I believe that Edwards is not overly reliable. The Footed Prisms or Footed Prism Panels is Brockwitz, late 1920s, early 1930s, "Century of Carnival Glass," Thistlewood and Thistlewood
I think Keith is correct with Smooth Panels, although the barely flared top looks quite unusual. It seems quite common for Imperial vases to be only partially irridised. Personally, I think it spoils them.