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Births on July 5

A. E. Douglass
1867Jul, 5

A. E. Douglass

A. E. Douglass, American astronomer (d. 1962)
A. E. (Andrew Ellicott) Douglass (July 5, 1867 in Windsor, Vermont – March 20, 1962 in Tucson, Arizona) was an American astronomer. He discovered a correlation between tree rings and the sunspot cycle, and founded the discipline of dendrochronology, which is a method of dating wood by analyzing the growth ring pattern. He started his discoveries in this field in 1894 when he was working at the Lowell Observatory. During this time he was an assistant to Percival Lowell, but fell out with him when his experiments made him doubt the existence of artificial "canals" on Mars and visible cusps on Venus.

Craters on the Moon and Mars are named in his honor.

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Events on 1867

  • 29Mar

    British North America Act

    Queen Victoria gives Royal Assent to the British North America Act which establishes the Dominion of Canada on July 1.
  • 1Apr

    Crown colony

    Singapore becomes a British crown colony.
  • 15May

    Imperial Bank of Canada

    Canadian Bank of Commerce opens for business in Toronto. The bank would later merge with Imperial Bank of Canada to become what is CIBC in 1961.
  • 3Nov

    Battle of Mentana

    Giuseppe Garibaldi and his followers are defeated in the Battle of Mentana and fail to end the Pope's Temporal power in Rome (it would be achieved three years later).
  • 9Nov

    Meiji Restoration

    Tokugawa shogunate hands power back to the Emperor of Japan, starting the Meiji Restoration.