Divining board or rubbing board oracle

Divining or rubbing board oracle called euwa (iwa) in Zande, comprised of two discs of hard wood, one with foot rest and two legs on underside, other has central projection on top, Azande, South West Sudan, Africa, 1880-1910

Known as euwa or iwa in Zande, this board was used for divining or answering questions relating to life and death, guilt or innocence, health or disease. The diviner placed it on the ground and held it in position using their foot. Both parts were first wetted before the upper disc, called the Waled (son) was rubbed over the lower section, the Um (mother). The answer to a question asked of the oracle depended on when the upper disc stopped moving due to the friction.