throw one's cap over the windmill

Probably a calque of French jeter son bonnet par-dessus les moulins . Widely reported as deriving from a passage in the novel Don Quixote in which the titular character throws his cap over a windmill that he has mistaken for a giant, as a challenge. However, no such passage exists in the book.

• "Awfully commercial, women nowadays. Our grandmothers threw their caps over the mills, of course, but, by Jove, their granddaughters only throw their caps over mills that can raise the wind for them."
• "Even Catherine’s own mother scandalized her daughter by succumbing to the contagion of the place, and “throwing her cap over the windmill,” as the French have it."
• "Besides, Suzanne had already thrown her bonnet over the windmill."

• tilt at windmills