coming down ahead of time. So they just went crazy and
rented ranch houses all around the neighborhood. We stayed at first in a
ranch house and would drive in in the morning. The first morning I drove in
was tremendously impressive. The beauty of the scenery, for a person from
the East who didn't travel much, was sensational. There are the great cliffs
that you've probably seen in pictures. You'd come up from below and be very
surprised to see this high mesa. The most impressive thing to me was that,
as I was going up, I said that maybe there had been Indians living here, and
the guy who was driving stopped the car and walked around the corner and
pointed out some Indian caves that you could inspect. It was very exciting.
When I got to the site the first time, I saw there was a technical area
that was supposed to have a fence around it ultimately, but it was still
open. Then there was supposed to be a town, and then a big fence further
out, around the town. But they were still building, and my friend Paul Olum,
who was my assistant, was standing at the gate with a clipboard, checking
the trucks coming in and out and telling them which way to go to deliver the
materials in different places.
When I went into the laboratory, I would meet men I had heard of by
seeing their papers in the Physical Review and so on. I had never met them
before. "This is John Williams," they'd say. Then a guy stands up from a
desk that is covered with blueprints, his sleeves all rolled up, and he's
calling out the windows, ordering trucks and things going in different
directions with building material. In other words, the experimental
physicists had nothing to do until their buildings and apparatus were ready,
so they just built the buildings -- or assisted in building the buildings.
The theoretical physicists, on the other hand, could start working
right away, so it was decided that they wouldn't live in the ranch houses,
but would live up at the site. We started working immediately. There were no
blackboards except for one on wheels, and we'd roll it around and Robert
Serber would explain to us all the things that they'd thought of in Berkeley
about the atomic bomb, and nuclear physics, and all these things. I didn't
know very much about it; I had been doing other kinds of things. So I had to
do an awful lot of work.
Every day I would study and read, study and read. It was a very hectic
time. But I had some luck. All the big shots except for Hans Bethe happened
to be away at the time, and what Bethe needed was someone to talk to, to
push his ideas against. Well, he comes in to this little squirt in an office
and starts to argue, explaining his idea. I say, "No, no, you're crazy.
It'll go like this." And he says, "Just a moment," and explains how he's not
crazy, I'm crazy. And we keep on going like this. You see, when I hear about
physics, I just think about physics, and I don't know who I'm talking to, so
I say dopey things like "no, no, you're wrong," or "you're crazy." But it
turned out that's exactly what he needed. I got a notch up on account of
that, and I ended up as a group leader under Bethe with four guys under me.
Well, when I was first there, as I said, the dormitories weren't ready.
But the theoretical physicists had to stay up there anyway. The first place
they put us was in an old school building -- a boys' school that had been
there previously. I lived in a thing called the Mechanics' Lodge. We were
all jammed in there in bunk beds, and it wasn't organized very well because
Bob Christy and his wife had to go to the bathroom through our bedroom. So
that was very uncomfortable.
At last the dormitory was built. I went down to the place where rooms
were assigned, and they said, you can pick your room now. You know what I
did? I looked to see where the girls' dormitory was, and then I picked a
room that looked right across -- though later I discovered a big tree was
growing right in front of the window of that room.
They told me there would be two people in a room, but that would only
be temporary. Every two rooms would share a bathroom, and there would be
double-decker bunks in each room. But I didn't want two people in the room.
The night I got there, nobody else was there, and I decided to try to
keep my room to myself. My wife was sick with TB in Albuquerque, but I had
some boxes of stuff of hers. So I took out a little nightgown, opened the
top bed, and threw the nightgown carelessly on it. I took out some slippers,
and I threw some powder on the floor in the bathroom. I just made it look
like somebody else was there. So, what happened? Well, it's supposed to be a
men's dormitory, see? So I came home that night, and my pajamas are folded
nicely, and put under the pillow at the bottom, and my slippers put nicely
at the bottom of the bed. The lady's nightgown is nicely folded under the
pillow, the bed is all fixed up and made, and the slippers are put down
nicely. The powder is cleaned from the bathroom and nobody is sleeping in
the upper bed.
