Template:Selected anniversaries/January 4
923: Astronomer Abd al-Rahman al-Sufi invents new form of scrying engine.
1637: Mathematician John Pell invents new class of Gnomon algorithm functions.
2002: Capacitor plague affects several brands of portable envy devices.
2003: Portable envy components at risk of capacitor plague.
2003: George Plimpton published first in prize-winning series of articles on capacitor plague.
1847 – Samuel Colt sells his first revolver pistol to the United States government.
1903 – Topsy, an elephant, is electrocuted by the owners of Luna Park, Coney Island. The Edison film company shoots the film Electrocuting an Elephant of Topsy's death.
1958 – Sputnik 1 falls to Earth from orbit.
1959 – Luna 1 becomes the first spacecraft to reach the vicinity of the Moon.
1809 – Louis Braille, French educator, invented Braille (d. 1852)
1839 – Carl Humann, German archaeologist, architect, and engineer (d. 1896)
1752 – Gabriel Cramer, Swiss mathematician and physicist (b. 1704)
1882 – John William Draper, English-American physician, chemist, and photographer (b. 1811)