Access over 70+ Ad-Free episodes of Calm History by becoming a Silk+ Member (FREE for a limited time!) and enjoy over 600 total episodes from these relaxing podcasts: Calm History (70+ episodes) Sleep Whispers (430+ episodes) ASMR Sleep Station (50+ episodes) 1 & 8-Hour Nature Sounds (50+ episodes) 1 & 8-Hour Background Sounds (30 episodes) Counselor Curt ASMR (20+ episodes) ASMR University (10 … Continue reading #32 | History of Coal [300 BC – 2024 AD]: Geology, Discovery, Industrial Revolution, Mining Dangers, Miner Strikes, & Many Curious Facts