wizard
" conjured up for those who consulted him a picture of their coming
fates, after the manner yet practised by the Caireen magicians, who,
however, substitute for the sphere a pool of ink held in the palm of a
boy's hand. This magic mirror may be seen preserved in the class of
Crystals (quartz) in the British Museum. Dr. Dee had very ancient
authority for such a mode of foreshowing the future, for Marbodus thus
transcribes the precepts of some antique magus, though giving the diadochus (simply mentioned by Pliny as resembling the beryl) for the
Crystal :—
" If e'er thou seek, where deep the rivers flow, To force the water-sprites the fates to show, Take the diadochus upon
thine hand ; No gem more potent o'er the fiendish band. Within its orb
to thine affrighted eyes Shall myriad shapes of summon'd demons rise.
But mark ! if brought in contact with a corse,. Forthwith the gem shall
lose its native force. Like to the beryl shows the wondrous stone, That
dreads the touch of one by death o'erthrown."