D) Absorbing the ‘intoxicating plants’

To release the various beneficial aspects of the plants and become intoxicated through them to communicate with the gods and the dead relatives, different ways of proceeding, dating from ancient times, are known. Obviously, the one which particularly interests us, as regards our subject, is the fermentation of plants in liquids so as to obtain a sacred beverage. Unfortunately, the actual processes in Celtic times are very little known but are open to various hypotheses based on what is known about other ancient civilizations.