Helen Helmore and Vera Tassell operated a jigsaw puzzle club out of the Maids of Kent Craft Shop in Canterbury, England in the 1920/30s utilizing such revolutionary techniques as double cutting-deception. This involved cutting 3 sides of two pieces held one on top of the other, so that the wrong piece will appear to fit (temporarily) into the wrong place in the puzzle thereby preventing completion of the puzzle unless moved to the right place. Believe me, this technique worked brilliantly, especially in the sky section where there are several examples! Today, the same basic technique is called "2-way trick" and has given rise to a new genre of very challenging puzzles. Our collection also includes a 1930s American puzzle, Heaven and Earth Blending, in which entire sections were double cut on top of each other resulting in nearly 100 pieces being totally interchangeable (except for color) between two sections. Plywood, interlocking, color line cut. Artist: W. Smithers Broadhead.