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.