Let's relax with the conclusion of this most remarkable book of geological theory. This time, a plea to scientific advancement and nation-building in the form of an expedition to the Earth's interior, an outline of the voyage, and a glowing portrait of Captain Symmes and his genius. Well, at least he tried, I guess? 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" by John Cleves Symmes 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, https://www.boringbookspod.com.