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.
February 19 » More than sixty tornadoes strike the Southern United States, one of the largest tornado outbreaks in U.S. history.
May 1 » The Federation of Organized Trades and Labor Unions demands the eight-hour work day in the United States.
July 3 » Dow Jones & Company publishes its first stock average.
July 5 » Germany takes possession of Cameroon.
October 6 » The Naval War College of the United States is founded in Rhode Island.
October 22 » The International Meridian Conference designates the Royal Observatory, Greenwich as the world's prime meridian.
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.
February 18 » The first official flight with airmail takes place from Allahabad, United Provinces, British India (now India), when Henri Pequet, a 23-year-old pilot, delivers 6,500 letters to Naini, about 10 kilometres (6.2mi) away.
June 28 » The Nakhla meteorite, the first one to suggest signs of aqueous processes on Mars, falls to Earth, landing in Egypt.
July 4 » A massive heat wave strikes the northeastern United States, killing 380 people in eleven days and breaking temperature records in several cities.
July 7 » The United States, UK, Japan, and Russia sign the North Pacific Fur Seal Convention of 1911 banning open-water seal hunting, the first international treaty to address wildlife preservation issues.
September 1 » The armored cruiser Georgios Averof is commissioned into the Greek Navy. It now serves as a museum ship.
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.
March 14 » Alam Ara, India's first talking film, is released.
March 23 » Bhagat Singh, Shivaram Rajguru and Sukhdev Thapar are hanged for the killing of a deputy superintendent of police during the Indian independence movement.
March 31 » A Transcontinental & Western Air airliner crashes near Bazaar, Kansas, killing eight, including University of Notre Dame head football coach Knute Rockne.
September 30 » Start of "Die Voortrekkers" youth movement for Afrikaners in Bloemfontein, South Africa.
October 1 » The George Washington Bridge in the United States, linking New Jersey and New York, is opened.
November 7 » The Chinese Soviet Republic is proclaimed on the anniversary of the October Revolution.
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 3, 2026), "Roelf Potze (1884-1931)".
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