Safecracker Meets Safecracker

Safecracker Meets Safecracker
I learned to pick locks from a guy named Leo Lavatelli. It
turns out that picking ordinary tumbler locks—like Yale locks—is
easy. You try to turn the lock by putting a screwdriver in the
hole (you have to push from the side in order to leave the
hole open). It doesn’t turn because there are some pins inside
which have to be lifted to just the right height (by the key).
Because it is not made perfectly, the lock is held more by one
pin than the others. Now, if you push a little wire
gadget—maybe a paper clip with a slight bump at the end—and
jiggle it back and forth inside the lock, you’ll eventually push
that one pin that’s doing the most holding, up to the right
height. The lock gives, just a little bit, so the first pin stays
up—it’s caught on the edge. Now most of the load is held by
another pin, and you repeat the same random process for a
few more minutes, until all the pins are pushed up.
What often happens is that the screwdriver will slip and you
hear tic-tic-tic, and it makes you mad. There are little springs
that push the pins back down when a key is removed, and
you can hear them click when you let go of the screwdriver.
(Sometimes you intentionally let go of the screwdriver to see if
you’re getting anywhere—you might be pushing the wrong way,
for instance.) The process is something like Sisyphus: you’re
always falling back downhill.
It’s a simple process, but practice helps a lot. You learn how
hard to push on things—hard enough so the pins will stay up,
but not so hard that they won’t go up in the first place. What
is not really appreciated by most people is that they’re
perpetually locking themselves in with locks everywhere, and it’s
not very hard to pick them.
When we started to work on the atomic bomb project at
Los Alamos, everything was in such a hurry that it wasn’t
really ready. All the secrets of the project—everything about the
atomic bomb—were kept in filing cabinets which, if they had
locks at all, were locked with padlocks which had maybe only
three pins: they were as easy as pie to open.
To improve security the shop ouffitted every filing cabinet
with a long rod that went down through the handles of the
drawers and that was fastened by a padlock.
Some guy said to me, “Look at this new thing the shop put
on—can you open the cabinet now?”
I looked at the back of the cabinet and saw that the
drawers didn’t have a solid bottom. There was a slot with a
wire rod in each one that held a slidable piece (which holds
the papers up inside the drawer). I poked in from the back,
slid the piece back, and began pulling the papers out through
the slot. “Look!” I said. “I don’t even have to pick the lock.”
Los Alamos was a very cooperative place, and we felt it our
responsibility to point out things that should be improved. I’d
keep complaining that the stuff was unsafe, and although
everybody thought it was safe because there were steel rods
and padlocks, it didn’t mean a damn thing.
To demonstrate that the locks meant nothing, whenever I
wanted somebody’s report and they weren’t around, I’d just go
in their office, open the filing cabinet, and take it out. When I
was finished I would give it back to the guy: “Thanks for your
report.”
“Where’d you get it?”
“Out of your filing cabinet.”
“But I locked it!”
“I know you locked it. The locks are no good.”
Finally some filing cabinets came which had combination
locks on them made by the Mosler Safe Company. They had
three drawers. Pulling the top drawer out would release the
other drawers by a catch. The top drawer was opened by
turning a combination wheel to the left, right, and left for the
combination, and then right to number ten, which would draw
back a bolt inside. The whole filing cabinet could be locked by
closing the bottom drawers first, then the top drawer, and
spinning the combination wheel away from number ten, which
pushed up the bolt.
These new filing cabinets were an immediate challenge,
naturally. I love puzzles. One guy tries to make something to
keep another guy out; there must be a way to beat it!
I had first to understand how the lock worked, so I took
apart the one in my office. The way it worked is this: There
are three discs on a single shaft, one behind the other; each
has a notch in a different place. The idea is to line up the
notches so that when you turn the wheel to ten, the little
friction drive will draw the bolt down into the slot generated by
the notches of the three discs.
Now, to turn the discs, there’s a pin sticking out from the
back of the combination wheel, and a pin sticking up from the
first disc at the same radius. Within one turn of the
combination wheel, you’ve picked up the first disc.
On the back of the first disc there’s a pin at the same
radius as a pin on the front of the second disc, so by the
time you’ve spun the combination wheel around twice, you’ve
picked up the second disc as well.
Keep turning the wheel, and a pin on the back of the
second disc will catch a pin on the front of the third disc,
which you now set into the proper position with the first
number of the combination.
