EFFECT :
Performer and spectator each shuffle a pack of cards in
the dark. Performer selects a card from the spectator's pack and
vice versa. The cards are laid on the table beside the packs. The
lights are put on and the cards are found to be identical.


HOW IT'S DONE....
In his pocket the performer has a forcing pack to match
the two packs to be used openly. When the lights are turned off he
changes 79
the pack in his bands for the forcing pack and it is from this pack
that the spectator draws a card. He then exchanges the card he
draws from the spectator's pack for a card from the forcing pack,
slips this pack into his pocket and takes out the ordinary pack.
When the lights go on again all there is to be seen is the two
ordinary packs and the two similar cards.