Radio-Style System of Communication Via Magnetic Waves Demonstrated in…

After 13 miners were trapped in a coal mine in Sago, West Virginia, four years ago, rescuers didn't know where to look for survivors — they could have been anywhere between 11,000 and 13,000 feet from the entrance. Radio waves can't penetrate very far through rock, so there was no way to communicate with the miners. » 8/10/10 1:00am 8/10/10 1:00am