Canon's Yeoman's Tale

I thought alchemy was about making potions, but aren't these guys just magicians? Tricking priests into thinking they can turn anything into silver doesn't make me think of alchemy... While the Yeoman is introducing them, the Canon even tries to sneak away because he is worried the Yeoman is sharing too many of his secrets. They remind me more of con artists than potion makers :( I was really hoping they were mixing up cool potions. I was especially convinced that these guys were phonies when he sells his secret for 40 pounds and then disappears. Slightly disappointed, but they are still very entertaining and an unexpected surprise. 

https://i.ytimg.com/vi/VlRXDwsJ9zE/maxresdefault.jpg