Patented by T. Graham 1934, made by the Embossing Company of Albany 1937.
(cardboard box 4.4" x 4.4" x 5/8" inches and 13 wood pieces;
Hordern's book dates the blue version above as made in 1937, and gives a solution)
Slide the pieces, avoiding the two forbidden squares, to get go from a start position to a final position; here are problems 1, 2, and 3 from the directions that were sold with it:
