1809 in science
The year 1809 in science and technology involved some significant events, listed below.
Astronomy
- Carl Friedrich Gauss publishes Theoria motus corporum coelestium in sectionibus conicis solem ambientum in Hamburg, introducing the Gaussian gravitational constant and containing an influential treatment of the least squares method.
- S. D. Poisson publishes Sur les inégalités séculaires des moyens mouvements des planètes and Sur la variation des constantes arbitraires dans les questions de mécanique in the Journal of the École Polytechnique, extending Lagrange's theory of planetary orbits.
Biology
- Jean-Baptiste Lamarck publishes Philosophie Zoologique, outlining his theory of evolution.
- Johann [Heinrich Friedrich Link] first describes Penicillium.
Geology
- William Maclure publishes the first geological map of the United States with accompanying memoir.
Mathematics
- Louis Poinsot describes the two remaining Kepler-Poinsot polyhedra.
Medicine
- December 25 – American physician Ephraim McDowell performs the world's first ovariotomy, the removal of an ovarian tumor.
- Philippe Pinel publishes accounts of what would later be regarded as schizophrenia.
Technology
- February 11 – Robert Fulton patents the steamboat in the United States.
- May 5 – Mary Kies becomes one of the first women granted a U.S. patent, for a technique of weaving straw hats with silk and thread.
- Samuel Thomas von Sömmerring invents a water voltameter electrical telegraph.
- William Hyde Wollaston invents the reflecting goniometer.
Awards
Births
- January 4 – Louis Braille, French inventor.
- January 6 – Marie Durocher, Brazilian physician.
- February 12 – Charles Darwin, English naturalist.
- February 15 – Cyrus McCormick, American inventor.
- February 21 – Carl Ernst Bock, German physician and anatomist.
- April 7 – James Glaisher, English meteorologist and balloonist.
- April 15 – Hermann Grassmann, German mathematician.
- April 20 – James David Forbes, Scottish physicist, glaciologist and seismologist.
- August 29 – Oliver Wendell Holmes Sr., American physician and writer.
- November 22 – Bénédict Morel, French psychiatrist.
- Date unknown – William Lobb, English plant collector.
Deaths
- May 17 – Leopold Auenbrugger, Austrian physician.
- August 18 – Matthew Boulton, English mechanical engineer.
- October 11 – Meriwether Lewis, American explorer.
- December 16 – Antoine François, comte de Fourcroy, French chemist.
- December 29 – Thomas Barker, English meteorologist.