Incredible But True Incredible But True Human World History Makers Cities Of The World Art And Music Sporting Headlines Plant Life Fish, Amphibians, Reptiles Birds and Mammals Creepy Crawlies Marine Life Restless Earth Earth's Secrets Changing Weather Seas And Oceans Comparisons Amazing Structures Machines And Man World Of Inventions Travelling Around Mysterious Universe	Tidal Energy The power produced by the Earth's tides is enough to lift the entire world population 5km up in the air once every hour. Earth's tides   Previous: Back Book: Incredible But True Section: Incredible But True Chapter: Comparisons