About a third of the way through this book, John Edward Huth asks why it is cold in the winter and hot in the summer. This is not a trick question and I will give you a clue: the answer involves the sun. But does it get warmer in summer because the earth comes closer to the sun? Twenty-one out of twenty-three Harvard graduates and faculty members thought so, and if you agree with them then, like them, you are wrong. The sun is actually a little further from earth during the summer, but temperatures rise because that is also when the sun moves directly overhead. So why don’t Harvard’s finest know this? The point Huth extracts from this is that the sun, like so much else, has lost its meaning for us, that its position in the sky is no longer of importance to us. It was not always so.

If you want to get from A to B, whether you are travelling from Angel to Bank or Aberystwyth to Bognor Regis, the chances are you will find your route by peering into a phone or computer screen, or being guided by a satellite out in space. If the system