Now you have to turn the combination wheel the other way
one full turn to catch the second disc from the other side, and
then continue to the second number of the combination to set
the second disc.
Again you reverse direction and set the first disc to its
proper place. Now the notches are lined up, and by turning
the wheel to ten, you open the cabinet.
Well, I struggled, and I couldn’t get anywhere. I bought a
couple of safecracker books, but they were all the same. In the
beginning of the book there are some stories of the fantastic
achievements of the safecracker, such as the woman caught in
a meat refrigerator who is freezing to death, but the
safecracker, hanging upside down, opens it in two minutes. Or
there are some precious furs or gold bullion under water,
down in the sea, and the safecracker dives down and opens
the chest.
In the second part of the book, they tell you how to crack
a safe. There are all kinds of ninny-pinny, dopey things, like “It
might be a good idea to try a date for the combination,
because lots of people like to use dates.” Or “Think of the
psychology of the owner of the safe, and what he might use
for the combination.” And “The secretary is often worried that
she might forget the combination of the safe, so she might
write it down in one of the following places—along the edge of
her desk drawer, on a list of names and addresses … and so
on.
They did tell me something sensible about how to open
ordinary safes, and it’s easy to understand. Ordinary safes have
an extra handle, so if you push down on the handle while
you’re turning the combination wheel, things being unequal (as
with locks), the force of the handle trying to push the bolt
down into the notches (which are not lined up) is held up
more by one disc than another. When the notch on that disc
comes under the bolt, there’s a tiny click that you can hear
with a stethoscope, or a slight decrease in friction that you can
feel (you don’t have to sandpaper your fingertips), and you
know, “There’s a number!”
You don’t know whether it’s the first, second, or third
number, but you can get a pretty good idea of that by finding
out how many times you have to turn the wheel the other
way to hear the same click again. If it’s a little less than once,
it’s the first disc; if it’s a little less than twice, it’s the second
disc (you have to make a correction for the thickness of the
pins).
This useful trick only works on ordinary safes, which have
the extra handle, so I was stymied.
I tried all kinds of subsidiary tricks with the cabinets, such as
finding out how to release the latches on the lower drawers,
without opening the top drawer, by taking off a screw in front
and poking around with a piece of hanger wire.
I tried spinning the combination wheel very rapidly and then
going to ten, thus putting a little friction on, which I hoped
would stop a disc at the right point in some manner. I tried all
kinds of things. I was desperate.
I also did a certain amount of systematic study. For instance,
a typical combination was 69-32-21. How far off could a
number be when you’re opening the safe? If the number was
69, would 68 work? Would 67 work? On the particular locks
we had, the answer was yes for both, but 66 wouldn’t work.
You could he off by two in either direction. That meant you
only had to try one out of five numbers, so you could try
zero, five, ten, fifteen, and so on. With twenty such numbers
on a wheel of 100, that was 8000 possibilities instead of the
1,000,000 you would get if you had to try every single
number.
Now the question was, how long would it take me to try the
8000 combinations? Suppose I’ve got the first two numbers
right of a combination I’m trying to get. Say the numbers are
69-32, but I don’t know it—I’ve got them as 70-30. Now I can
try the twenty possible third numbers without having to set up
the first two numbers each time. Now let’s suppose I have
only the first number of the combination right. After trying the
twenty numbers on the third disc, I move the second wheel
only a little bit, and then do another twenty numbers on the
third wheel.
I practiced all the time on my own safe so I could do this
process as fast as I could and not get lost in my mind as to
which number I was pushing and mess up the first number.
Like a guy who practices sleight of hand, I got it down to an
absolute rhythm so I could try the 400 possible back numbers
in less than half an hour. That meant I could open a safe in a
maximum of eight hours—with an average time of four hours.
There was another guy there at Los Alamos named Staley
who was also interested in locks. We talked about it from time
to time, but we weren’t getting anywhere much. After I got this
idea how to open a safe in an average time of four hours, I
wanted to show Staley how to do it, so I went into a guy’s
office over in the computing department and asked, “Do you
mind if I use your safe? I’d like to show Staley something.”
Meanwhile some guys in the computing department came
around and one of them said, “Hey, everybody; Feynman’s
gonna show Staley how to open a safe, ha, ha, ha!” I wasn’t
going to actually open the safe; I was just going to show
Staley this way of quickly trying the back two numbers without
losing your place and having to set up the first number again.
