Philip Smith invented the 'lap-back' structure - allows front & rear boards to project backwards to half the width of the spine producing a single, continuous plane when the book is fully open. Allows an image or configuration to be created across both boards, virtually uninterrupted by the spine. Edges of the laps may be cut into a variety of shapes, interlocking if necessary, with the potential to make a book without any straight edges. As laps act to protect the spine, it need not be lined.
