The vase destroyed in this episode is identical to the one that is destroyed in The Night of the Torture Chamber (1965).
While seeking James West at the hospital, Artemus Gordon meets Madame Lafarge (listed as Maggie Lafarge in the credits). She is a caricature of Madame Defarge, a leading character in the Charles Dickens novel "A Tale of Two Cities". The knitting, the guillotine, and the play on the name by Maggie all refer to Madame Defarge.