《太平广记·卷四百七十七·昆虫五》
父亲叫小男仆追寻他的足迹。出了房子数十步，到了古树的下面，看到一个洞，那根线就延伸到里面去了。
明日，女告父，命僮逐其迹，出舍数十步，至古木下，得一穴而绳贯其中。
Her father asked the young servant to follow the trail. After tracing it for dozens of paces outside the house, they came to an ancient tree. They saw a hole under the tree and the string went down into it.