I began. “Let’s suppose that the first number is forty, and
we’re trying fifteen for the second number. We go back and
forth, ten; back five more and forth, ten; and so on. Now
we’ve tried all the possible third numbers. Now we try twenty
for the second number: we go back and forth, ten; back five
more and forth, ten; back five more and forth, CLICK!” My
jaw dropped: the first and second numbers happened to be
right!
Nobody saw my expression because my back was towards
them. Staley looked very surprised, but both of us caught on
Very quickly as to what happened, so I pulled the top drawer
out with a flourish and said, “And there you are!”
Staley said, “I see what you mean; it’s a very good
scheme”—and we walked out. Everybody was amazed. It was
complete luck. Now I really had a reputation for opening
safes.
It took me about a year and a half to get that far (of
course, I was working on the bomb, too!) but I figured that I
had the safes beaten, in the sense that if there was a real
difficulty—if somebody was lost, or dead, and nobody else knew
the combination but the stuff in the filing cabinet was
needed—I could open it. After reading what preposterous things
the safecrackers claimed, I thought that was a rather
respectable accomplishment.
We had no entertainment there at Los Alamos, and we had
to amuse ourselves somehow, so fiddling with the Mosler lock
on my filing cabinet was one of my entertainments. One day I
made an interesting observation: When the lock is opened and
the drawer has been pulled out and the wheel is left on ten
(which is what people do when they’ve opened their filing
cabinet and are taking papers out of it), the bolt is still down.
Now what does that mean, the bolt is still down? It means the
bolt is in the slot made by the three discs, which are still
properly lined up. Ahhhh!
Now, if I turn the wheel away from ten a little bit, the bolt
comes up; if I immediately go back to ten, the bolt goes back
down again, because I haven’t yet disturbed the slot. If I keep
going away from ten in steps of five, at some point the bolt
won’t go back down when I go back to ten: the slot has just
been disturbed. The number just before, which still let the bolt
go down, is the last number of the combination!
I realized that I could do the same thing to find the second
number: As soon as I know the last number, I can turn the
wheel around the other way and again, in lumps of five, push
the second disc bit by bit until the bolt doesn’t go down. The
number just before would be the second number.
If I were very patient I would be able to pick up all three
numbers that way, but the amount of work involved in picking
up the first number of the combination by this elaborate
scheme would be much more than just trying the twenty
possible first numbers with the other two numbers that you
already know, when the filing cabinet is closed.
I practiced and I practiced until I could get the last two
numbers off an open filing cabinet, hardly looking at the dial.
Then, when I’d be in some guy’s office discussing some physics
problem, I’d lean against his opened filing cabinet, and just like
a guy who’s jiggling keys absent-mindedly while he’s talking, I’d
just wobble the dial back and forth, back and forth. Sometimes
I’d put my finger on the bolt so I wouldn’t have to look to
see if it’s coming up. In this way I picked off the last two
numbers of various filing cabinets. When I got back to my
office I would write the two numbers down on a piece of
paper that I kept inside the lock of my filing cabinet. I took
the lock apart each time to get the paper—I thought that was
a very safe place for them.
After a while my reputation began to sail, because things like
this would happen: Somebody would say, “Hey, Feynman!
Christy’s out of town and we need a document from his
safe—can you open it?”
If it was a safe I knew I didn’t have the last two numbers
of, I would simply say, “I’m sorry, but I can’t do it now; I’ve
got this work that I have to do.” Otherwise, I would say,
“Yeah, but I gotta get my tools.” I didn’t need any tools, but
I’d go back to my office, open my filing cabinet, and look at
my little piece of paper: “Christy—35, 60.” Then I’d get a
screwdriver and go over to Christy’s office and close the door
behind me. Obviously not everybody is supposed to be allowed
to know how to do this!
I’d be in there alone and I’d open the safe in a few
minutes. All I had to do was try the first number at most
twenty times, then sit around, reading a magazine or
something, for fifteen or twenty minutes. There was no use
trying to make it look too easy; somebody would figure out
there was a trick to it! After a while I’d open the door and
say, “It’s open.”
People thought I was opening the safes from scratch. Now I
could maintain the idea, which began with that accident with
Staley, that I could open safes cold. Nobody figured out that I
was picking the last two numbers off their safes, even
though—perhaps because—I was doing it all the time, like a
card sharp walking around all the time with a deck of cards,
I often went to Oak Ridge to check up on the safety of the
uranium plant. Everything was always in a hurry because it
was wartime, and one time I had to go there on a weekend.
