Le Mystère des Cathédrales SweatshirtFulcanelli's Le Mystere des Cathedrales revealed that Gothic cathedrals are alchemical textbooks written in stone. Every gargoyle, rose window, and carved figure encodes stages of the Great Work for those with eyes to see. About This Design The mysterious Fulcanelli demonstrated that medieval cathedral builders embedded hermetic and alchemical symbolism throughout their architecture. Manly P. Hall frequently referenced this work when discussing the