First, a couple of gowns that might be worn by the characters in these books . . .
1860s skating costume
1866-1868 The Philadelphia Museum of Art
And something for Primrose to wear in the forthcoming Parasol Protectorate Abroad series.
1890-1895 The Victoria & Albert Museum
Some vintage picks for the Rack:
1914 Dinner Dress The Philadelphia Museum of Art
1925 Raymond C. Yard Christie’s
1938 Evening Suit Elsa Schiaparelli The Arizona Costume Institute; 1938-1939Suit Elsa Schiaparelli, The Metropolitan Museum of Art
1940 Elsa Schiaparelli The Metropolitan Museum of Art
1940 Schiaparelli ensemble; 1943 Sally Victor The Metropolitan Museum of Art
1945 Evening Gown Elizabeth Hawes Augusta Auctions
1954 Cocktail Dress Christian Dior The Chicago History Museum
1955 Norman Norell The Indianapolis Museum of Art
1958 Jacques Fath The McCord Museum
1959 Cristobal Balenciaga The Henry Ford Costume Collection
Joan on Mad Men c. early 1960s look
Retro Rack is also on facebook where I post additional images and fashion thoughts.