Another piece of art... and a very famous one too
The Magic Circle- John William Waterhouse
"A magic circle was cast to purify and create a perimeter of space wherein evil magic could not enter. Goddesses and good spirits were invited into the circle, which sometimes had powerful, protective stones placed at North, South, East, and West points. Each point was associated with the Four Elements. North was the most powerful direction. It represented the element of Earth, the celestial bodies revolving around the North Star, and encompassed all secrets, darkness, and the unknown. South was the element of Fire and therefore associated with the sun. This point signified the meeting of East and West - intuition, insight, reason, and logic - and the channeling of the powers of intellect, clairvoyance, and nature. East was the direction for the element of Air, symbolizing clarity, spiritual awareness, and mysticism. West represented imagination and inspiration, as well as emotions and reason. The circle itself was a mark of infinity and eternity.

A witch would cast a magic circle by turning clockwise, beginning at East, following the revolution of the sun. The magic circle was drawn with either a a magic wand or an anthame (a black-handled ceremonial dagger). A charm or spell was recited as the witch cast the circle, asking the presence of friendly or helpful spirits to attend." - Witches (1999), Lori Eisenkraft