Cardsharping, said the American Academy of Political and Social Sciences in 1950, “carries a greater stigma than the seduction of a friend’s wife.” Nevertheless, it has enjoyed a long, vigorous life. Here are two tools of the cheater’s trade.

Jacob’s Ladder Holdout

The hand below is equipped with an 1890s device that could produce a good card or remove a poor one, unbelievably without the other players noticing.

Marked Cards

These “readers” revealed their secrets though subtle differences of detail and shading in the cherubs.