Inventions of the Early to Mid-20th Century

1920: First American radio broadcast station opened by Westinghouse, in Pittsburgh
1920: Autogyro invented by de la Cierva (Spain)
1921: Nitrocellulose lacquer invented by Flaherty (USA)
1921: Oil-filled power cable invented by Emanueli (Italy)
1921: First radio broadcast of a baseball game, from Polo Grounds, New York
1922: Gasoline (Lead Ethyl) invented by Midgley (USA)
1922: Insulin discovered by Banting, Best & Macleod (Scotland)
1922: Vitamin D discovered by McCollum (USA)
1922: Gas discharge tube invented by Hull (USA)
1922: Self-winding wristwatch invented by John Harwood (patented 1924)
1923: Electric razor patented by Colonel Jacb Schick (USA)
1923: Television mechanical scanner invented by John Logie Baird (Scotland)
1923: Television Iconoscope invented by Zworykin (USA)
1923: First birth control clinic opens in New York
1924: Mah-Jong craze spreads worldwide
1924: Frozen food invented by Birdseye (USA)
1924: Frosted incandescent lightbulb invented by Pipkin (USA)
1924: Dynamic loudspeaker invented by Rice & Kellog (USA)
1924: Atomic hydrogen welding invented by Langmuir & Palmer (USA)
1924: Bromine from seawater discovered by Edgar Kramer (USA)
1925: John Logie Baird transmits recognizable human faces by television
1925: The Charleston dance leaps to popularity
1925: Circuit breaker invented by Hilliard (USA)
1925: Phototelegraphy invented at Bell Labs (USA)
1925: Carbon oxides discovered by Fischer (Germany)
1925: Fischer-Tropsch synthesis, leads to synthetic oil
1926: First liquid-fueled rocket fired, by inventor Robert Goddard (USA)
1926: Cushioned cork-center baseball enters professional use
1926: Aerosol spray invented by Rotheim (Norway)
1926: Book-of-the-Month Club founded (USA)
1926: First 16-mm movie film (Kodak)
1927: Charles A. Lindbergh flies airplane nonstop New York to Paris
1927: Airplanes first "dust" crops with insecticide (Canadian forest trees)
1927: Talking movie, invented at Warner Bros (USA)
1927: Electronic television invented by Philo Farnsworth (USA)
1927: ACTH discovered by Evans & Long (USA)
1927: Slow fox trot the popular dance
1928: Penicillin discovered by Alexander Fleming
1928: Color Television demonstrated by John Logie Baird (Scotland)
1928: First scheduled television broadcasts, WGY, Schenectady, New York
1928: Iron lung invented by P. Drinker & L. A. Shaw (USA)
1928: Radio beacon invented by Donovan (USA)
1928: Hardwater soap invented by Bertsch (Germany)
1928: Teletype invented by Morkrum & Kleinschmidt (Germany)
1928: Vitamin C discovered by Szent-Gyorgyi & King (USA)
1929: Coaxial cable system invented by Affel & Espensched (USA)
1929: Electroencephalograph invented by Berger (Germany)
1929: Practical use of Penicillin perfected by Florey & Chain (England)
1930: Planet discovered: Pluto, by Clyde W. Tombaugh at Lowell Observatory
1930: Photoflash bulb
1930: Freon invented by Midgley et al.
1930: Artificial fabric polymerized from acetylene (J. Walter Reppe, Germany)
1930: High-octane gasoline invented by Ipatief (Russia)