Our readers explain that spirit (or bubble) levels indicate the direction of Earth's gravitational pull, though local ...

Although inequality may well be problematic for these conventional reasons, The Spirit Level tells us that it’s mainly bad because it makes status differences more extreme and salient and thus ...

First up is the iPhone's easy-to-miss spirit level trick. It'll very helpfully let you know when an object is level with the ground. And if it isn't, you'll be shown how many degrees it's off by.