《明史·志·卷六》
这一年，胡惟庸家的水井中长出石笋，除掉它，石笋又多次从旁边生出来。
是岁，胡惟庸井中生石笋，去之，笋复旁出者三。
In this year, in the well of Hu Weiyong's family, a stalagmite grew out of it, which, after being removed, grew out again from the side several times.