It was Sunday, and we were in this fella’s office—a general, a
head or a vice president of some company, a couple of other
big muck-a-mucks, and me. We were gathered together to
discuss a report that was in the fella’s safe—a secret
safe—when suddenly he realized that he didn’t know the
combination. His secretary was the only one who knew it, so
he called her home and it turned out she had gone on a
picnic up in the hills.
While all this was going on, I asked, “Do you mind if I
fiddle with the safe?”
“Ha, ha, ha—not at all!” So I went over to the safe and
started to fool around.
They began to discuss how they could get a car to try to
find the secretary, and the guy was getting more and more
embarrassed because he had all these people waiting and he
was such a jackass he didn’t know how to open his own safe.
Everybody was all tense and getting mad at him, when
CLICK!—the safe opened.
In 10 minutes I had opened the safe that contained all the
secret documents about the plant. They were astonished. The
safes were apparently not very safe. It was a terrible shock: All
this “eyes only” stuff, top secret, locked in this wonderful secret
safe, and this guy opens it in ten minutes!
Of course I was able to open the safe because of my
perpetual habit of taking the last two numbers off. While in
Oak Ridge the month before, I was in the same office when
the safe was open and I took the numbers off in an
absentminded way—I was always practicing my obsession.
Although I hadn’t written them down, I was able to vaguely
remember what they were. First I tried 40-15, then 15-40, but
neither of those worked. Then I tried 10-45 with all the first
numbers, and it opened.
A similar thing happened on another weekend when I was
visiting Oak Ridge. I had written a report that had to be OKed
by a colonel, and it was in his safe. Everybody else keeps
documents in filing cabinets like the ones at Los Alamos, but
he was a colonel, so he had a much fancier, two-door safe
with big handles that pull four ¾-inch-thick steel bolts from the
frame. The great brass doors swung open and he took out my
report to read.
Not having had an opportunity to see any really good safes,
I said to him, “Would you mind, while you’re reading my
report, if I looked at your safe?”
“Go right ahead,” he said, convinced that there was nothing
I could do. I looked at the back of one of the solid brass
doors, and I discovered that the combination wheel was
connected to a little lock that looked exactly the same as the
little unit that was on my filing cabinet at Los Alamos. Same
company, same little bolt, except that when the bolt came
down, the big handles on the safe could then move some rods
sideways, and with a hunch of levers you could pull back all
those ¾-inch steel rods. The whole lever system, it appeared,
depends on the same little bolt that locks filing cabinets.
Just for the sake of professional perfection, to make sure it
was the same, I took the two numbers off the same way I did
with the filing cabinet safes.
Meanwhile, he was reading the report. When he’d finished
he said, “All right, it’s fine.” He put the report in the safe,
grabbed the big handles, and swung the great brass doors
together. It sounds so good when they close, but I know it’s
all psychological, because it’s nothing but the same damn lock.
I couldn’t help but needle him a little bit (I always had a
thing about military guys, in such wonderful uniforms) so I
said, “The way you close that safe, I get the idea that you
think things are safe in there.”
“Of course.”
“The only reason you think they’re safe in there is because
civilians call it a ‘safe.’” (I put the word “civilians” in there to
make it sound as if he’d been had by civilians.)
He got very angry. “What do you mean—it’s not safe?”
“A good safecracker could open it in thirty minutes.”
“Can you open it in thirty minutes?”
“I said a good safecracker. It would take me about
forty-five.”
“Well!” he said. “My wife is waiting at home for me with
supper, but I’m gonna stay here and watch you, and you’re
gonna sit down there and work on that damn thing for
forty-five minutes and not open it!” He sat down in his big
leather chair, put his feet up on his desk, and read.
With complete confidence I picked up a chair, carried it over
to the safe and sat down in front of it. I began to turn the
wheel at random, just to make some action.
After about five minutes, which is quite a long time when
you’re just sitting and waiting, he lost some patience: “Well, are
you making any progress?”
“With a thing like this, you either open it or you don’t.”
I figured one or two more minutes would be about time, so
I began to work in earnest and two minutes later, CLINK—it
opened.
The colonel’s jaw dropped and his eyes bugged out.
“Colonel,” I said, in a serious tone, “let me tell you
something about these locks: When the door to the safe or the
top drawer of the filing cabinet is left open, it’s very easy for
someone to get the combination. That’s what I did while you
were reading my report, just to demonstrate the danger. You
should insist that everybody keep their filing cabinet drawers
locked while they’re working, because when they’re open,
they’re very, very vulnerable.”
