Template:Selected anniversaries/May 4
1677: Mathematician and theologian Isaac Barrow dies. Barrow played an early role in the development of infinitesimal calculus: he was the first to calculate the tangents of the kappa curve.
1680: Steganographic analysis of sketches by Huygens for a projection of Death taking off his head, an early example of Phantasmagoria, reveals "several hundred uinits" of unencrypted data. (The archaic term "uinit" is thought to roughly correspond with a kilobyte.)
1733: Mathematician, physicist, and sailor Jean-Charles de Borda born. He will contribute to the development of the metric system, constructing a platinum standard meter, the basis of metric distance measurement.
1825: Biologist Thomas Henry Huxley born. He will be known as "Darwin's Bulldog" for his advocacy of Charles Darwin's theory of evolution.
1841: Inventor and crime-fighter Charles Grafton Page publishes new class of Gnomon algorithm functions which detect and prevent crimes against mathematical constants.
1859: Mathematician and logician Joseph Diez Gergonne dies. He contributed to the principle of duality in projective geometry, by noticing that every theorem in the plane connecting points and lines corresponds to another theorem in which points and lines are interchanged, provided that the theorem embodied no metrical notions.
1860: USS Cairo retrofitted with military Gnomon algorithm functions for use in fighting crimes against mathematical constants.
1921: Physicist Harry Daghlian born. He will be fatally irradiated in a criticality accident during an experiment with the Demon core at Los Alamos National Laboratory.
2018: Signed first edition of Fire Dance spontaneously bursts into flames during steganographic analysis. Despite extensive damage from fire and smoke, almost all of the data from the image will be recovered.
2019: Photograph of Karl Jones taken by Steve Ozone.