> So why did it then take almost another half a century, even with the increasingly widespread understanding of atmospheric pressure and vacuums, for a widely-a

> So why did it then take almost another half a century, even with the increasingly widespread understanding of atmospheric pressure and vacuums, for a widely-adopted and practical atmospheric engine like Thomas Savery’s to appear? > The answer, I think, is what it almost always is: that inventors are simply extremely rare. People can have all the incentives, all the materials, all the mechanical skills, and even all the right general notions of how things work. As we’ve seen, even Savery himself was apparently inspired by the same ancient experiment as everyone else who worked on thermometers, weather-glasses, egg incubators, solar-activated fountains, and perpetual motion machines. But because people so rarely try to improve or invent things, the low-hanging fruit can be left on the tree for decades or even centuries.