_A trick with cards; uniting the double Advantage of being very easy
and infallible, it being on a little numerical Combination._
Desire some person in the company to chuse, at his will, three cards
out of a piquet pack, observing to him, that the ace is to be counted
for 11 points, the court cards 10, and the other cards according to the
points they mark.
When he has made his choice, desire him to lay on the table his three
cards separately, and to put upon each parcel as many cards as wanting
to make up 15 points; that is to say, if the first card should be a
nine, there must be added six cards over; if the second a ten, five
cards; and if the third a knave, five cards likewise; this will make
nineteen cards employed; consequently there will remain thirteen, which
you are to ask for; and pretending to examine them, you must count them
in order to be certain of the number that is left; then in your mind
add sixteen to the remaining number, and you will have twenty-nine,
number of the points that the three chosen cards under the parcels
contain.