Most of the spells in the Han Dynasty came from the Zhou Rites in the pre-Qin period. It was said that there was a method called "Li’s official clapping ten times", that is, the ancient art of observing the sky could judge the evil spirits in the distance by ten kinds of weather.
There are five kinds of stingy in the last door of the ten styles, which are observing what happens. "Green gas is a sign of famine, red gas is a war and killing disaster, white gas is a mountain of dead people, black gas is a phenomenon of terror and fear, and yellow gas is…