Next night, the same thing. When I wake up, I rumple up the top bed, I
throw the nightgown on it sloppily and scatter the powder in the bathroom
and so on. I went on like this for four nights until everybody was settled
and there was no more danger that they would put a second person in the
room. Each night, everything was set out very neatly, even though it was a
men's dormitory.
I didn't know it then, but this little ruse got me involved in
politics. There were all kinds of factions there, of course -- the
housewives' faction, the mechanics' faction, the technical peoples' faction,
and so on. Well, the bachelors and bachelor girls who lived in the dormitory
felt they had to have a faction too, because a new rule had been
promulgated: No Women in the Men's Dorm. Well, this is absolutely
ridiculous! After all, we are grown people! What kind of nonsense is this?
We had to have political action. So we debated this stuff, and I was elected
to represent the dormitory people in the town council.
After I'd been in it for about a year and a half, I was talking to Hans
Bethe about something. He was on the big governing council all this time,
and I told him about this trick with my wife's nightgown and bedroom
slippers. He started to laugh. "So that's how you got on the town council,"
he said.
It turned out that what happened was this. The woman who cleans the
rooms in the dormitory opens this door, and all of a sudden there is
trouble: somebody is sleeping with one of the guys! She reports to the chief
charwoman, the chief charwoman reports to the lieutenant, the lieutenant
reports to the major. It goes all the way up through the generals to the
governing board.
What are they going to do? They're going to think about it, that's
what! But, in the meantime, what instructions go down through the captains,
down through the majors, through the lieutenants, through the chars' chief,
through the charwoman? "Just put things back the way they are, clean 'em up,
and see what happens." Next day, same report. For four days, they worried up
there about what they were going to do. Finally they promulgated a rule: No
Women in the Men's Dormitory! And that caused such a stink down below that
they had to elect somebody to represent the...
I would like to tell you something about the censorship that we had
there. They decided to do something utterly illegal and censor the mail of
people inside the United States -- which they have no right to do. So it had
to be set up very delicately as a voluntary thing. We would all volunteer
not to seal the envelopes of the letters we sent out, and it would be all
right for them to open letters coming in to us; that was voluntarily
accepted by us. We would leave our letters open; and they would seal them if
they were OK. If they weren't OK in their opinion, they would send the
letter back to us with a note that there was a violation of such and such a
paragraph of our "understanding."
So, very delicately amongst all these liberal-minded scientific guys,
we finally got the censorship set up, with many rules. We were allowed to
comment on the character of the administration if we wanted to, so we could
write our senator and tell him we didn't like the way things were run, and
things like that. They said they would notify us if there were any
difficulties.
So it was all set up, and here comes the first day for censorship:
Telephone! Briiing!
Me: "What?"
"Please come down."
I come down.
"What's this?"
"It's a letter from my father."
"Well, what is it?"
There's lined paper, and there's these lines going out with dots --
four dots under, one dot above, two dots under, one dot above, dot under
dot...
"What's that?"
I said, "It's a code."
They said, "Yeah, it's a code, but what does it say?"
I said, "I don't know what it says."
They said, "Well, what's the key to the code? How do you decipher it?"
I said, "Well, I don't know."
Then they said, "What's this?"
I said, "It's a letter from my wife -- it says TJXYWZ TW1X3."
"What's that?"
I said, "Another code."
"What's the key to it?"
"I don't know."
They said, "You're receiving codes, and you don't know the key?"
I said, "Precisely. I have a game. I challenge them to send me a code
that I can't decipher, see? So they're making up codes at the other end, and
they're sending them in, and they're not going to tell me what the key is."
Now one of the rules of the censorship was that they aren't going to
disturb anything that you would ordinarily send in the mail. So they said,
"Well, you're going to have to tell them please to send the key in with the
code."
