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.
April 20 » Pope Leo XIII publishes the encyclical Humanum genus.
May 1 » Moses Fleetwood Walker becomes the first black person to play in a professional baseball game in the United States.
May 31 » The arrival at Plymouth of Tāwhiao, King of Maoris, to claim the protection of Queen Victoria.
July 5 » Germany takes possession of Cameroon.
October 22 » The International Meridian Conference designates the Royal Observatory, Greenwich as the world's prime meridian.
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 3 » A gun battle in the East End of London left two dead and sparked a political row over the involvement of then-Home Secretary Winston Churchill.
January 3 » A magnitude 7.7 earthquake destroys the city of Almaty in Russian Turkestan.
May 15 » In Standard Oil Co. of New Jersey v. United States, the United States Supreme Court declares Standard Oil to be an "unreasonable" monopoly under the Sherman Antitrust Act and orders the company to be broken up.
May 31 » The RMS Titanic is launched in Belfast, Northern Ireland.
September 29 » Italy declares war on the Ottoman Empire.
October 24 » Orville Wright remains in the air nine minutes and 45 seconds in a glider at Kill Devil Hills, North Carolina.
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.
February 13 » The British Raj completes its transfer from Calcutta to New Delhi.
February 20 » The U.S. Congress approves the construction of the San Francisco–Oakland Bay Bridge by the state of California.
March 31 » A Transcontinental & Western Air airliner crashes near Bazaar, Kansas, killing eight, including University of Notre Dame head football coach Knute Rockne.
October 1 » Clara Campoamor persuades the Constituent Cortes to enfranchise women in Spain's new constitution.
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 2, 2026), "Roelf Potze (1884-1931)".
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