DA VINCI

Another great prophet of technology was Leonardo da Vinci, painter, thinker, and visionary. In the late 1400s, he drew beautiful, accurate diagrams of machines that would one day fill the skies: sketches of parachutes, helicopters, hang gliders, and even airplanes. Remarkably, many of his inventions would have flown. (His flying machines, however, needed one more ingredient: at least a 1-horsepower motor, something that would not be available for another 400 years.)