I said, "I don't want to see the key!"
They said, "Well, all right, we'll take the key out."
So we had that arrangement. OK? All right. Next day I get a letter from
my wife that says, "It's very difficult writing because I feel that the
--------
splotch made with ink eradicator.
So I went down to the bureau, and I said, "You're not supposed to touch
the incoming mail if you don't like it. You can look at it, but you're not
supposed to take anything out."
They said, "Don't be ridiculous. Do you think that's the way censors
work -- with ink eradicator? They cut things out with scissors."
I said OK. So I wrote a letter back to my wife and said, "Did you use
ink eradicator in your letter?" She writes back, "No, I didn't use ink
eradicator in my letter, it must have been the _____" -- and there's a hole
cut out of the paper.
So I went back to the major who was supposed to be in charge of all
this and complained. You know, this took a little time, but I felt I was
sort of the representative to get the thing straightened out. The major
tried to explain to me that these people who were the censors had been
taught how to do it, but they didn't understand this new way that we had to
be so delicate about.
So, anyway, he said, "What's the matter, don't you think I have good
will?"
I said, "Yes, you have perfectly good will but I don't think you have
power." Because, you see, he had already been on the job three or four days.
He said, "We'll see about that!" He grabs the telephone, and everything
is straightened out. No more is the letter cut.
However, there were a number of other difficulties. For example, one
day I got a letter from my wife and a note from the censor that said, "There
was a code enclosed without the key, and so we removed it."
So when I went to see my wife in Albuquerque that day, she said, "Well,
where's all the stuff?"
I said, "What stuff?"
She said, "Litharge, glycerine, hot dogs, laundry."
I said, "Wait a minute -- that was a list?"
She said, "Yes."
"That was a code," I said. "They thought it was a code-litharge,
glycerine, etc." (She wanted litharge and glycerine to make a cement to fix
an onyx box.)
All this went on in the first few weeks before we got everything
straightened out. Anyway, one day I'm piddling around with the computing
machine, and I notice something very peculiar. If you take 1 divided by 243
you get .004115226337... It's quite cute: It goes a little cockeyed after
559 when you're carrying but it soon straightens itself out and repeats
itself nicely. I thought it was kind of amusing.
Well, I put that in the mail, and it comes back to me. It doesn't go
through, and there's a little note: "Look at Paragraph 17B." I look at
Paragraph 17B. It says, "Letters are to be written only in English, Russian,
Spanish, Portuguese, Latin, German, and so forth. Permission to use any
other language must be obtained in writing." And then it said, "No codes."
So I wrote back to the censor a little note included in my letter which
said that I feel that of course this cannot be a code, because if you
actually do divide 1 by 243, you do, in fact, get all that, and therefore
there's no more information in the number .004115226337... than there is in
the number 243 -- which is hardly any information at all. And so forth. I
therefore asked for permission to use Arabic numerals in my letters. So I
got that through all right.
There was always some kind of difficulty with the letters going back
and forth. For example, my wife kept mentioning the fact that she felt
uncomfortable writing with the feeling that the censor is looking over her
shoulder. Now, as a rule, we aren't supposed to mention censorship. We
aren't, but how can they tell her? So they keep sending me a note: "Your
wife mentioned censorship." Certainly, my wife mentioned censorship. So
finally they sent me a note that said, "Please inform your wife not to
mention censorship in her letters." So I start my letter: "I have been
instructed to inform you not to mention censorship in your letters." Phoom,
phoooom, it comes right back! So I write, "I have been instructed to inform
my wife not to mention censorship. How in the heck am I going to do it?
Furthermore, why do I have to instruct her not to mention censorship? You
keeping something from me?"
It is very interesting that the censor himself has to tell me to tell
my wife not to tell me that she's... But they had an answer. They said, yes,
that they are worried about mail being intercepted on the way from
Albuquerque, and that someone might find out that there was censorship if
they looked in the mail, and would she please act much more normal.
