card 1. Add the uncut cards on top and bottom, then
align the holes, and bolt them all together. Use a
bolt that fits the holes snugly. A larger-diameter hole
and bolt work best, though I’ve gotten away with ¼"
bolts when using thin cards. The rotation may be
repeated, restoring the cards to their original order.
There are other ways to make the cuts, but after
extensive research in the TT T laboratories, we have
concluded that this is the most foolproof.
A six-card version requires two pairs of cards to be
cut as described above. Slide the right tab of card 2
under the left tab of card 1. Then slide the right tab
of card 3 under the left tabs of both 1 and 2. Finally
slide the right tab of card 4 under the left tabs of 1,
2, and 3. Add the uncut cards on top and bottom,
align the holes, and bolt them all together.
How about going for broke? Prepare three sets of
two cut cards, interleave them, and sandwich them
between two uncut cards, for a total of 8 cards. Can
it possibly work? Yes, quite well, but with so many
cards it’s best to use thinner cards, such as 3"× 5"
file cards. You can number them, or use different
colors, and develop your own presentation routine.
Note, as you play with this, that the “cut” cards
undergo a cyclic permutation when you rotate them
180°. The top and bottom cards stay put and serve
to hide the surgery you did on the others. You can
“cut” the fanned cards at any point before rotating,
but cutting next to the end cards does nothing
interesting. Of course the action may be repeated,
cutting at different points. When you wish to restore
the cards to the original order, cut between the
cards that were originally next to the end cards.
Yes, the idea can be modified to an odd number of
cards. A five-card version with three inner cut cards
is a good start, which we leave as an exercise for the
reader. Hint: Look at the dotted line in the diagram.
The photos at left show a version I made to tease
my physics students. Students should know the
order of colors in the spectrum, first studied by
Newton. They are: red, orange, yellow, green, blue,
and violet. But some can’t remember them. I show
them this arrangement that I call “Newton’s crutch.”
I tell them that by bolting the colors together, we
ensure they can’t get out of order. Then I do “the
move” and the colors are disordered.
Donald Simanek is emeritus professor of physics at Lock
Haven University of Pennsylvania. He writes about science,
pseudoscience, and humor at www.lhup.edu/~dsimanek.
BOOK REVIEW
Automagic
Science Magic Tricks
by Nathan Shalit
$4, Dover Publications
This 120-page book of simple magic tricks
will show you how to make a paper clip that
defies gravity, a balloon that doesn’t burst
when you poke it with a needle, a cup of tea
that turns into water at your command, a
handkerchief that burns without scorching,
and other objects that appear to do the
impossible.
All the tricks in the book can be prepared
and performed by a 10-year-old, but many
of them will fool even keen-eyed adults.
I remember trying out the Magic Glass Rod
on my parents’ friends, and they were mystified as to how a solid glass tube was able to
flip some words upside-down, but not others.
(To strengthen the effect, I used a red pen to
write the words that flip and a blue pen for
the words that don’t and told them that the
inks reacted differently.)
The nice thing about Shalit’s inexpensive
book is that all the tricks rely on science, not
sleight of hand, to do their magic. Your job,
as the magician, is to present the tricks and
pretend the special powers are emanating
from you, and not the chemicals, magnets,
static electricity, or other natural phenomena
that make them work.
—Mark Frauenfelder
Make: 177
