en something passed a photocell. I'd play around with selenium; I
was piddling around all the time. I did calculate a little bit for the lamp
bank, a series of switches and bulbs I used as resistors to control
voltages. But all that was for application. I never did any laboratory kind
of experiments.
I also had a microscope and loved to watch things under the microscope.
It took patience: I would get something under the microscope and I would
watch it interminably. I saw many interesting things, like everybody sees --
a diatom slowly making its way across the slide, and so on.
One day I was watching a paramecium and I saw something that was not
described in the books I got in school -- in college, even. These books
always simplify things so the world will be more like they want it to be:
When they're talking about the behavior of animals, they always start out
with, "The paramecium is extremely simple; it has a simple behavior. It
turns as its slipper shape moves through the water until it hits something,
at which time it recoils, turns through an angle, and then starts out
again."
It isn't really right. First of all, as everybody knows, the paramecia,
from time to time, conjugate with each other -- they meet and exchange
nuclei. How do they decide when it's time to do that? (Never mind; that's
not my observation.)
I watched these paramecia hit something, recoil, turn through an angle,
and go again. The idea that it's mechanical, like a computer program -- it
doesn't look that way. They go different distances, they recoil different
distances, they turn through angles that are different in various cases;
they don't always turn to the right; they're very irregular. It looks
random, because you don't know what they're hitting; you don't know all the
chemicals they're smelling, or what.
One of the things I wanted to watch was what happens to the paramecium
when the water that it's in dries up. It was claimed that the paramecium can
dry up into a sort of hardened seed. I had a drop of water on the slide
under my microscope, and in the drop of water was a paramecium and some
"grass" -- at the scale of the paramecium, it looked like a network of
jackstraws. As the drop of water evaporated, over a time of fifteen or
twenty minutes, the paramecium got into a tighter and tighter situation:
there was more and more of this back-and-forth until it could hardly move.
It was stuck between these "sticks," almost jammed.
Then I saw something I had never seen or heard of: the paramecium lost
its shape. It could flex itself, like an amoeba. It began to push itself
against one of the sticks, and began dividing into two prongs until the
division was about halfway up the paramecium, at which time it decided that
wasn't a very good idea, and backed away.
So my impression of these animals is that their behavior is much too
simplified in the books. It is not so utterly mechanical or one-dimensional
as they say. They should describe the behavior of these simple animals
correctly. Until we see how many dimensions of behavior even a one-celled
animal has, we won't be able to fully understand the behavior of more
complicated animals.
I also enjoyed watching bugs. I had an insect book when I was about
thirteen. It said that dragonflies are not harmful; they don't sting. In our
neighborhood it was well known that "darning needles," as we called them,
were very dangerous when they'd sting. So if we were outside somewhere
playing baseball, or something, and one of these things would fly around,
everybody would run for cover, waving their arms, yelling, "A darning
needle! A darning needle!"
So one day I was on the beach, and I'd just read this book that said
dragonflies don't sting. A darning needle came along, and everybody was
screaming and running around, and I just sat there. "Don't worry!" I said.
"Darning needles don't sting!"
The thing landed on my foot. Everybody was yelling and it was a big
mess, because this darning needle was sitting on my foot. And there I was,
this scientific wonder, saying it wasn't going to sting me.
You're sure this is a story that's going to come out that it stings me
-- but it didn't. The book was right. But I did sweat a bit.
I also had a little hand microscope. It was a toy microscope, and I
pulled the magnification piece out of it, and would hold it in my hand like
a magnifying glass, even though it was a microscope of forty or fifty power.
With care you could hold the focus. So I could go around and look at things
right out in the street.
So when I was in graduate school at Princeton, I once took it out of my
pocket to look at some ants that were crawling around on some ivy. I had to
exclaim out loud, I was so excited. What I saw was an ant and an aphid,
which ants take care of -- they carry them from plant to plant if the plant
they're on is dying. In return the ants get partially digested aphid juice,
called "honeydew." I knew that; my father had told me about it, but I had
never seen it.
