INTRODUCTION.	19
	is to counteract the poison of the viper : you will there­fore find engraved upon it the figure of a man holding a viper, the virtue of the stone being thus denoted by the figure that it presents. But if the engraving should repre­sent Ophiuchus, a constellation possessing the power of resisting poisons, then by knowing the constellation you will recognise the virtue of the stone: and furthermore its efficacy will be doubled through the potency of the en­graving upon it. And this rule holds good for all the other gems." Eagiel lays down that " a Earn, or a bearded man's head (Ammon), on Sapphire, defends from many infirmities, from poison, and from oppression. A Hoopoe with the herb dragon in front, upon Beryl, hath power to summon the water-spirits, and to force them to speak. It will also call up the dead of your acquaintance, and oblige them to respond to your questions." Again Chael has : " Man with long face and beard, his eyebrows raised, sitting behind a plough, and holding up a fox and a vulture, with four men lying upon his neck—such a gem, if placed under your head when sleeping, makes you dream of treasure and of the right manner to find out the same." (The sigil thus curiously described is the favourite Roman type, the " Quattuor Tempora," the Year attended by the Four Seasons, his children.) " Man seated and a woman standing before him with her hair hanging down loose to her loins, the man looking upwards—this cut on Carnelian hath the virtue that whoever is touched there­with shall be led to do the owner's will immediately" (Hercules and Iole). "Man with a wand in his hand, seated upon an eagle (Jupiter), engraved on Hephaestite