In Shakespeare's times, the movement of the heavenly bodies, their precise and their predictable courses, was taken quite seriously. Any irregularity in the heavens was usually interpreted as an omen of "unnatural" things to come. Hence, eclipses, comets, and other celestial aberrations, fascinated but unnerved the people.
The seasons of the year were attributed special qualities, in continuous circular repetitive movement. Here, however, they are represented in a rectangle.
Choler(pronounced just like collar) distinctly means anger, just as sanguine clearly means cheerful, agreeable, and pleasant in Shakespeare's writing. Some people actually still believe the four humors - you may recall young Victor Frankenstein did so initially. "Sensible" people such as Edmund, in King Lear, dismissed a different popular belief, astrology, a remnant of medieval times, as utter nonsense. Many in Shakespeare's audience would have disagreed with Edmund.
This is a contemporary, somewhat distorted, diagram of the four humors.