So here was this aphid and sure enough, an ant came along, and patted
it with its feet -- all around the aphid, pat, pat, pat, pat, pat. This was
terribly exciting! Then the juice came out of the back of the aphid. And
because it was magnified, it looked like a big, beautiful, glistening ball,
like a balloon, because of the surface tension. Because the microscope
wasn't very good, the drop was colored a little bit from chromatic
aberration in the lens -- it was a gorgeous thing!
The ant took this ball in its two front feet, lifted it off the aphid,
and held it. The world is so different at that scale that you can pick up
water and hold it! The ants probably have a fatty or greasy material on
their legs that doesn't break the surface tension of the water when they
hold it up. Then the ant broke the surface of the drop with its mouth, and
the surface tension collapsed the drop right into his gut. It was very
interesting to see this whole thing happen!
In my room at Princeton I had a bay window with a U-shaped windowsill.
One day some ants came out on the windowsill and wandered around a little
bit. I got curious as to how they found things. I wondered, how do they know
where to go? Can they tell each other where food is, like bees can? Do they
have any sense of geometry?
This is all amateurish; everybody knows the answer, but I didn't know
the answer, so the first thing I did was to stretch some string across the U
of the bay window and hang a piece of folded cardboard with sugar on it from
the string. The idea of this was to isolate the sugar from the ants, so they
wouldn't find it accidentally. I wanted to have everything under control.
Next I made a lot of little strips of paper and put a fold in them, so
I could pick up ants and ferry them from one place to another. I put the
folded strips of paper in two places: Some were by the sugar (hanging from
the string), and the others were near the ants in a particular location. I
sat there all afternoon, reading and watching, until an ant happened to walk
onto one of my little paper ferries. Then I took him over to the sugar.
After a few ants had been ferried over to the sugar, one of them
accidentally walked onto one of the ferries nearby, and I carried him back.
I wanted to see how long it would take the other ants to get the
message to go to the "ferry terminal." It started slowly, but rapidly
increased until I was going mad ferrying the ants back and forth.
But suddenly, when everything was going strong, I began to deliver the
ants from the sugar to a different spot. The question now was, does the ant
learn to go back to where it just came from, or does it go where it went the
time before?
After a while there were practically no ants going to the first place
(which would take them to the sugar), whereas there were many ants at the
second place, milling around, trying to find the sugar. So I figured out so
far that they went where they just came from.
In another experiment, I laid out a lot of glass microscope slides, and
got the ants to walk on them, back and forth, to some sugar I put on the
windowsill. Then, by replacing an old slide with a new one, or by
rearranging the slides, I could demonstrate that the ants had no sense of
geometry: they couldn't figure out where something was. If they went to the
sugar one way, and there was a shorter way back, they would never figure out
the short way.
It was also pretty clear from rearranging the glass slides that the
ants left some sort of trail. So then came a lot of easy experiments to find
out how long it takes a trail to dry up, whether it can be easily wiped off,
and so on. I also found out the trail wasn't directional. If I'd pick up an
ant on a piece of paper, turn him around and around, and then put him back
onto the trail, he wouldn't know that he was going the wrong way until he
met another ant. (Later, in Brazil, I noticed some leaf-cutting ants and
tried the same experiment on them. They could tell, within a few steps,
whether they were going toward the food or away from it -- presumably from
the trail, which might be a series of smells in a pattern: A, B, space, A,
B, space, and so on.)
I tried at one point to make the ants go around in a circle, but I
didn't have enough patience to set it up. I could see no reason, other than
lack of patience, why it couldn't be done.
One thing that made experimenting difficult was that breathing on the
ants made them scurry. It must be an instinctive thing against some animal
that eats them or disturbs them. I don't know if it was the warmth, the
moisture, or the smell of my breath that bothered them, but I always had to
hold my breath and kind of look to one side so as not to confuse the
experiment while I was ferrying the ants.
