Modern Magic: A Practical Treatise on the Art of Conjuring

The secret lies in the simple arithmetical fact, that if you add an odd number to an even number the result will be odd; if you add an odd number to an odd number the result will be even. You have only to take care, therefore, that the number you yourself add, whether large or small, shall always be odd. TO CHANGE A FLORIN INTO A PENNY, BACK AGAIN, AND THEN TO PASS THE SAME INVISIBLY INTO THE POCKET OF THE OWNER.--This is a trick of genuine sleight-of-hand, and will test your expertness in two or three different passes. Having beforehand palmed a penny in your right hand, you borrow from one of the company a florin (or half-crown), requesting the owner to mark it in such manner that he may be able to identify it. Make him stand up facing you, your own right side and his left being towards the audience. Taking the marked florin between the fingers and thumb of the right hand (the back of which, from your position, will be toward the spectators), you ask him whether he is nervous, whether he can hold fast, and so on. On receiving satisfactory replies, you state that you are about to put him to the test, and request him to hold out his right hand, telling him that you are about to count three, and that at the word “three” you will drop the florin into his hand, which he is to close tightly upon it. You accordingly count, “One! two! three!” each time making a motion as of dropping the florin into his hand, and at the word “three” actually do drop it, when he closes his hand upon it, as directed; but you are not satisfied.