There is an abandoned Wujin Alley in Puningfang, Chang'an City. An old locust tree grew up in the middle of the alley.
Four years ago, on June 15th, purple thunder fell and split the crown of the locust tree. From then on, the pavilions on the west side were like canopies, and the east side was like cliffs. It was like the heaven and earth divided into yin and yang, which became a strange thing in the capital.