cephalomancy

Cephalomancy is a form of divination using a goat or donkey's head. Cephalomancy technically means "head divination" and therefore applies to any sort of divination using a skull or head. it covers two different methods: one was concerned with the shape of the skull, somewhat like extispicy or phrenology. The other, cephaleonomancy, involved heating a skull while reciting various phrases, often the names of criminal suspects. If the skull crackled or the jaw moved while a name was spoken, this was taken to identify the guilty party. (Cephaleonomancy literally means divination by a donkey's head, but it also applies to the same technique using a goat's skull.)
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Divination by boiling a head, usually that of a donkey