Picture, if you can, a world without glass. There would be no microscopes or telescopes, no sciences of microbiology or astronomy. People with poor vision would grope in the shadows, and planes, cars, and even electricity probably wouldn't exist. Artists would draw without the benefit of three-dimensional perspective, and ships would still be steered by what stars navigators could see through the naked eye. In Glass: A World History , Alan Macfarlane...