Sassywood

"The person who is designated as guilty of the crime of witchcraft is arrested by the soldier king, and condemned to the ordeal of sassy-wood. The bark of the sassy-wood is powerfully narcotic, and a strong decoction of this the person condemned is forced to drink; and after he has drank it, he walks to and fro, exclaiming "Am I a witch," "am I a witch?" while one of his executioners walks behind him replying "You are a witch, you are a witch;" and this continues until he either throws off from his stomach the poison, when he is pronounced innocent, or it operates as a cathartic, when he is declared guilty, and compelled to take more of the decoction, and is subjected to other cruelties, which cause his speedy death. […] This ordeal by sassy-wood is one of the most prevalent and cruel of African superstitions, and is practised among nearly if not all the tribes of Africa."

"This man, being informed of his sentence, pleaded innocence, and said he himself would drink Sasswood water to prove it. His friends urged him to confess, as his brother, the king, said he had no ill will against him, and did not wish him to drink the Sasswood, unless it was his own pleasure to do so. He still, however, persisted in his wish to make the trial. Four pieces of the Sasswood tree, each about the size of a finger nail, were then prepared for him; […]"