Introduction

For a very long time, light was rare. Homes were pretty dark at night and the street lights outside barely delivered better illumination. Once you stepped out of town where you lived, the only light you could count on was the one you brought with you. Which is why travellers around the world have told stories about surprising sources of illumination. They are a truly global phenomenon. Pick a culture in any part of the world, open up a book about the folklore there, and you're sure to find mention of them.