Seven Small Inventions that Changed the World

Technology and engineering surround us. From HUGE things, like spaceships and skyscrapers, to much smaller things like the toaster in our kitchen, and the shoes on our feet. But all of these things only exist because of seven small inventions: the nail, the wheel, the spring, the magnet, the lens, the pump, and ... string. And each of these inventions has a fascinating story to tell.

Travel through centuries of history, through ancient Egypt, along the Silk Road, across the high seas, and e...