In this episode where Uncle Arthur conjures up Napoleon Bonaparte by mistake, he also threatens to turn Darrin into a mini Eiffel Tower. Napoleon replies "I'd like to see that", but in fact he could not know what the Eiffel Tower was as it only began construction 66 years after his death.
Napoleon (magically brought into the present by mistake, by Uncle Arthur), is said to have requested Crêpes Suzette, despite the fact that they weren't invented until long after his death. Napoleon also mentions "Napoleon Brandy", a term that did not come into use until after his passing.