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1920 |
- Autogyro invented by de la Cierva
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1921 |
- Lacquer, Nitrocellulose invented by Flaherty
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1922 |
- Elevator push button invented by Larson
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1923 |
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1924 |
- Eliason develops first snowmobile
- Frozen food invented by Birdseye
- Dynamic Loudspeaker invented by Rice & Kellog
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1925 |
- Circuit Breaker invented by Hillard
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1926 |
- Aerolsole spray invented by Rotheim
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1927 |
- Eliason Patents snwomobile
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1928 |
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1929 |
- Electrostatic generator invented by Van De Graaff
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1930 |
- Freon invented by Midgley
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1931 |
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1932 |
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1933 |
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1934 |
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1935 |
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1936 |
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1937 |
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1938 |
- Fiberglass invented by Owens-Corning
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1939 |
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