A witch at her cauldron, standing in a magic circle, surrounded by demons. A grimoire (book of magick spells) can be seen in the right corner, and a goat, representing the Devil, can be seen behind her. Etching by Jan van de Velde II, 1626. Source: Wellcome Library
“Cabala, speculum artis et naturae, in alchymia” by Stephan Michelspacher, 1616, is a short pamphlet about hidden secrets in 4 works of art. The book claims that only masters of alchemy will fully understand them, but gives hints to their meanings relating to: chemistry, astrology, philosophy, art, virtues, and the natural elements.