“Yeah! I see what you mean! That’s very interesting!” We
were on the same side after that.
The next time I went to Oak Ridge, all the secretaries and
people who knew who I was were telling me, “Don’t come
through here! Don’t come through here!”
The colonel had sent a note around to everyone in the plant
which said, “During his last visit, was Mr. Feynman at any time
in your office, near your office, or walking through your
office?” Some people answered yes; others said no. The ones
who said yes got another note: “Please change the combination
of your safe.”
That was his solution: I was the danger. So they all had to
change their combinations on account of me. It’s a pain in the
neck to change a combination and remember the new one, so
they were all mad at me and didn’t want me to come near
them: they might have to change their combination once again.
Of course, their filing cabinets were still left open while they
were working!
A library at Los Alamos held all of the documents we had
ever worked on: It was a solid, concrete room with a big,
beautiful door which had a metal wheel that turns—like a
safe-deposit vault. During the war I had tried to look at it
closely. I knew the girl who was the librarian, and I begged
her to let me play with it a little bit. I was fascinated by it: it
was the biggest lock I ever saw! I discovered that I could
never use my method of picking off the last two numbers to
get in. In fact, while turning the knob while the door was
open, I made the lock close, so it was sticking out, and they
couldn’t close the door again until the girl came and opened
the lock again. That was the end of my fiddling around with
that lock. I didn’t have time to figure out how it worked; it
was much beyond my capacity.
During the summer after the war I had some documents to
write and work to finish up, so I went back to Los Alamos
from Cornell, where I had taught during the year. In the
middle of my work I had to refer to a document that I had
written before but couldn’t remember, and it was down in the
library.
I went down to get the document, and there was a soldier
walking back and forth, with a gun. It was a Saturday, and
after the war the library was closed on Saturdays.
Then I remembered what a good friend of mine, Frederic de
Hoffman, had done. He was in the Declassification Section.
After the war the army was thinking of declassifying some
documents, and he had to go back and forth to the library so
much—look at this document, look at that document, check
this, check that—that he was going nuts! So he had a copy of
every document—all the secrets to the atomic bomb—in nine
filing cabinets in his office.
I went down to his office, and the lights were on. It looked
as if whoever was there—perhaps his secretary—had just
stepped out for a few minutes, so I waited. While I was waiting
I started to fiddle around with the combination wheel on one
of the filing cabinets. (By the way, I didn’t have the last two
numbers for de Hoffman’s safes; they were put in after the
war, after I had left.)
I started to play with one of the combination wheels and
began to think about the safecracker books. I thought to
myself, “I’ve never been much impressed by the tricks
described in those books, so I’ve never tried them, but let’s see
if we can open de Hoffman’s safe by following the book.”
First trick, the secretary: she’s afraid she’s going to forget
the combination, so she writes it down somewhere. I started to
look in some of the places mentioned in the book. The desk
drawer was locked, but it was an ordinary lock like Leo
Lavatelli taught me how to open—ping! I look along the edge:
nothing.
Then I looked through the secretary’s papers. I found a
sheet of paper that all the secretaries had, with the Greek
letters carefully made—so they could recognize them in
mathematical formulas—and named. And there, carelessly written
along the top of the paper, was pi = 3.14159. Now, that’s six
digits, and why does a secretary have to know the numerical
value of pi? It was obvious; there was no other reason!
I went over to the filing cabinets and tried the first one:
31-41-59. It didn’t open. Then I tried 59-41-31. That didn’t
work either. Then 95-14-13. Backwards, forwards, upside down,
turn it this way, turn it that—nothing!
I closed the desk drawer and started to walk out the door,
when I thought of the safecracker books again: Next, try the
psychology method. I said to myself, “Freddy de Hoffman is
just the kind of guy to use a mathematical constant for a safe
combination.”
I went back to the first filing cabinet and tried
27-18-28—CLICK! It opened! (The mathematical constant second
in importance to pi is the base of natural logarithms, e:
2.71828 …) There were nine filing cabinets, and I had opened
the first one, but the document I wanted was in another
one—they were in alphabetical order by author. I tried the
second filing cabinet: 27-18-28–CLICK! It opened with the same
combination. I thought, “This is wonderful! I’ve opened the
secrets to the atomic bomb, but if I’m ever going to tell this
story, I’ve got to make sure that all the combinations are really
the same!” Some of the filing cabinets were in the next room,
so I tried 27-18-28 on one of them, and it opened. Now I’d
opened three safes—all the same.
