Sep 20, 1819: The first patent leather manufactured in the U.S. was produced in Newark, N.J., by Seth Boyden. Boyden also invented a variety of other things including malleable cast iron, a nail-making machine, a cut-off switch for steam engines, a method for refining zinc from its ore and he developed a hybrid strawberry.

Sep 20, 1842: Scottish chemist and physicist, Sir James Dewar, who blurred the line between physics and chemistry was born. He gave dazzling lectures and his study of low-temperature phenomena led him to invent the Dewar flask, an insulating double-walled flask that uses a vacuum between two silvered layers of steel or glass. These are sometimes called vacuum flasks, but usually just “Dewars”. A domestic “Thermos” bottle is a Dewar flask. In June of 1897, it was reported that Dewar had succeeded in liquefying fluorine gas at a temperature of -185 degrees Celsius or 88 degrees Kelvin. He obtained liquid hydrogen in 1898, which requires a temperature below 33 Kelvin. Dewar also invented cordite, the first smokeless powder.

Sep 20, 1848: The first meeting of the American Association for the Advancement of Science (AAAS) was held at noon, in the library of the Academy of Natural Science, Philadelphia, Pennsylvania. The goal of the organization recorded in its original Rules and Objects included “to give a stronger and more general impulse, and a more systematic direction to scientific research in our country; and to procure for the labours of scientific men, increased facilities and a wider usefulness.”

Sep 20, 1853: Elisha Graves Otis sold his first safety elevator equipment. His customer was Benjamin Newhouse in New York City who used it for moving freight. In May 1854, at the Crystal Palace in New York City, Otis created public interest with a daring demonstration. He was hoisted high in the air on a platform fitted with his safety feature. When the rope was cut, the safety device stopped his fall. By 1857, he had installed the first department store passenger elevator. In 1889 he introduced the electric motor to power elevators.

Sep 20, 1859: A patent for the electric range was granted to George B. Simpson of Washington, D.C.. Simpson called his invention, an “electroheater.” Heat was generated by passing electricity through wire coils.

Sep 20, 1862: A patent for a revolving turret for battleships was granted to Theodore Ruggles Timby. The patent described “a revolving tower for defensive and offensive warfare, whether placed on land or water.” John Ericsson incorporated this design when building the ironclad ship, Monitor, the world’s first turret battleship. Timby was paid a royalty for the use of his patent.

Sep 20, 1888: American pathologist, David Marine, was born. His research on the treatment of goiter with iodine led to the iodizing of table salt. Goiter is a disease that causes major swelling of the thyroid gland in the neck. During 1917-22 he ran a trial on a large group of schoolgirls to show that an iodine supplement dramatically reduced the incidence of goiter. The results clearly showed the importance of iodine in the diet. Iodized table salt was first sold on May 1, 1924. Marine then worked with the World Health Organization to spread this knowledge around the world.

It’s interesting to note that French chemist Jean-Baptiste Boussingault observed that iodine-rich salt could treat goiter, but nothing was done with this information.

Sep 20, 1892: Wired glass or wire glass was patented by Frank Schulman. Wire glass, is plate glass with a wire mesh inside, which is useful for fire safety and security.

Sep 20, 1904: The first circular flight in an airplane happened on this day. On Sep 15, 1904, Wilbur was able to fly a half-circle. As the brothers improved the control of their airplane’s flight, a few days later, a complete circuit was accomplished. The flight was made by Orville Wright at Huffman Prairie, near Dayton, Ohio. The flight covered about 4,080 feet in 1-1/2 minutes. The flight was made in the Flyer II, an improved aircraft built after the first Flyer was overturned and damaged by wind in North Carolina.

Sep 20, 1952: Alfred Hershey and Martha Chase published a report confirming that DNA holds hereditary data.

Sep 20, 1954: On this day, the first successful compilation and execution of a computer program using what became FORTRAN was run by Harlan Herrick at IBM. It took until 1957 to develop an operational commercial product. FORTRAN (FORmula TRANslator) was designed as a high-level language aimed at technical and scientific applications that performed calculations, rather than primarily working with characters.

John Backus at IBM supervised the development of FORTRAN, which allowed users to express problems as commonly understood equations. By 1958, the language had grown to become Fortran II, which included subroutines, functions, and common blocks. Fortran IV was introduced by IBM in 1962.

Sep 20, 2013: The Deep Impact spacecraft was declared dead by NASA after nine productive years making fly-bys of comets. Radio contact was lost on Aug 8, 2013, possibly caused by solar panel failure. Without power, the craft likely froze up. Deep Impact released an impactor craft to crash into the comet Tempel 1 on July 3, 2005. On July 4, 2005, the plume of debris created by the impactor was studied to reveal its composition. Deep Impact performed fly-bys of several other comets.