What is bird divination?

"Bu" can be roughly divided into Mi Bu, Gui Bu, Bird Bu, Hand Bu, Zi Bu, Kong Ming Bu and Qian Bu.

The soothsayer of bird divination first explains the reason and what he wants to ask, and the soothsayer puts the bird in the cage. After lowering his head and muttering a few words to the bird, the bird crossed the bridge, opened the door of the divination room with its mouth, took out a divination book and gave it to the fortune teller.

This should be an ancient witchcraft divination.