I thought to myself, “Now I could write a safecracker book
that would beat every one, because at the beginning I would
tell how I opened safes whose contents were bigger and more
valuable than what any safecracker anywhere had
opened—except for a life, of course—but compared to the furs
or the gold bullion, I have them all beat: I opened the safes
which contained all the secrets to the atomic bomb: the
schedules for the production of the plutonium, the purification
procedures, how much material is needed, how the bomb
works, how the neutrons are generated, what the design is, the
dimensions—the entire information that was known at Los
Alamos: the whole shmeer! ”
I went back to the second filing cabinet and took out the
document I wanted. Then I took a red grease pencil and a
piece of yellow paper that was lying around in the office and
wrote, “I borrowed document no. LA4312—Feynman the
safecracker.” I put the note on top of the papers in the filing
cabinet and closed it.
Then I went to the first one I had opened and wrote
another note: “This one was no harder to open than the other
one—Wise Guy” and shut the cabinet.
Then in the other cabinet, in the other room, I wrote,
“When the combinations are all the same, one is no harder to
open than another—Same Guy” and I shut that one. I went
back to my office and wrote my report.
That evening I went to the cafeteria and ate supper. There
was Freddy de Hoffman. He said he was going over to his
office to work, so just for fun I went with him.
He started to work, and soon he went into the other room
to open one of the filing cabinets in there—something I hadn’t
counted on—and he happened to open the filing cabinet I had
put the third note in, first. He opened the drawer, and he saw
this foreign object in there—this bright yellow paper with
something scrawled on it in bright red crayon.
I had read in books that when somebody is afraid, his face
gets sallow, but I had never seen it before. Well, it’s absolutely
true. His face turned a gray, yellow green—it was really
frightening to see. He picked up the paper, and his hand was
shaking. “L-l-look at this!” he said, trembling.
The note said, “When the combinations are all the same,
one is no harder to open than another—Same Guy.”
“What does it mean?” I said.
“All the c-c-combinations of my safes are the s-s-same!” he
stammered.
“That ain’t such a good idea.”
“I-I know that n-now!” he said, completely shaken.
Another effect of the blood draining from the face must be
that the brain doesn’t work right. “He signed who it was! He
signed who it was!” he said.
“
What?” (I hadn’t put my name on that one.)
“Yes,” he said, “it’s the same guy who’s been trying to get
into Building Omega!”
All during the war, and even after, there were these
perpetual rumors: “Somebody’s been trying to get into Building
Omega!” You see, during the war they were doing experiments
for the bomb in which they wanted to get enough material
together for the chain reaction to just get started. They would
drop one piece of material through another, and when it went
through, the reaction would start and they’d measure how
many neutrons they got. The piece would fall through so fast
that nothing should build up and explode. Enough of a reaction
would begin, however, so they could tell that things were really
starting correctly, that the rates were right, and everything was
going according to prediction—a very dangerous experiment!
Naturally, they were not doing this experiment in the middle
of Los Alamos, but off several miles, in a canyon several mesas
over, all isolated. This Building Omega had its own fence
around it with guard towers. In the middle of the night when
everything’s quiet, some rabbit comes out of the brush and
smashes against the fence and makes a noise. The guard
shoots. The lieutenant in charge comes around. What’s the
guard going to say—that it was only a rabbit? No. “Somebody’s
been trying to get into Building Omega and I scared him off!”
So de Hoffman was pale and shaking, and he didn’t realize
there was a flaw in his logic: it was not clear that the same
guy who’d been trying to get into Building Omega was the
same guy who was standing next to him.
He asked me what to do.
“Well, see if any documents are missing.”
“It looks all right,” he said. “I don’t see any missing.”
I tried to steer him to the filing cabinet I took my document
out of. “Well, uh, if all the combinations are the same, perhaps
he’s taken something from another drawer.”
“Right!” he said, and he went back into his office and
opened the first filing cabinet and found the second note I
wrote: “This one was no harder than the other one—Wise
Guy.”
By that time it didn’t make any difference whether it was
“Same Guy” or “Wise Guy”: It was completely clear to him
that it was the guy who was trying to get into Building Omega.
So to convince him to open the filing cabinet with my first
note in it was particularly difficult, and I don’t remember how I
talked him into it.
He started to open it, so I began to walk down the hall,
because I was a little bit afraid that when he found out who
did it to him, I was going to get my throat cut!
