The practice of sexual transmutation as couple (male-female), a technique known in Tantra and Alchemy. Arcanum refers to a hidden truth or law. A.Z.F. stands for A (agua, water), Z (azufre, sulfur), F (fuego, fire), and is thus: water + fire = consciousness. . Also, A (azoth = chemical element that refers to fire). A & Z are the first and last letters of the alphabet thus referring to the Alpha & Omega (beginning & end).