Template:Selected anniversaries/January 9: Difference between revisions
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||1868 – S. P. L. Sørensen, Danish chemist and academic (d. 1939) | ||1868 – S. P. L. Sørensen, Danish chemist and academic (d. 1939) | ||
||Richard Wilhelm Heinrich Abegg (b. January 9, 1869) was a German chemist and pioneer of valence theory. He proposed that the difference of the maximum positive and negative valence of an element tends to be eight. This has come to be known as Abegg's rule. Pic. | |||
||1870 – Joseph Strauss, American engineer, co-designed the Golden Gate Bridge (d. 1938) | ||1870 – Joseph Strauss, American engineer, co-designed the Golden Gate Bridge (d. 1938) | ||
Revision as of 19:03, 26 January 2018
1799: Mathematician, philosopher, theologian, and humanitarian Maria Gaetana Agnesi dies. She is credited with writing the first book discussing both differential and integral calculus.
1800: Poet-Wizard Jan Kochanowski adapts Nebra sky disk for use as scrying engine.
1848: Astronomer Caroline Herschel dies. She discovered several comets, including the periodic comet 35P/Herschel-Rigollet, which bears her name.
1894: New England Telephone and Telegraph installs the first battery-operated telephone switchboard in Lexington, Massachusetts. (Shown here: another telephone exchange circa 1900.)
1917: Mathematician and philosopher Georg Cantor publishes new theory of sets derived from Gnomon algorithm functions. Colleagues hail it as "a magisterial contribution to science and art of detecting and preventing crimes against mathematical constants."
1989: Mathematician Marshall Harvey Stone dies. He contributed to real analysis, functional analysis, topology, and the study of Boolean algebra structures.