Sure enough, he came running down the hall after me, but
instead of being angry, he practically put his arms around me
because he was so completely relieved that this terrible burden
of the atomic secrets being stolen was only me doing mischief.
A few days later de Hoffman told me that he needed
something from Kerst’s safe. Donald Kerst had gone back to
Illinois and was hard to reach. “If you can open all my safes
using the psychological method,” de Hoffman said (I had told
him how I did it), “maybe you could open Kerst’s safe that
way.”
By now the story had gotten around, so several people
came to watch this fantastic process where I was going to
open Kerst’s safe—cold. There was no need for me to be
alone. I didn’t have the last two numbers to Kerst’s safe, and
to use the psychology method I needed people around who
knew Kerst.
We all went over to Kerst’s office and I checked the
drawers for clues; there was nothing. Then I asked them,
“What kind of a combination would Kerst use—a mathematical
constant?”
“Oh, no!” de Hoffman said. “Kerst would do something very
simple.”
I tried 10-20-30, 20-40-60, 60-40-20, 30-20-10. Nothing.
Then I said, “Do you think he would use a date?”
“Yeah!” they said. “He’s just the kind of guy to use a date.”
We tried various dates: 8-6-45, when the bomb went off;
86-19-45; this date; that date; when the project started.
Nothing worked.
By this time most of the people had drifted off. They didn’t
have the patience to watch me do this, but the only way to
solve such a thing is patience!
Then I decided to try everything from around 1900 until
now. That sounds like a lot, but it’s not: the first number is a
month, one through twelve, and I can try that using only three
numbers: ten, five, and zero. The second number is a day,
from one to thirty-one, which I can try with six numbers. The
third number is the year, which was only forty-seven numbers
at that time, which I could try with nine numbers. So the
8000 combinations had been reduced to 162, something I
could try in fifteen or twenty minutes.
Unfortunately I started with the high end of the numbers for
the months, because when I finally opened it, the combination
was 0-5-35.
I turned to de Hoffman. “What happened to Kerst around
January 5, 1935?”
“His daughter was born in 1936,” de Hoffman said. “It must
be her birthday.”
Now I had opened two safes cold. I was getting good. Now
I was professional.
That same summer after the war, the guy from the property
section was trying to take back some of the things the
government had bought, to sell again as surplus. One of the
things was a Captain’s safe. We all knew about this safe. The
Captain, when he arrived during the war, decided that the filing
cabinets weren’t safe enough for the secrets he was going to
get, so he had to have a special safe.
The Captain’s office was on the second floor of one of the
flimsy wooden buildings that we all had our offices in, and the
safe he ordered was a heavy steel safe. The workmen had to
put down platforms of wood and use special jacks to get it up
the steps. Since there wasn’t much amusement, we all watched
this big safe being moved up to his office with great effort, and
we all made jokes about what kind of secrets he was going to
keep in there. Some fella said we oughta put our stuff in his
safe, and let him put his stuff in ours. So everyone knew
about this safe.
The property section man wanted it for surplus, but first it
had to be emptied, and the only people who knew the
combination were the Captain, who was in Bikini, and Alvarez,
who’d forgotten it. The man asked me to open it.
I went up to his old office and said to the secretary, “Why
don’t you phone the Captain and ask him the combination?”
“I don’t want to bother him,” she said.
“Well, you’re gonna bother me for maybe eight hours. I
won’t do it unless you make an attempt to call him.”
“OK, OK!” she said. She picked up the telephone and I went
into the other room to look at the safe. There it was, that
huge, steel safe, and its doors were wide open.
I went back to the secretary. “It’s open.”
“Marvelous!” she said, as she put down the phone.
“No,” I said, “it was already open.”
“Oh! I guess the property section was able to open it after
all.”
I went down to the man in the property section. “I went up
to the safe and it was already open.”
“Oh, yeah,” he said; “I’m sorry I didn’t tell you. I sent our
regular locksmith up there to drill it, but before he drilled it he
tried to open it, and he opened it.”
So! First information: Los Alamos now has a regular
locksmith. Second information: This man knows how to drill
safes, something I know nothing about. Third information: He
can open a safe cold—in a few minutes. This is a real
professional, a real source of information. This guy I have to
meet.
I found out he was a locksmith they had hired after the
war (when they weren’t as concerned about security) to take
care of such things. It turned out that he didn’t have enough
work to do opening safes, so he also repaired the Marchant
calculators we had used. During the war I repaired those
things all the time—so I had a way to meet him.
