Collections: Dawn of the Electrical Age (1600-1800)
The toy consists of a mahogany box containing four numbered
ebony chips. The chips can be removed and replaced in any
order.Each chip contains a hidden iron bar, situated parallel to
the face of the chip and each one oriented differently from the
The toy is missing its "key", shown in the illustration on the right. The key contains four paper disks which are mounted like compass needles and are free to rotate. To operate the puzzle, the host averts his eyes and invites a guest to rearrange the ebony chips in any order and close the case. The host then places the "key" on top of the still closed puzzle and reads the correct answer from the key, amazing his guests. What the guest can't see is a small iron bar attached to each disk inside the key that causes the disk to align with the numbered ebony chip in the puzzle. The magnetic attraction causes the iron bar to align with the chip, bringing the appropriate number to view in the window.
The mahogany box measures 10-3/4" x 2-3/4" Unsigned, but very similar to item number E71 described and illustrated on p. 445. of Public and Private Science, The King George III Collection, Morton and Weiss, London 1993.