TRICKS WITH DOMINOES AND DICE.
TO ARRANGE A ROW OF DOMINOES FACE DOWNWARDS ON THE TABLE, AND
ON RETURNING TO THE ROOM TO TURN UP A DOMINO WHOSE POINTS SHALL
INDICATE HOW MANY HAVE BEEN MOVED IN YOUR ABSENCE.--This is a capital
drawing-room feat. You place a row of twenty dominoes face downwards
upon the table, avoiding as far as possible the appearance of any
special arrangement, but nevertheless taking care that the points of
the first domino (commencing from the left) shall amount to twelve,
the points of the second to eleven, and so on, each decreasing by one
point till you reach the thirteenth, which will be the double-blank.
The points of the remaining seven are a matter of indifference. You now
propose to give the company a specimen of your powers of clairvoyance,
and for that purpose leave the room, first requesting the company
to remove during your absence any number of dominoes (not exceeding
twelve) from the right to the left hand of the row, in other respects
retaining their order. On your return you advance to the table, and
address the company to the following effect: “Ladies and gentlemen,
as I have already told you, I have the privilege of possessing the
clairvoyant faculty, and I am about to give you a specimen of my
powers. Now it would seem at first sight sufficiently surprising that
I should be able merely to tell you the number of dominoes which
have been moved in my absence, but that might be easily effected by
confederacy, or many other very simple expedients. I propose to do
much more than this, and to show you not only that I know the number
that you have just displaced, but that I can read the dominoes before
you as readily in their present position as though they were lying
face upwards. For instance, this domino” (touching one of the row with
your finger or wand) “represents the number which have been moved in
my absence. Will some one please to say what that number was?” The
answer is, we will suppose, “Seven.” “Seven,” you repeat, turning over
the domino you have touched. “You see that I was right. Would you
like me to name some more? They are all equally easy. This, let me
see--yes, this is a two; this is a nine; this is a double-six; this is
a double-blank;” turning over each domino to show that you have named
it right.
This feat, which appears perfectly miraculous to the uninitiated, is
performed by the simplest possible means. All that you have to do is to
count secretly the row of dominoes as far as the thirteenth from the
left-hand end, or (which is the same thing) the eighth from the right
hand end, the points of which will invariably be the same as the number
moved from the right to the left of the row. You do not know, until the
domino is turned up, what that number actually was, but you must by no
means let the audience suspect this. You must boldly assume to know
the number, and from that knowledge, aided by some clairvoyant faculty,
to have selected a domino whose points shall represent that number.
Thus, having selected the proper domino, you call upon the audience
to state the number moved, after which the turning up of the selected
domino is regarded by the audience merely as a proof that you were
correct in the previous knowledge for which they, without the smallest
foundation, give you credit. After this domino has been turned up, it
is easy, knowing the original order of the thirteen of which it forms
one, to name two or three on either side of it. In most instances you
will only know the total figure of a given domino, as two or three
different combination of points will give the same total. (Thus a total
of seven may be represented by either six and one, five and two, or
four and three.) But there are two or three dominoes of which, if you
know the total, you know the points also. Thus a total “twelve” must be
always “double-six,” a “blank” always “double-blank,” a “one” always
“blank one.” By naming one or two of these, as if hap-hazard, you will
prevent the audience suspecting, as they otherwise might, that your
knowledge is limited to the _total_ of each domino.
It is obvious that this is a trick which cannot be repeated, as
the necessary rearrangement of the dominoes would at once attract
attention. You may, however, volunteer to repeat it in a still more
surprising form, really performing in its place the trick next
following, one of the best, though also one of the simplest, in the
whole range of the magic art.
TO ALLOW ANY PERSON IN YOUR ABSENCE TO ARRANGE THE DOMINOES IN A ROW,
FACE DOWNWARDS, AND ON YOUR RETURN TO NAME BLINDFOLD, OR WITHOUT
ENTERING THE ROOM, THE END NUMBERS OF THE ROW.--You invite the audience
to select any one of their number to arrange the whole of the dominoes
face downwards upon the table. This he may do in any manner he pleases,
the only restriction being that he is to arrange them after the fashion
of the _game_ of dominoes--viz., so that a six shall be coupled with
a six, and a four with a four, and so on. While he does this, you
leave the room, and, on being recalled, you at once pronounce, either
blindfold, or (if the audience prefer it) without even entering the
room, that the extreme end numbers of the row are six and five, five
and two, etc., as the case may be.
