The Ten Duplicates

Select any twenty cards; let any person shuffle them; lay them by

pairs on the board, without looking at them. You next desire several

persons, (as many persons as there are pairs on the table,) each to

look at different pairs and remember what cards compose them. You then

take up all the cards in the order they lay, and replace them with

their faces uppermost on the table, according to the order of the

letters in the ollowing words:



M U T U S

1 2 3 4 5

D E D I T

6 7 8 9 10

N O M E N

11 12 13 14 15

C O C I S

16 17 18 19 20



(These words convey no meaning.)--You will observe, that they contain

ten letters repeated, or two of each sort. You therefore ask each

person which row or rows the cards he looked at are in; if he say the

first, you know they must be the second and fourth, there being two

letters of a sort (two U's) in that row; if he say the second and

fourth, they must be the ninth and nineteenth, (two I's,) and so of

the rest. This amusement, which is very simple, and requires very

little practice, will be found to excite, in those who are

unacquainted with the key, the greatest astonishment.



The readiest way is to have a fac-simile of the key drawn on a card,

to which you refer.