One question that I wondered about was why the ant trails look so
straight and nice. The ants look as if they know what they're doing, as if
they have a good sense of geometry. Yet the experiments that I did to try to
demonstrate their sense of geometry didn't work.
Many years later, when I was at Caltech and lived in a little house on
Alameda Street, some ants came out around the bathtub. I thought, "This is a
great opportunity." I put some sugar on the other end of the bathtub, and
sat there the whole afternoon until an ant finally found the sugar. It's
only a question of patience.
The moment the ant found the sugar, I picked up a colored pencil that I
had ready (I had previously done experiments indicating that the ants don't
give a damn about pencil marks -- they walk right over them -- so I knew I
wasn't disturbing anything), and behind where the ant went I drew a line so
I could tell where his trail was. The ant wandered a little bit wrong to get
back to the hole, so the line was quite wiggly, unlike a typical ant trail.
When the next ant to find the sugar began to go back, I marked his
trail with another color. (By the way, he followed the first ant's return
trail back, rather than his own incoming trail. My theory is that when an
ant has found some food, he leaves a much stronger trail than when he's just
wandering around.)
This second ant was in a great hurry and followed, pretty much, the
original trail. But because he was going so fast he would go straight out,
as if he were coasting, when the trail was wiggly. Often, as the ant was
"coasting," he would find the trail again. Already it was apparent that the
second ant's return was slightly straighter. With successive ants the same
"improvement" of the trail by hurriedly and carelessly "following" it
occurred.
I followed eight or ten ants with my pencil until their trails became a
neat line right along the bathtub. It's something like sketching: You draw a
lousy line at first; then you go over it a few times and it makes a nice
line after a while.
I remember that when I was a kid my father would tell me how wonderful
ants are, and how they cooperate. I would watch very carefully three or four
ants carrying a little piece of chocolate back to their nest. At first
glance it looks like efficient, marvelous, brilliant cooperation. But if you
look at it carefully, you'll see that it's nothing of the kind: They're all
behaving as if the chocolate is held up by something else. They pull at it
one way or the other way. An ant may crawl over it while it's being pulled
at by the others. It wobbles, it wiggles, the directions are all confused.
The chocolate doesn't move in a nice way toward the nest.
The Brazilian leaf-cutting ants, which are otherwise so marvelous, have
a very interesting stupidity associated with them that I'm surprised hasn't
evolved out. It takes considerable work for the ant to cut the circular arc
in order to get a piece of leaf. When the cutting is done, there's a
fifty-fifty chance that the ant will pull on the wrong side, letting the
piece he just cut fall to the ground. Half the time, the ant will yank and
pull and yank and pull on the wrong part of the leaf, until it gives up and
starts to cut another piece. There is no attempt to pick up a piece that it,
or any other ant, has already cut. So it's quite obvious, if you watch very
carefully, that it's not a brilliant business of cutting leaves and carrying
them away; they go to a leaf, cut an arc, and pick the wrong side half the
time while the right piece falls down.
In Princeton the ants found my larder, where I had jelly and bread and
stuff, which was quite a distance from the window. A long line of ants
marched along the floor across the living room. It was during the time I was
doing these experiments on the ants, so I thought to myself, "What can I do
to stop them from coming to my larder without killing any ants? No poison;
you gotta be humane to the ants!"
What I did was this: In preparation, I put a bit of sugar about six or
eight inches from their entry point into the room, that they didn't know
about. Then I made those ferry things again, and whenever an ant returning
with food walked onto my little ferry, I'd carry him over and put him on the
sugar. Any ant coming toward the larder that walked onto a ferry I also
carried over to the sugar. Eventually the ants found their way from the
sugar to their hole, so this new trail was being doubly reinforced, while
the old trail was being used less and less. I knew that after half an hour
or so the old trail would dry up, and in an hour they were out of my larder.
I didn't wash the floor; I didn't do anything but ferry ants.