So I went down the next time to Albuquerque, and I talked to her and I
said, "Now, look, let's not mention censorship." But we had had so much
trouble that we at last worked out a code, something illegal. If I would put
a dot at the end of my signature, it meant I had had trouble again, and she
would move on to the next of the moves that she had concocted. She would sit
there all day long, because she was ill, and she would think of things to
do. The last thing she did was to send me an advertisement which she found
perfectly legitimately. It said, "Send your boyfriend a letter on a jigsaw
puzzle. We sell you the blank, you write the letter on it, take it all
apart, put it in a little sack, and mail it." I received that one with a
note saying, "We do not have time to play games. Please instruct your wife
to confine herself to ordinary letters."
Well, we were ready with the one more dot, but they straightened out
just in time and we didn't have to use it. The thing we had ready for the
next one was that the letter would start, "I hope you remembered to open
this letter carefully because I have included the Pepto-Bismol powder for
your stomach as we arranged." It would be a letter full of powder. In the
office we expected they would open it quickly, the powder would go all over
the floor, and they would get all upset because you are not supposed to
upset anything. They'd have to gather up all this Pepto-Bismol... But we
didn't have to use that one.
As a result of all these experiences with the censor, I knew exactly
what could get through and what could not get through. Nobody else knew as
well as I. And so I made a little money out of all of this by making bets.
One day I discovered that the workmen who lived further out and wanted
to come in were too lazy to go around through the gate, and so they had cut
themselves a hole in the fence. So I went out the gate, went over to the
hole and came in, went out again, and so on, until the sergeant at the gate
began to wonder what was happening. How come this guy is always going out
and never coming in? And, of course, his natural reaction was to call the
lieutenant and try to put me in jail for doing this. I explained that there
was a hole.
You see, I was always trying to straighten people out. And so I made a
bet with somebody that I could tell about the hole in the fence in a letter,
and mail it out. And sure enough, I did. And the way I did it was I said,
You should see the way they administer this place (that's what we were
allowed to say). There's a hole in the fence seventy-one feet away from
such-and-such a place, that's this size and that size, that you can walk
through.
Now, what can they do? They can't say to me that there is no such hole.
I mean, what are they going to do? It's their own hard luck that there's
such a hole. They should fix the hole. So I got that one through.
I also got through a letter that told about how one of the boys who
worked in one of my groups, John Kemeny, had been wakened up in the middle
of the night and grilled with lights in front of him by some idiots in the
army there because they found out something about his father, who was
supposed to be a communist or something. Kemeny is a famous man now.
There were other things. Like the hole in the fence, I was always
trying to point these things out in a non-direct manner. And one of the
things I wanted to point out was this -- that at the very beginning we had
terribly important secrets; we'd worked out lots of stuff about bombs and
uranium and how it worked, and so on; and all this stuff was in documents
that were in wooden filing cabinets that had little, ordinary, common
padlocks on them. Of course, there were various things made by the shop,
like a rod that would go down and then a padlock to hold it, but it was
always just a padlock. Furthermore, you could get the stuff out without even
opening the padlock. You just tilt the cabinet over backwards. The bottom
drawer has a little rod that's supposed to hold the papers together, and
there's a long wide hole in the wood underneath. You can pull the papers out
from below.
So I used to pick the locks all the time and point out that it was very
easy to do. And every time we had a meeting of everybody together, I would
get up and say that we have important secrets and we shouldn't keep them in
such things; we need better locks. One day Teller got up at the meeting, and
he said to me, "I don't keep my most important secrets in my filing cabinet;
I keep them in my desk drawer. Isn't that better?"
I said, "I don't know. I haven't seen your desk drawer."
He was sitting near the front of the meeting, and I'm sitting further
back. So the meeting continues, and I sneak out and go down to see his desk
drawer.
