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 21 » Oldsmobile, an American automobile manufacturer and marque, is founded.
August 31 » Thomas Edison patents the Kinetoscope, the first movie projector.
December 30 » The British Colony of Natal annexes Zululand.
Day of marriage April 17, 1919
The temperature on April 17, 1919 was between 3.8 °C and 10.8 °C and averaged 7.2 °C. There was 0.7 mm of rain. There was 2.5 hours of sunshine (18%). The average windspeed was 4 Bft (moderate breeze) and was prevailing from the northwest. 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 1 » March 1st Movement begins in Korea under Japanese rule.
April 13 » Jallianwala Bagh massacre: British Indian Army troops lead by Brigadier-General Reginald Dyer killed approx 379-1000 unarmed demonstrators including men and women in Amritsar, India; and approximately 1,500 injured.
July 6 » The British dirigible R34 lands in New York, completing the first crossing of the Atlantic Ocean by an airship.
August 8 » The Anglo-Afghan Treaty of 1919 is signed. It establishes peaceful relations between Afghanistan and the UK, and confirms the Durand line as the mutual border. In return, the UK is no longer obligated to subsidize the Afghan government.
September 18 » The Netherlands gives women the right to vote.
December 17 » Uruguay becomes a signatory to the Buenos Aires copyright treaty.
When copying data from this family tree, please include a reference to the origin: Wim Ackermans, "Family tree Ackermans", database, Genealogy Online (https://www.genealogieonline.nl/stamboom-ackermans/I792.php : accessed March 10, 2026), "Jannetje Grootveld (1897-????)".
Copy warning
Genealogical publications are copyright protected. Although data is often retrieved from public archives, the searching, interpreting, collecting, selecting and sorting of the data results in a unique product. Copyright protected work may not simply be copied or republished.
Please stick to the following rules
Request permission to copy data or at least inform the author, chances are that the author gives permission, often the contact also leads to more exchange of data.
Do not use this data until you have checked it, preferably at the source (the archives).
State from whom you have copied the data and ideally also his/her original source.