--------
Part 3
Feynman, the Bomb, and the Military
--------
Fizzled Fuses
When the war began in Europe but had not yet been declared in the
United States, there was a lot of talk about getting ready and being
patriotic. The newspapers had big articles on businessmen volunteering to go
to Plattsburg, New York, to do military training, and so on.
I began to think I ought to make some kind of contribution, too. After
I finished up at MIT, a friend of mine from the fraternity, Maurice Meyer,
who was in the Army Signal Corps, took me to see a colonel at the Signal
Corps offices in New York.
"I'd like to aid my country, sir, and since I'm technically-minded,
maybe there's a way I could help."
"Well, you'd better just go up to Plattsburg to boot camp and go
through basic training. Then we'll be able to use you," the colonel said.
"But isn't there some way to use my talent more directly?"
"No; this is the way the army is organized. Go through the regular
way."
I went outside and sat in the park to think about it. I thought and
thought: Maybe the best way to make a contribution is to go along with their
way. But fortunately, I thought a little more, and said, "To hell with it!
I'll wait awhile. Maybe something will happen where they can use me more
effectively."
I went to Princeton to do graduate work, and in the spring I went once
again to the Bell Labs in New York to apply for a summer job. I loved to
tour the Bell Labs. Bill Shockley, the guy who invented transistors, would
show me around. I remember somebody's room where they had marked a window:
The George Washington Bridge was being built, and these guys in the lab were
watching its progress. They had plotted the original curve when the main
cable was first put up, and they could measure the small differences as the
bridge was being suspended from it, as the curve turned into a parabola. It
was just the kind of thing I would like to be able to think of doing. I
admired those guys; I was always hoping I could work with them one day.
Some guys from the lab took me out to this seafood restaurant for
lunch, and they were all pleased that they were going to have oysters. I
lived by the ocean and I couldn't look at this stuff; I couldn't eat fish,
let alone oysters.
I thought to myself, "I've gotta be brave. I've gotta eat an oyster."
I took an oyster, and it was absolutely terrible. But I said to myself,
"That doesn't really prove you're a man. You didn't know how terrible it was
gonna be. It was easy enough when it was uncertain."
The others kept talking about how good the oysters were, so I had
another oyster, and that was really harder than the first one.
This time, which must have been my fourth or fifth time touring the
Bell Labs, they accepted me. I was very happy. In those days it was hard to
find a job where you could be with other scientists.
But then there was a big excitement at Princeton. General Trichel from
the army came around and spoke to us; "We've got to have physicists!
Physicists are very important to us in the army! We need three physicists!"
You have to understand that, in those days, people hardly knew what a
physicist was. Einstein was known as a mathematician, for instance -- so it
was rare that anybody needed physicists. I thought, "This is my opportunity
to make a contribution," and I volunteered to work for the army.
I asked the Bell Labs if they would let me work for the army that
summer, and they said they had war work, too, if that was what I wanted. But
I was caught up in a patriotic fever and lost a good opportunity. It would
have been much smarter to work in the Bell Labs. But one gets a little silly
during those times.
I went to the Frankfort Arsenal, in Philadelphia, and worked on a
dinosaur: a mechanical computer for directing artillery. When airplanes flew
by, the gunners would watch them in a telescope, and this mechanical
computer, with gears and cams and so forth, would try to predict where the
plane was going to be. It was a most beautifully designed and built machine,
and one of the important ideas in it was non-circular gears -- gears that
weren't circular, but would mesh anyway. Because of the changing radii of
the gears, one shaft would turn as a function of the other. However, this
machine was at the end of the line. Very soon afterwards, electronic
computers came in.
After saying all this stuff about how physicists were so important to
the army, the first thing they had me doing was checking gear drawings to
see if the numbers were right. This went on for quite a while. Then,
gradually, the guy in charge of the department began to see I was useful for
other things, and as the summer went on, he would spend more time discussing
things with me.