I don't even have to pick the lock on the desk drawer. It turns out
that if you put your hand in the back, underneath, you can pull out the
paper like those toilet paper dispensers. You pull out one, it pulls
another, it pulls another... I emptied the whole damn drawer, put everything
away to one side, and went back upstairs.
The meeting was just ending, and everybody was coming out, and I joined
the crew and ran to catch up with Teller, and I said, "Oh, by the way, let
me see your desk drawer."
"Certainly," he said, and he showed me the desk.
I looked at it and said, "That looks pretty good to me. Let's see what
you have in there."
"I'll be very glad to show it to you," he said, putting in the key and
opening the drawer. "If," he said, "you hadn't already seen it yourself."
The trouble with playing a trick on a highly intelligent man like Mr.
Teller is that the time it takes him to figure out from the moment that he
sees there is something wrong till he understands exactly what happened is
too damn small to give you any pleasure!
Some of the special problems I had at Los Alamos were rather
interesting. One thing had to do with the safety of the plant at Oak Ridge,
Tennessee. Los Alamos was going to make the bomb, but at Oak Ridge they were
trying to separate the isotopes of uranium -- uranium 238 and uranium 235,
the explosive one. They were just beginning to get infinitesimal amounts
from an experimental thing of 235, and at the same time they were practicing
the chemistry. There was going to be a big plant, they were going to have
vats of the stuff, and then they were going to take the purified stuff and
repurify and get it ready for the next stage. (You have to purify it in
several stages.) So they were practicing on the one hand, and they were just
getting a little bit of U235 from one of the pieces of apparatus
experimentally on the other hand. And they were trying to learn how to assay
it, to determine how much uranium 235 there is in it. Though we would send
them instructions, they never got it right.
So finally Emil Segre said that the only possible way to get it right
was for him to go down there and see what they were doing. The army people
said, "No, it is our policy to keep all the information of Los Alamos at one
place."
The people in Oak Ridge didn't know anything about what it was to be
used for; they just knew what they were trying to do. I mean the higher
people knew they were separating uranium, but they didn't know how powerful
the bomb was, or exactly how it worked or anything. The people underneath
didn't know at all what they were doing. And the army wanted to keep it that
way. There was no information going back and forth. But Segre insisted
they'd never get the assays right, and the whole thing would go up in smoke.
So he finally went down to see what they were doing, and as he was walking
through he saw them wheeling a tank carboy of water, green water -- which is
uranium nitrate solution.
He said, "Uh, you're going to handle it like that when it's purified
too? Is that what you're going to do?"
They said, "Sure -- why not?"
"Won't it explode?" he said.
Huh! Explode?
Then the army said, "You see! We shouldn't have let any information get
to them! Now they are all upset."
It turned out that the army had realized how much stuff we needed to
make a bomb -- twenty kilograms or whatever it was -- and they realized that
this much material, purified, would never be in the plant, so there was no
danger. But they did not know that the neutrons were enormously more
effective when they are slowed down in water. In water it takes less than a
tenth -- no, a hundredth -- as much material to make a reaction that makes
radioactivity. It kills people around and so on. It was very dangerous, and
they had not paid any attention to the safety at all.
So a telegram goes from Oppenheimer to Segre: "Go through the entire
plant. Notice where all the concentrations are supposed to be, with the
process as they designed it. We will calculate in the meantime how much
material can come together before there's an explosion."
Two groups started working on it. Christy's group worked on water
solutions and my group worked on dry powder in boxes. We calculated about
how much material they could accumulate safely. And Christy was going to go
down and tell them all at Oak Ridge what the situation was, because this
whole thing is broken down and we have to go down and tell them now. So I
happily gave all my numbers to Christy and said, you have all the stuff, so
go. Christy got pneumonia; I had to go.
I had never traveled on an airplane before. They strapped the secrets
in a little thing on my back! The airplane in those days was like a bus,
except the stations were further apart. You stopped off every once in a
while to wait.
There was a guy standing there next to me swinging a chain, saying
something like, "It must be terribly difficult to fly without a priority on
airplanes these days."
