This 2,000-Year-Old Chinese Device Detected Earthquakes Without Satellites! [rvFLfBQnHe7]

Imagine detecting an earthquake nearly 500 km (300 miles) away 2,000 years before modern technology! Discover how this incredible invention became the world's first known earthquake detector and why it still amazes scientists today. #AncientChina #Earthquake #History #AncientTechnology #AmazingFacts