V.I.T.R.I.O.L (Masonic/Alchemical Motto)
In chemistry, vitriol is iron or copper sulfate salts and their derivative, sulfuric acid. The name comes from the Latin for "glassy," after the resemblance of iron sulfate to shards of green glass. Vitriol is symbolized alchemically as the "green lion," a poisonous substance that appears when metal is degraded by acid. Sulfuric acid, or oil of vitriol, was used in the synthesis of the lapis philosophorum- the Philosopher's Stone. One unique peoperty of sulfuric acid is the dissolution of metals- all except for gold, on which it has no effect.

The alchemical motto for vitriol is "Visita Interiora Terrae Rectificando Invenies Occultum Lapidem," "Visit the interior of the earth and rectifying (purifying) you will find the hidden stone." The motto originated in L'Azoth des Philosophes by the 15th Century alchemist Basilius Valentinus.