In Chang’an there was a fortune teller of great skill. He could say what hour rain would fall on a given day and how much, and word of it traveled as far as the bottom of the river.
The dragon king of the Jing River heard it and was angry. Making rain was his own work, so he took human form and went to the fortune teller’s shop.
The fortune teller wrote out the next day’s rain for him. The dragon deliberately altered the hour and the amount, and that made it a breach of Heaven’s order.