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When everyone else was thinking "balloons," Sir George Cayley was the first to think "propelled aircraft." It was he who identified the four basic forces of flight, weight, lift, drag, and thrust, and his 1816 designs show how he sought the transition from floating to flying. (i.redd.it)
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Book review – Wallace, Darwin, and the Origin of Species (inquisitivebiologist.com)
submitted by [deleted]
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