A five-sided head-dress of fine linen, meant to represent the five senses, and worn as a defence against demons in the act of conjuration. It is also called Solomon's Seal (signum Salamonis). A pentacle was extended by the magician towards the spirits when they proved contumacious.
And on her head, lest spirits should invade, A pentacle, for more assurance, laid.
The Holy Pentacles numbered forty-four, of which seven were consecrated to each of the planets Saturn, Jupiter, Mars, and the Sun: five to both Venus and Mercury: and six to the Moon. The divers figures were enclosed in a double circle, containing the name of God in Hebrew, and other mystical words.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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