.
December 30 » The British Colony of Natal annexes Zululand.
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The Family tree Van Willigen publication was prepared by Rob van Willigen (contact is not possible).
When copying data from this family tree, please include a reference to the origin: Rob van Willigen, "Family tree Van Willigen", database, Genealogy Online (https://www.genealogieonline.nl/stamboom-van-willigen/I4422.php : accessed January 19, 2026), "Gerrit Dijkman de Groot (1875-????)".
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