World?s Greatest Prediction Chest. Columbus: Bob Mason/Arturo, ca. 1972. Handsomely crafted hardwood chest locked in a clear Plexiglas box contains a prediction of a forthcoming newspaper headline. Exceedingly bold and ingenious method allows the prediction to be loaded in full view of the audience. Includes key box, prediction chest, Plexiglas box, locks, and keys. The larger wooden box 8 x 6 x 6?. Hallmarked. With the original packing cartons, one bearing a handwritten note from inventor Bob Mason. Rare.