What I know of this comes from the mind of the ancient one whose skin is the color of fine white ash. He wears only the hide of a leopard. He sits looking into the mirror of a pool of water. The mirror catches the blue-white light of a distant star in an indigo sky, shining down through the smoke hole of the conical hut.
The ancient one reads other things in the water, the intersection of purposes projected from another world with human lives. As he reads the patterns, he scores lines with his forefinger in the bed of fine powder at his feet.
There is a swirling in the water. A vortex opens at its center, turning very fast. Then the swirling reverses direction and the water gathers in a spout that spurts high into the air. From the hard spray, a new pattern emerges. The water moves in a way that water cannot move. Fourteen ridges appear, moving rapidly from the center, running to the edges of the pool. The ancient nods and notes the event in the dust, in his binary code of single and double lines.
12th century bronze head of a Yoruba king in the British Museum