I couldn't resist. I said, "Well, I don't know. I have a priority."
A little bit later he tried again. "There are some generals coming.
They are going to put off some of us number threes."
"It's all right," I said. "I'm a number two."
He probably wrote to his congressman -- if he wasn't a congressman
himself -- saying, "What are they doing sending these little kids around
with number two priorities in the middle of the war?"
At any rate, I arrived at Oak Ridge. The first thing I did was have
them take me to the plant, and I said nothing. I just looked at everything.
I found out that the situation was even worse than Segre reported, because
he noticed certain boxes in big lots in a room, but he didn't notice a lot
of boxes in another room on the other side of the same wall -- and things
like that. Now, if you have too much stuff together, it goes up, you see.
So I went through the entire plant. I have a very bad memory, but when
I work intensively I have a good short-term memory, and so I could remember
all kinds of crazy things like building 90-207, vat number so-and-so, and so
forth.
I went to my room that night, and went through the whole thing,
explained where all the dangers were, and what you would have to do to fix
this. It's rather easy. You put cadmium in solutions to absorb the neutrons
in the water, and you separate the boxes so they are not too dense,
according to certain rules.
The next day there was going to be a big meeting. I forgot to say that
before I left Los Alamos Oppenheimer said to me, "Now, the following people
are technically able down there at Oak Ridge: Mr. Julian Webb, Mr.
So-and-so, and so on. I want you to make sure that these people are at the
meeting, that you tell them how the thing can be made safe, so that they
really understand."
I said, "What if they're not at the meeting? What am I supposed to do?"
He said, "Then you should say: Los Alamos cannot accept the
responsibility for the safety of the Oak Ridge plant unless...!"
I said, "You mean me, little Richard, is going to go in there and say
--?"
He said, "Yes, little Richard, you go and do that."
I really grew up fast!
When I arrived, sure enough, the big shots in the company and the
technical people that I wanted were there, and the generals and everyone who
was interested in this very serious problem. That was good because the plant
would have blown up if nobody had paid attention to this problem.
There was a Lieutenant Zumwalt who took care of me. He told me that the
colonel said I shouldn't tell them how the neutrons work and all the details
because we want to keep things separate, so just tell them what to do to
keep it safe.
I said, "In my opinion it is impossible for them to obey a bunch of
rules unless they understand how it works. It's my opinion that it's only
going to work if I tell them, and Los Alamos cannot accept the
responsibility for the safety of the Oak Ridge plant unless they are fully
informed as to how it works!"
It was great. The lieutenant takes me to the colonel and repeats my
remark. The colonel says, "Just five minutes," and then he goes to the
window and he stops and thinks. That's what they're very good at -- making
decisions. I thought it was very remarkable how a problem of whether or not
information as to how the bomb works should be in the Oak Ridge plant had to
be decided and could be decided in five minutes. So I have a great deal of
respect for these military guys, because I never can decide anything very
important in any length of time at all.
In five minutes he said, "All right, Mr. Feynman, go ahead."
I sat down and I told them all about neutrons, how they worked, da da,
ta ta ta, there are too many neutrons together, you've got to keep the
material apart, cadmium absorbs, and slow neutrons are more effective than
fast neutrons, and yak yak -- all of which was elementary stuff at Los
Alamos, but they had never heard of any of it, so I appeared to be a
tremendous genius to them.
The result was that they decided to set up little groups to make their
own calculations to learn how to do it. They started to redesign plants, and
the designers of the plants were there, the construction designers, and
engineers, and chemical engineers for the new plant that was going to handle
the separated material.
They told me to come back in a few months, so I came back when the
engineers had finished the design of the plant. Now it was for me to look at
the plant.
How do you look at a plant that isn't built yet? I don't know.
Lieutenant Zumwalt, who was always coming around with me because I had to
have an escort everywhere, takes me into this room where there are these two
engineers and a loooooong table covered with a stack of blueprints
representing the various floors of the proposed plant.
