Oswald Rae first suggested the effect of making a chosen card appear between two panes of glass. See “A Transparent Affair” in his book Between Ourselves, 1926, p. 19. Rae gives two methods. Both relied on holding the card behind both panes, which fact couldn't be discerned by the audience.

Roughly ten years later Jack Hughes came up with a gimmicked mechanical frame that lodged the card genuinely between the two sheets of glass. First marketed by Davenport's in London, this method eventually became a standard dealers' item. For further details, see Bart Whaley's Encyclopedic Dictionary of Magic, 1989, p. 683.