Portal:History of science/Selected anniversaries/January 19
- 1833 - Birth of Alfred Clebsch, German mathematician (d. 1872)
- 1851 - Birth of Jacobus Kapteyn, Dutch astronomer (d. 1922)
- 1869 - Death of Carl Reichenbach, German chemist and philosopher (b. 1788)
- 1878 - Death of Henri Victor Regnault French physicist and chemist (b. 1810)
- 1883 - The first electric lighting system employing overhead wires, built by Thomas Edison, begins service at Roselle, New Jersey
- 1908 - Birth of Aleksandr Gennadievich Kurosh, Russian mathematician (d. 1971)
- 1915 - Georges Claude patents the neon discharge tube for use in advertising
- 1954 - Death of Theodor Kaluza, German scientist (b. 1885)