I took mechanical drawing when I was in school, but I am not good at
reading blueprints. So they unroll the stack of blueprints and start to
explain it to me, thinking I am a genius. Now, one of the things they had to
avoid in the plant was accumulation. They had problems like when there's an
evaporator working, which is trying to accumulate the stuff, if the valve
gets stuck or something like that and too much stuff accumulates, it'll
explode. So they explained to me that this plant is designed so that if any
one valve gets stuck nothing will happen. It needs at least two valves
everywhere.
Then they explain how it works. The carbon tetrachloride comes in here,
the uranium nitrate from here comes in here, it goes up and down, it goes up
through the floor, comes up through the pipes, coming up from the second
floor, bluuuuurp -- going through the stack of blueprints, down-up-down-up,
talking very fast, explaining the very, very complicated chemical plant.
I'm completely dazed. Worse, I don't know what the symbols on the
blueprint mean! There is some kind of a thing that at first I think is a
window. It's a square with a little cross in the middle, all over the damn
place. I think it's a window, but no, it can't be a window, because it isn't
always at the edge. I want to ask them what it is.
You must have been in a situation like this when you didn't ask them
right away. Right away it would have been OK. But now they've been talking a
little bit too long. You hesitated too long. If you ask them now they'll
say, "What are you wasting my time all this time for?"
What am I going to do? I get an idea. Maybe it's a valve. I take my
finger and I put it down on one of the mysterious little crosses in the
middle of one of the blueprints on page three, and I say, "What happens if
this valve gets stuck?" -- figuring they're going to say, "That's not a
valve, sir, that's a window."
So one looks at the other and says, "Well, if that valve gets stuck --"
and he goes up and down on the blueprint, up and down, the other guy goes up
and down, back and forth, back and forth, and they both look at each other.
They turn around to me and they open their mouths like astonished fish and
say, "You're absolutely right, sir."
So they rolled up the blueprints and away they went and we walked out.
And Mr. Zumwalt, who had been following me all the way through, said,
"You're a genius. I got the idea you were a genius when you went through the
plant once and you could tell them about evaporator C-21 in building 90-207
the next morning," he says, "but what you have just done is so fantastic I
want to know how, how do you do that?"
I told him you try to find out whether it's a valve or not.
Another kind of problem I worked on was this. We had to do lots of
calculations, and we did them on Marchant calculating machines. By the way,
just to give you an idea of what Los Alamos was like: We had these Marchant
computers -- hand calculators with numbers. You push them, and they
multiply, divide, add, and so on, but not easy like they do now. They were
mechanical gadgets, failing often, and they had to be sent back to the
factory to be repaired. Pretty soon you were running out of machines. A few
of us started to take the covers off (We weren't supposed to. The rules
read: "You take the covers off, we cannot be responsible...") So we took the
covers off and we got a nice series of lessons on how to fix them, and we
got better and better at it as we got more and more elaborate repairs. When
we got something too complicated, we sent it back to the factory, but we'd
do the easy ones and kept the things going. I ended up doing all the
computers and there was a guy in the machine shop who took care of
typewriters.
Anyway, we decided that the big problem -- which was to figure out
exactly what happened during the bomb's implosion, so you can figure out
exactly how much energy was released and so on -- required much more
calculating than we were capable of. A clever fellow by the name of Stanley
Frankel realized that it could possibly be done on IBM machines. The IBM
company had machines for business purposes, adding machines called
tabulators for listing sums, and a multiplier that you put cards in and it
would take two numbers from a card and multiply them. There were also
collators and sorters and so on.
So Frankel figured out a nice program. If we got enough of these
machines in a room, we could take the cards and put them through a cycle.
