[Card Games]
Take a pack of cards, select from it the spades and the hearts, rejecting only the kings. Arrange each of these suits in sequence,—ace, 2, 3, … 9, 10, Knave, Queen,—the ace being at the back, the queen at the front. Put the hearts on the table in a pile, backs up. Deal off the spades one by one into two piles, turning each card over and laying it down, face up. The cards in this dealing are, of course, alternately placed on the left hand and the right hand piles. But when you come to the last card, which will be the queen, instead of putting it down on the pile where it would regularly go, you put it down on the table, face up, to form the first card of a new pile. In the place where the queen would have gone had you proceeded regularly, now put instead the top card of the pile of hearts, which is the ace, turning it face up. Now cover the pile upon which you have just laid this card, with the other pile of six spades, and take up the combined pile into your hand, faces down. Repeat this operation: that is, deal out the cards you hold in your hands into two piles, until you come to the last card which will be the knave, which you place on the queen, as the second card of that pile, and in place of the knave you put on the second pile, the top card of the pile of hearts, which will be the two. You then cover this pile with the other pile of six, and take up the combined pile, as before. Do this over and over until you have done it twelve times in all, when you will hold all the hearts in your hand, and all the spades will lie in a pile on the table. Now I say that there is a singular relation between the arrangement of the spades and that of the hearts, so that when you have once remarked the secret of it, by examining the spades which you hold in your hand, you can readily tell off the hearts in the order in which they lie on the table. What I ask you to do is, preserving their order, to spread out the spades and the hearts on the table, and try if you can see what this relation between the two orders is.
Take a pack of cards, and arrange them in sequence, proceeding from back to face, as follows:—Spades: ace, 2, 3, … 10, Knave, Queen, King. Diamonds: ace, 2, 3, … 10, Knave, Queen, King. Clubs: ace, 2, … Queen, King. Hearts: ace, 2, … Knave, Queen, King. Thus, the ace of spades will be at the back, and the king of hearts at the face of the pack. Take the pack in your hand, face down, and deal the cards out singly, into five piles, in regular rotation, turning each card face up as you lay it down. Take up the third pile and lay it face up on the first, so as to make one pile of the two. Place this combined pile on the last pile but one, so as to make one pile of them. Take up this still larger pile and lay it on the first pile, so as to combine these. Take up this pile and lay it on the last of the original piles, so as to unite the whole pack. Take up the pack into your hand, faces down, and deal the cards out one by one into six piles in regular rotation, turning them up as you lay them down. Place the fifth pile on the fourth, this united pile on the third, this pile on the second, this on the first, and this again on the last, so as to reunite the whole pack, spread the cards out in four rows, of thirteen in a row, as follows, where the numbers show the places of the cards in the pack before they are spread out.
1 2 3 4 5 6 7 8 9 10 11 12 13
14 15 16 17 18 19 20 21 22 23 24 25 26
27 28 29 30 31 32 33 34 35 36 37 38 39
40 41 42 43 44 45 46 47 48 49 50 51 52
You will now find a singular relation between a card and a certain other, in respect to their suits and numbers in the suits, their rows and places in the rows. Try to discover that relation.
Take a pack of 52 cards, and select all the plain cards of three suits. Arrange them in order from 1 to 10, one suit after another, in a pack, beginning at the back with the ace, and a ten at the face of the pack. Then you have thirty cards, and the second suit you can conceive as numbered from 11 to 20, and the third suit from 21 to 30. Now hold the pack in your hand with backs up, and deal them out into a number of piles which may be either 2, 3, 5, 6, 10, or 15. The cards are to be dealt out singly, and each card is to be turned up as it is laid down on the table and you are to deal them out to the different piles in regular rotation. When the cards are all dealt out, you place the first pile on the second, and you place that combined pile on the third, you place that combined pile on the fourth, and so on until you have united the whole pack. Now, I wish to know whether you can find a rule or general statement by which, when you know how many piles the cards have been dealt out into, you can tell what their order will be beginning at the back of the pack, and proceeding to the face. Also, what will be the effect of dealing them out twice or three times.
When you have ascertained the rule asked for in the last problem, take the cards in their original order and deal them out into eight piles; as eight does not divide thirty, it will follow that the last two piles will have each one card fewer than the others. Put the seventh pile on the sixth, put this combined pile on the fifth, put this combined pile on the fourth, put this combined pile on the third, put this combined pile on the second, put this combined pile on the first, and this combined pile on the remaining pile. Now, you will find that the rule which you have already discovered in regard to the order of the cards, holds good in this case. This is because you pick up the piles in this particular order. Now I want to know if you can tell