from the Oxford English Dictionary

catoptromancy (kato/ptromænsi. f. Gr. kátoptron [mirror] + manteía [divination]; see -mancy). Divination by means of a mirror.

• 1613 Purchas Pilgr. I. iv. v. 310 Catoptromancie received those resemblances in cleare glasses.
• A. 1693 Urquhart Rabelais iii. xxv. 207 Catoptromancy..held in such account by the Emperor Didius Julianus.
• 1758 Ann. Reg., Charac. 275/2 He..understands all the mysteries of..catoptromanchy, he having a magical glass to be consulted upon some extraordinary occasions.
• 1855 Smedley Occult. Sci. 321 Catoptromancy, a species of divination by the mirror.