All the years that I was growing up, there was a large boulder in our cellar, sitting in the middle of the floor. The story was that the back wall of the foundation fell in while the concrete was being placed. The boulder fell into the excavation and was left there. Sixty years later, after all eight of us had grown up and the house had been sold, we learned from a contractor that, when he dug up the cellar floor, he discovered a box of "old dynamite" in the earth underneath the concrete.