Everybody who does numerical calculations now knows exactly what I'm talking
about, but this was kind of a new thing then -- mass production with
machines. We had done things like this on adding machines. Usually you go
one step across, doing everything yourself. But this was different -- where
you go first to the adder, then to the multiplier, then to the adder, and so
on. So Frankel designed this system and ordered the machines from the IBM
company, because we realized it was a good way of solving our problems.
We needed a man to repair the machines, to keep them going and
everything. And the army was always going to send this fellow they had, but
he was always delayed. Now, we always were in a hurry. Everything we did, we
tried to do as quickly as possible. In this particular case, we worked out
all the numerical steps that the machines were supposed to do -- multiply
this, and then do this, and subtract that. Then we worked out the program,
but we didn't have any machine to test it on. So we set up this room with
girls in it. Each one had a Marchant: one was the multiplier, another was
the adder. This one cubed -- all she did was cube a number on an index card
and send it to the next girl.
We went through our cycle this way until we got all the bugs out. It
turned out that the speed at which we were able to do it was a hell of a lot
faster than the other way, where every single person did all the steps. We
got speed with this system that was the predicted speed for the IBM machine.
The only difference is that the IBM machines didn't get tired and could work
three shifts. But the girls got tired after a while.
Anyway, we got the bugs out during this process, and finally the
machines arrived, but not the repairman. These were some of the most
complicated machines of the technology of those days, big things that came
partially disassembled, with lots of wires and blueprints of what to do. We
went down and we put them together, Stan Frankel and I and another fellow,
and we had our troubles. Most of the trouble was the big shots coming in all
the time and saying, "You're going to break something!"
We put them together, and sometimes they would work, and sometimes they
were put together wrong and they didn't work. Finally I was working on some
multiplier and I saw a bent part inside, but I was afraid to straighten it
because it might snap off -- and they were always telling us we were going
to bust something irreversibly. When the repairman finally got there, he
fixed the machines we hadn't got ready, and everything was going. But he had
trouble with the one that I had had trouble with. After three days he was
still working on that one last machine.
I went down. I said, "Oh, I noticed that was bent."
He said, "Oh, of course. That's all there is to it!" Bend! It was all
right. So that was it.
Well, Mr. Frankel, who started this program, began to suffer from the
computer disease that anybody who works with computers now knows about. It's
a very serious disease and it interferes completely with the work. The
trouble with computers is you play with them. They are so wonderful. You
have these switches -- if it's an even number you do this, if it's an odd
number you do that -- and pretty soon you can do more and more elaborate
things if you are clever enough, on one machine.
After a while the whole system broke down. Frankel wasn't paying any
attention; he wasn't supervising anybody. The system was going very, very
slowly --while he was sitting in a room figuring out how to make one
tabulator automatically print arc-tangent X, and then it would start and it
would print columns and then bitsi, bitsi, bitsi, and calculate the
arc-tangent automatically by integrating as it went along and make a whole
table in one operation.
Absolutely useless. We had tables of arc-tangents. But if you've ever
worked with computers, you understand the disease -- the delight in being
able to see how much you can do. But he got the disease for the first time,
the poor fellow who invented the thing.
I was asked to stop working on the stuff I was doing in my group and go
down and take over the IBM group, and I tried to avoid the disease. And,
although they had done only three problems in nine months, I had a very good
group.
The real trouble was that no one had ever told these fellows anything.
The army had selected them from all over the country for a thing called
Special Engineer Detachment -- clever boys from high school who had
engineering ability. They sent them up to Los Alamos. They put them in
barracks. And they would tell them nothing.
Then they came to work, and what they had to do was work on IBM
machines -- punching holes, numbers that they didn't understand. Nobody told
them what it was. The thing was going very slowly. I said that the first
thing there has to be is that these technical guys know what we're doing.
Oppenheimer went and talked to the security and got special permission so I
could give a nice lecture about what we were doing, and they were all
excited: "We're fighting a war! We see what it is!" They knew what the
numbers meant. If the pressure came out higher, that meant there was more
energy released, and so on and so on. They knew what they were doing.
Complete transformation! They began