Hero of Alexandria described a remarkable coin-operated dispensing mechanism. The system relied on gravity, levers, and carefully arranged components. Water flowed until the coin slipped away and the mechanism https://music.amazon.es/podcasts/69d3b9a8-ce50-4beb-8cef-e2712da6057e/episodes/a76ffe28-6efc-4ae7-a23f-f87f572fdab7/e39life