Instructions
Look for the original Windsor design, which was characterized by a back frame that was bent into a hoop. The legs were splayed slightly with pegs inserted directly into the seat of the chair.
Learn about other Windsor designs, including a rounded hoop back, horizontal pieces of wood across the spindles, a comb-shaped back and flat spindles on the back.
Look at images of antique Windsor rocking chairs in order to best identify them in person. There are images online on websites, such as DesignBoom.com, or in books, such as "The Rocker: An American Design Tradition" by Bernice Steinbaum, which contains pictures of American variations on the Windsor. Books on antique rocking chairs can be bought at book stores or online or borrowed from your local library.
Search for antique Windsor rocking chairs that are painted green or black. These were the first colors the chairs were painted. Each color indicates the chair is likely an antique Windsor.
Look for Windsor chairs that are weathered and have been exposed to the elements. As the first Windsor chairs were commonly placed in the garden, remaining chairs are quite worn.