Modern Magic: A Practical Treatise on the Art of Conjuring

A moderate degree of practice will make the student so proficient that even a person acquainted with the secret of forcing will have to be very wide-awake in order not to take the desired card. You will, however, sometimes find a person, suspecting your design and wishing to embarrass you, suddenly jerk his hand away from the card which he was apparently about to take, and draw another from a different part of the pack. In the great majority of tricks this is of little consequence, inasmuch as there are numerous ways (which will be hereafter explained) of ascertaining what the drawn card was; but there are some illusions which depend upon the drawer taking a card similar in suit and number to one already prepared elsewhere for the purpose of the trick. In this case it is, of course, absolutely necessary that the card drawn should be the right one; and as even the most accomplished performer cannot always be certain of forcing a single card, another expedient must be used in order to ensure success. This is made absolutely certain by the use of what is called a “forcing pack”--i.e., a pack in which all the cards are alike. Thus, if the knave of hearts is the card to be drawn, the whole pack will consist of knaves of hearts, and the drawer may therefore do his utmost to exercise a free choice, but the card which he draws will certainly be the knave of hearts, and no other. Where more than one card is to be drawn, as, for instance, in the well-known trick of the “rising cards,” the pack may consist, instead of similar cards throughout, of groups of two or more particular cards. Thus, one third may be knaves of hearts, one third aces of diamonds, and the remaining third sevens of clubs--the cards of each kind being together. With the aid of such a pack, it will require very little skill to ensure one of each sort being drawn.