The temperature on June 9, 1884 was about 14.5 °C. There was 0.9 mm of rain. The air pressure was 1 kgf/m2 and came mainly from the west-southwest. The airpressure was 76 cm mercury. The atmospheric humidity was 78%. Source: KNMI
In The Netherlands , there was from April 23, 1884 to April 21, 1888 the cabinet Heemskerk, with Mr. J. Heemskerk Azn. (conservatief) as prime minister.
March 13 » The Siege of Khartoum begins. It lasts until January 26, 1885.
March 27 » A mob in Cincinnati, Ohio, attacks members of a jury which had returned a verdict of manslaughter in what was seen as a clear case of murder; over the next few days the mob would riot and eventually destroy the courthouse.
June 16 » The first purpose-built roller coaster, LaMarcus Adna Thompson's "Switchback Railway", opens in New York's Coney Island amusement park.
July 5 » Germany takes possession of Cameroon.
October 6 » The Naval War College of the United States is founded in Rhode Island.
December 6 » The Washington Monument in Washington, D.C., is completed.
Day of marriage May 6, 1911
The temperature on May 6, 1911 was between 2.7 °C and 13.9 °C and averaged 8.6 °C. There was 12.1 hours of sunshine (80%). The average windspeed was 3 Bft (moderate breeze) and was prevailing from the north. Source: KNMI
January 12 » The University of the Philippines College of Law is formally established; three future Philippine presidents are among the first enrollees.
January 18 » Eugene B. Ely lands on the deck of the USSPennsylvania anchored in San Francisco Bay, the first time an aircraft landed on a ship.
April 27 » Following the resignation and death of William P. Frye, a compromise is reached to rotate the office of President pro tempore of the United States Senate.
August 1 » Harriet Quimby takes her pilot's test and becomes the first U.S. woman to earn an Aero Club of America aviator's certificate.
August 21 » The Mona Lisa is stolen by Vincenzo Peruggia, a Louvre employee.
November 5 » After declaring war on the Ottoman Empire on September 29, 1911, Italy annexes Tripoli and Cyrenaica.
Day of death December 21, 1931
The temperature on December 21, 1931 was between -1.2 °C and 2.0 °C and averaged 0.4 °C. The average windspeed was 3 Bft (moderate breeze) and was prevailing from the east-northeast. Source: KNMI
In The Netherlands , there was from August 10, 1929 to May 26, 1933 the cabinet Ruys de Beerenbrouck III, with Jonkheer mr. Ch.J.M. Ruys de Beerenbrouck (RKSP) as prime minister.
January 21 » Sir Isaac Isaacs is sworn in as the first Australian-born Governor-General of Australia.
March 14 » Alam Ara, India's first talking film, is released.
March 31 » A Transcontinental & Western Air airliner crashes near Bazaar, Kansas, killing eight, including University of Notre Dame head football coach Knute Rockne.
May 1 » The Empire State Building is dedicated in New York City.
May 14 » Five unarmed civilians are killed in the Ådalen shootings, as the Swedish military is called in to deal with protesting workers.
December 11 » Statute of Westminster 1931: The British Parliament establishes legislative equality between the UK and the Dominions of the Commonwealth—Australia, Canada, Newfoundland, New Zealand, South Africa, and Ireland.
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/I1500.php : accessed February 1, 2026), "Roelf Potze (1884-1931)".
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