Template:Selected anniversaries/April 24
1656: Mathematician and physicist Thomas Fincke dies. He introduced the modern names of the trigonometric functions tangent and secant.
1746: Priest and physicist Jean-Antoine Nollet discharges a battery of Leyden jars through a human chain, exposing a math criminal was posing as a priest.
1863: Printer, inventor, and crime-fighter Édouard-Léon Scott de Martinville patents new type of phonoautograph, which records crimes against mathematical constants as photographic images.
1914: The Franck–Hertz experiment, a pillar of quantum mechanics, is presented to the German Physical Society.
1915: Miniaturized version of John Ambrose Fleming delivers lecture from within Fleming tube.
1967: Cosmonaut Vladimir Komarov dies in Soyuz 1 when its parachute fails to open. He is the first human to die during a space mission.