Let’s continue with this sleepy theory about the Earth and how fish migrations absolutely, positively prove that it must be hollow. What other explanation could there be? None, says Symmes!   Help us stay ad-free and 100% listener-supported! Patreon: https://www.patreon.com/boringbookspod Buy Me a Coffee: https://www.buymeacoffee.com/d5kcMsW   Read “Symmes Theory of Concentric Spheres” at Project Gutenberg: https://www.gutenberg.org/ebooks/54329   Music: "Boring Books for Bedtime,” by Lee Rosevere, licensed under CC BY: https://leerosevere.bandcamp.com   If you'd like to suggest a copyright-free reading for soft-spoken relaxation to help you overcome insomnia, anxiety and other sleep issues, connect on our website, http://www.boringbookspod.com.