This seeming marvel depends upon a very simple principle. It will be
found by experiment that a complete set of dominoes, arranged in a
row according to domino rules (_i.e._, like numbers together), will
invariably have the same number at each end. Thus if the final number
at one end of the row be five, that at the opposite end will be five
also, and so on; so that the twenty-eight dominoes, arranged as above,
form numerically an endless chain, or circle. If this circle be broken
by the removal of any domino, the numbers on either side of the gap
thus made will be the same as those of the missing domino. Thus, if
you take away a “five-three,” the chain thus broken will terminate at
one end with a five, and at the other with a three. This is the whole
secret of the trick: the performer secretly abstracts one domino, say
the “five-three;” this renders it a matter of certainty that the row to
be formed with the remaining dominoes will terminate with a five at the
one end and a three at the other, and so on with any other domino of
two unequal numbers.
The domino abstracted must not be a “double,” or the trick will fail.
A little consideration will show why this is the case. The removal of
a double from the endless chain we have mentioned produces no break
in the chain, as the numbers on each side of the gap, being alike,
will coalesce; and a row formed with the remaining dominoes under such
conditions may be made to terminate in any number, such number being,
however, alike at either end. A domino of two different numbers, on the
other hand, being removed, “forces,” so to speak, the series made with
the remainder to terminate with those particular numbers.
[Illustration: FIG. 116.]
TO CHANGE, INVISIBLY, THE NUMBERS SHOWN ON EITHER FACE OF A PAIR OF
DICE.--Take a pair of ordinary dice, and so place them between the
first finger and thumb of the right hand (_see_ Fig. 116), that the
uppermost shall show the “one,” and the lowermost the “three” point,
while the “one” point of the latter and the “three” point of the former
are at right angles to those first named, and concealed by the ball
of the thumb. (The enlargement at _a_ in the figure shows clearly the
proper position.) Ask someone to name aloud the points which are in
sight, and to state particularly, for the information of the company,
which point is uppermost. This having been satisfactorily ascertained,
you announce that you are able, by simply passing a finger over the
faces of the dice, to make the points change places. So saying, gently
rub the exposed faces of the dice with the forefinger of the left hand,
and, on again removing the finger, the points are found to have changed
places, the “three” being now uppermost, and the “one” undermost. This
effect is produced by a slight movement of the thumb and finger of the
right hand in the act of bringing the hands together, the thumb being
moved slightly forward, and the finger slightly back. This causes the
two dice to make a quarter-turn vertically on their own axis, bringing
into view the side which has hitherto been concealed by the ball of
the thumb, while the side previously in sight is in turn hidden by the
middle finger. A reverse movement, of course, replaces the dice in
their original position. The action of bringing the hands together, for
the supposed purpose of rubbing the dice with the opposite forefinger,
completely covers the smaller movement of the thumb and finger.
[Illustration: FIG. 117.]
After having exhibited the trick in this form once or twice, you
may vary your mode of operation. For this purpose take the dice
(still retaining their relative position) horizontally between the
thumb and second finger, in the manner depicted in Fig. 117, showing
“three-one” on their upper face; the corresponding “three-one,” or
rather “one-three,” being now covered by the forefinger. As the points
on the opposite faces of a die invariably together amount to seven, it
is obvious that the points on the under side will now be “four-six,”
while the points next to the ball of the thumb will be “six-four.” You
show, alternately raising and lowering the hand, that the points above
are “three-one,” and those below “six-four.” Again going through the
motion of rubbing the dice with the opposite forefinger, you slightly
raise the thumb and depress the middle finger, which will bring the
“six-four” uppermost, and the “three-one” or “one-three” undermost.
This maybe repeated any number of times; or you may, by moving the
thumb and finger accordingly, produce either “three-one” or “six-four”
apparently both above and below the dice.
The trick may, of course, be varied as regards the particular points,
but the dice must, in any case, be so placed as to have similar points
on two adjoining faces.
TO NAME, WITHOUT SEEING THEM, THE POINTS OF A PAIR OF DICE.--This is
a mere arithmetical recreation, but it is so good that we cannot
forbear to notice it. You ask the person who threw the dice to choose
which of them he likes, multiply its points by two, add five to the
product, multiply the sum so obtained by five, and add the points of
the remaining die. On his telling you the result, you mentally subtract
twenty-five from it, when the remainder will be a number of two
figures, each representing the points of one of the dice.
Thus, suppose the throws to be five, two. Five multiplied by two are
ten; add five, fifteen, which, multiplied by five, is seventy-five,
to which two (the points of the remaining die) being added, the total
is seventy-seven. If from this you mentally deduct twenty-five, the
remainder is fifty-two, giving the points of the two dice--five and
two. But, you will say, suppose the person who threw had reversed
the arithmetical process, and had taken the points of the second die
(two) as his multiplicand, the result must have been different. Let us
try the experiment. Twice two are four, five added make nine, which,
multiplied by five, is forty-five, and five (the points of the other
die) being added to it, bring the total up to fifty. From this subtract
twenty-five as before. The remainder, twenty-five, again gives the
points of the two dice, but in the reverse order; and the same result
will follow, whatever the throws may be.
[Illustration]