Sep 17, 1683: Dutch scientist Antonie van Leeuwenhoek wrote to the Royal Society reporting his discovery of microscopic living animalcules (live bacteria). He had made observations on the plaque between his own teeth.

Sep 17, 1822: Jean-François Champollion, at the French Academie Royale des Inscriptions, read a paper on his solution to the mystery of the triple inscriptions on the Rosetta Stone. He had worked on deciphering the hieroglyphics for 14 years.

Sep 17, 1844:  Thomas F. Adams of Philadelphia, PA is issued the first U.S. patent (3,744) for a printing press that applied different colors of ink in one impression. The inventor called it polychrome printing.

Sep 17, 1871: The world’s first major mountain tunnel, the Mont Cenis Tunnel is opened. It burrows eight miles through granite under the Alps, linking Switzerland and Northern Italy. The tunnel is wide enough to accommodate two railroad tracks. Started in 1857, for the first three years, progress was only 8 inches a day. Then, Germain Sommeiller introduced the first high-powered pneumatic tools to tunneling, greatly speeding up the work.

Sep 17, 1872: Phillip W. Pratt is issued the first U.S. patent (131,370) for an automatic fire sprinkler system. This first system used valves held closed by springs and cords. The cords were equipped with fuses. Fire would ignite the fuses, burning the cords and releasing the valves.

Sep 17, 1901: Peter Cooper Hewitt is issued the first U.S. patents (682,692-682,699) for a mercury vapor light. The design consisted of a long glass tube with a mercury electrode at one end and an iron one at the other. Electric current through the tube produced a stark blue-green light with no red. Lamps of this type were common for street lighting in the middle of the 20th Century. They were ugly but much more efficient than incandescent lights, and were manufactured by the Cooper Hewitt Electric Company of New York. Hewitt’s invention was a forerunner of modern fluorescent lamps.

Sep 17, 1906: Three men from Shackleton’s Nimrod Expedition, Douglas Mawson, Edgeworth David and Alistair Mackay, walk over 1,200 miles across perilous Antarctica and claim to have located the Magnetic South Pole, which they claimed for the British Empire.

Sep 17, 1908: Thomas Etholen Selfridge becomes the first airplane fatality in the U.S. at Arlington Heights, Virginia. He was a passenger with Orville Wright, demonstrating the Wright Flier airplane to the Army. Wright had installed new, longer propellers the day before but had not flight tested them. One of the propellers struck one of the wings’ guy wires and disintegrated. The aircraft fell 75 feet and crashed. Selfridge was 26 and an officer with the Balloon Corps. He died of a fractured skull. Wright suffered a fractured thigh and several fractured ribs.

Sep 17, 1911: “Cal” (Calbraith Perry) Rogers began the first transcontinental flight across the U.S. in a 35 horsepower Wright biplane. Forty-nine days, 30 stops, 82 flying hours, and 19 crashes later, he completed the flight in Pasadena, California. By the time he arrived he had completely rebuilt the aircraft at least once. He was sponsored by a soft drink maker, Vin Fiz. William Randolph Hearst was offering a $50,000 prize to the first person to complete such a flight in 30 days or less. Rogers was 19 days too slow to win the prize.

Sep 17, 1931: Early 33 RPM long-playing (LP) records were first demonstrated at the Savoy Plaza Hotel in New York by RCA (Radio Corporation of America). The equipment was too expensive to become a practical product. The first vinyl LP records and more practical equipment came out in 1948, produced by RCA’s competitor, Columbia.

Sep 17, 1953: The first successful surgical separation of siamese twins took place at the Ochsner Foundation Hospital in New Orleans, Louisiana. Carolyn Anne and Catherine Anne Mouton were connected at the waist and were born in July of 1953.

Sep 17, 1991: Birth of the Linux operating system. The first Linux kernel was released by Linus Torvalds.