"As they climbed the wooded trail to the top of a ridge from where they could see houses down in the valley across from them, the four young hikers had reached the cave in the Ohio hills. Shining a flashlight onto the bottom of the cave's mountainous inner wall, they found evidence of some digging. Their curiosity spurred them on to dig there too. Soon, the ground gave up the shape of a box. Loosening its earthen grip, the four adventurers pulled...