The long-and-short-page principle used in the Blow Book and adapted to playing cards was applied in the last half of the twentieth century to a variety of paper pads gimmicked to force a word, number or image. Richard Mark was among the earliest, perhaps the first, to do this, using a number of loose pages fastened together at one end by a clip; see “Symbolysis” in Mark's MindBending Magic, 1979, p. 5. later reprinted in MindWarp, 2000, p. 35.
Various special forcing pads relying on the long-short principle have since been devised by a number of magicians. In the early 1980s, the manufacture of specially gimmicked pads to force items began and has continued, with forcing pads being marketed by Ton Onosaka, Scott Creasey, Chris Jones, Brett Barry and others.
Also see: Svengali Deck