Richard Kaufman, in Steel and Silver reports that Dai Vernon told him the idea of using the thumb to flick or kick a coin secretly across the table was used by T. Nelson Downs in the 1930s, though never published by him. He used it in the context of an Unlimited Coinage of Silver routine. A Larry Jennings trick in the May 1970 issue of Genii (Vol. 34 No. 9, p. 408) has been suggested as the first instance of the idea in print, although the connection seems a bit tenuous. Jennings used his thumb to kick a cup off the table and into his lap, under cover of a silk. This is inward, propelled lapping, rather than a sidewise, vanish-loading technique, although it may be argued that the mechanic is the same, no matter what the final destination of the object. Two years later, Mike Rogers published a similar idea, “Coin Kick & Card Change”. Rogers started with a coin vanish using a thumb flick to lap or sleeve, which Edward Marlo had shown him. Rogers applied the same lapping idea to a card change. See the May 1972 issue of Kabbala, Vol. 1 No. 9, p. 68.