Original Massey Duplex Slate: circa 1950

This may be the best of all slate effects. You take a small slate (which can be handled by the spectator) and show it is blank on both sides. You then wrap it in paper and hand it to she spectator. When it is unwrapped there is spirit  writing on both sides of the slate!  Massey was a genius and this was one of his most clever effects. The slate is 5.5 by 4.5 inches. Perfect operating condition. With a copy of instructions.