In Henry J. Wehman’s The Mystery of Love, Courtship and Marriage Explained (1890) [https://archive.org/details/TheMysteryOfLoveCourtshipAndMarriageExplained/page/n33/mode/2up] there are charts of secret messages Victorian flirters could send with fans, parasols, gloves, and handkerchiefs. Whether the handkerchief codes were ever in use (or mainly used