Aspidomancy is a little known form of divination practiced in the Indies. It was first described by the 17th century writer Pierre De Lancre.
The diviner or sorcerer draws a circle in which he positions himself on a buckler (sheild) where he recites certain conjurations.
He enters a trance and then falls into ecstasy.
When he comes out he can tell his clients things which they want to know, or which the devil revealed to him. A.G.H.