The ancient Alchemist was depicted as a man, usually with a long beard, doing things in a great fireplace. Fire would be used to boil water. The water would turn into steam and ascend up the chimney. The four “elements” of Earth, Water, Fire and Air, were manipulated by the Alchemist to transform lead into gold. Modern thinkers don’t buy into this. To them this is nonsense.
This podcast is about a different interpretation of Alchemy. For that you will have to listen to the actual podcast.