《明史·志·卷六十三》
仅仅往下挖几尺就是碉殉石，又往下挖全是泥沙，再往下挖全是黑色泥沙，再往下挖水泉涌出，刚刚挖掘就被淤塞，其深只有一丈二尺。
才下数尺为碙〈石句〉石，又下皆沙，又下尽黑沙，又下水泉涌出，甫挑即淤，止深丈二尺。
Just digging a few feet down is a碉殉 stone. Going further down is all silt, and further down is all black silt. Further down, the spring water gushes out, and it is blocked as soon as it is dug, and its depth is only one zhang and two feet.