Empyreumatic flavour

It concerns the awful flavour of alcoholic beverages once they become distillates. The mucilaginous substances contained in those materials submitted to distillation store more heat than liquid substances; according to Higgins remarks, this heat increase gives rise to oil drawing combined with the acetic ether produced during the operation and create a compound that etches brass, corrodes and fills it up with the oxide of this poisonous metal. Consequently, the “empireuma” is a quadruple product made of acetic acid, ether, brass oxide and oil that dissolved in alcohol makes this liquid as mortal.

Font: L.S. Lenormand, L'Art du distillateur, Paris 1817.