Now I have never been surreptitious or tricky about meeting
somebody; I just go right up and introduce myself. But in this
case it was so important to meet this man, and I knew that
before he would tell me any of his secrets on how to open
safes, I would have to prove myself.
I found out where his room was—in the basement of the
theoretical physics section, where I worked—and I knew he
worked in the evening, when the machines weren’t being used.
So, at first I would walk past his door on my way to my
office in the evening. That’s all; I’d just walk past.
A few nights later, just a “Hi.” After a while, when he saw it
was the same guy walking past, he’d say “Hi,” or “Good
evening.”
A few weeks of this slow process and I see he’s working on
the Marchant calculators. I say nothing about them; it isn’t time
yet.
We gradually say a little more: “Hi! I see you’re working
pretty hard!”
“Yeah, pretty hard”—that kind of stuff.
Finally, a breakthrough: he invites me for soup. It’s going
very good now. Every evening we have soup together. Now I
begin to talk a little bit about the adding machines, and he tells
me he has a problem. He’s been trying to put a succession of
spring-loaded wheels back onto a shaft, and he doesn’t have
the right tool, or something; he’s been working on it for a
week. I tell him that I used to work on those machines during
the war, and “I’ll tell you what: you just leave the machine out
tonight, and I’ll have a look at it tomorrow.”
“OK,” he says, because he’s desperate.
The next day I looked at the damn thing and tried to load
it by holding all the wheels in my hand. It kept snapping back.
I thought to myself, “If he’s been trying the same thing for a
week, and I’m trying it and can’t do it, it ain’t the way to do
it!” I stopped and looked at it very carefully, and I noticed that
each wheel had a little hole—just a little hole. Then it dawned
on me: I sprung the first one; then I put a piece of wire
through the little hole. Then I sprung the second one and put
the wire through it. Then the next one, the next one—like
putting beads on a string—and I strung the whole thing the
first time I tried it, got it all in line, pulled the wire out, and
everything was OK.
That night I showed him the little hole and how I did it,
and from then on we talked a lot about machines; we got to
be good friends. Now, in his office there were a lot of little
cubbyholes that contained locks half taken apart, and pieces
from safes, too. Oh, they were beautiful! But I still didn’t say a
word about locks and safes.
Finally, I figured the day was coming, so I decided to put
out a little bit of bait about safes: I’d tell him the only thing
worth a damn that I knew about them—that you can take the
last two numbers off while it’s open. “Hey!” I said, looking over
at the cubbyholes. “I see you’re working on Mosler safes.”
“Yeah.”
“You know, these locks are weak. If they’re open, you can
take the last two numbers off …”
“You can?” he said, finally showing some interest.
“Yeah.”
“Show me how,” he said. I showed him how to do it, and
he turned to me. “What’s your name?” All this time we had
never exchanged names.
“Dick Feynman,” I said.
“God! You’re Feynman!” he said in awe. “The great
safecracker! I’ve heard about you; I’ve wanted to meet you for
so long! I want to learn how to crack a safe from you.”
“What do you mean? You know how to open safes cold.”
“I don’t.”
“Listen, I heard about the Captain’s safe, and I’ve been
working pretty hard all this time because I wanted to meet
you. And you tell me you don’t know how to open a safe
cold.”
“That’s right.”
“Well you must know how to drill a safe.”
“I don’t know how to do that either.”
“WHAT?” I exclaimed. “The guy in the property section said
you picked up your tools and went up to drill the Captain’s
safe.”
“Suppose you had a job as a locksmith,” he said, “and a
guy comes down and asks you to drill a safe. What would you
do?”
“Well,” I replied, “I’d make a fancy thing of putting my tools
together, pick them up and take them to the safe. Then I’d
put my drill up against the safe somewhere at random and I’d
go vvvvvvvvvvv, so I’d save my job.”
“That’s exactly what I was going to do.”
“But you opened it! You must know how to crack safes.”
“Oh, yeah. I knew that the locks come from the factory set
at 25-0-25 or 50-25-50, so I thought, ‘Who knows; maybe the
guy didn’t bother to change the combination,’ and the second
one worked.”
So I did learn something from him—that he cracked safes
by the same miraculous methods that I did. But even funnier
was that this big shot Captain had to have a super, super safe,
and had people go to all that trouble to hoist the thing up into
his office, and he didn’t even bother to set the combination.
I went from office to office in my building, trying those two
factory combinations, and I opened about one safe in five