Basil Valentine is the Anglicised version of the name Basilius Valentinus, ostensibly a 15th-century alchemist, possibly Canon of the Benedictine Priory of Saint Peter in Erfurt, Germany but more likely a pseudonym used by one or several 16th-century German authors.
"Frater Basilius Valentinus, monk of the Benedictine order and Hermetic philosopher": imaginary portrait in the frontispiece from Chymische Schrifften, 1717
The Peterskirche, Erfurt, as it appeared in 2007
Table of alchemical symbols, from an English translation of his Last Will and Testament, 1671
Illustration of the first key
Chloroethane, commonly known as ethyl chloride, is a chemical compound with chemical formula CH3CH2Cl, once widely used in producing tetraethyllead, a gasoline additive. It is a colorless, flammable gas or refrigerated liquid with a faintly sweet odor.
Bottle of compressed EtCl for anaesthesia