One mechanical engineer at Frankfort was always trying to design things
and could never get everything right. One time he designed a box full of
gears, one of which was a big, eight-inch-diameter gear wheel that had six
spokes. The fella says excitedly, "Well, boss, how is it? How is it?"
"Just fine!" the boss replies. "All you have to do is specify a shaft
passer on each of the spokes, so the gear wheel can turn!" The guy had
designed a shaft that went right between the spokes!
The boss went on to tell us that there was such a thing as a shaft
passer (I thought he must have been joking). It was invented by the Germans
during the war to keep the British minesweepers from catching the cables
that held the German mines floating under water at a certain depth. With
these shaft passers, the German cables could allow the British cables to
pass through as if they were going through a revolving door. So it was
possible to put shaft passers on all the spokes, but the boss didn't mean
that the machinists should go to all that trouble; the guy should instead
just redesign it and put the shaft somewhere else.
Every once in a while the army sent down a lieutenant to check on how
things were going. Our boss told us that since we were a civilian section,
the lieutenant was higher in rank than any of us. "Don't tell the lieutenant
anything," he said. "Once he begins to think he knows what we're doing,
he'll be giving us all kinds of orders and screwing everything up."
By that time I was designing some things, but when the lieutenant came
by, I pretended I didn't know what I was doing, that I was only following
orders.
"What are you doing here, Mr. Feynman?"
"Well, I draw a sequence of lines at successive angles, and then I'm
supposed to measure out from the center different distances according to
this table, and lay it out..."
"Well, what is it?"
"I think it's a cam." I had actually designed the thing, but I acted as
if somebody had just told me exactly what to do.
The lieutenant couldn't get any information from anybody, and we went
happily along, working on this mechanical computer, without any
interference.
One day the lieutenant came by, and asked us a simple question:
"Suppose that the observer is not at the same location as the gunner -- how
do you handle that?"
We got a terrible shock. We had designed the whole business using polar
coordinates, using angles and the radius distance. With X and Y coordinates,
it's easy to correct for a displaced observer. It's simply a matter of
addition or subtraction. But with polar coordinates, it's a terrible mess!
So it turned out that this lieutenant whom we were trying to keep from
telling us anything ended up telling us something very important that we had
forgotten in the design of this device: the possibility that the gun and the
observing station are not at the same place! It was a big mess to fix it.
Near the end of the summer I was given my first real design job: a machine
that would make a continuous curve out of a set of points -- one point
coming in every fifteen seconds -- from a new invention developed in England
for tracking airplanes, called "radar." It was the first time I had ever
done any mechanical designing, so I was a little bit frightened.
I went over to one of the other guys and said, "You're a mechanical
engineer; I don't know how to do any mechanical engineering, and I just got
this job..."
"There's nothin' to it," he said. "Look, I'll show you. There's two
rules you need to know to design these machines. First, the friction in
every bearing is so-and-so much, and in every gear junction, so-and-so much.
From that, you can figure out how much force you need to drive the thing.
Second, when you have a gear ratio, say 2 to 1, and you are wondering
whether you should make it 10 to 5 or 24 to 12 or 48 to 24, here's how to
decide: You look in the Boston Gear Catalogue, and select those gears that
are in the middle of the list. The ones at the high end have so many teeth
they're hard to make, if they could make gears with even finer teeth, they'd
have made the list go even higher. The gears at the low end of the list have
so few teeth they break easy. So the best design uses gears from the middle
of the list."
I had a lot of fun designing that machine. By simply selecting the
gears from the middle of the list and adding up the little torques with the
two numbers he gave me, I could be a mechanical engineer!
The army didn't want me to go back to Princeton to work on my degree
after that summer. They kept giving me this patriotic stuff, and offered a
whole project that I could run, if I would stay.
The problem was to design a machine like the other one -- what they
called a director -- but this time I thought the problem was easier, because
the gunner would be following behind in another airplane at the same
altitude. The gunner would set into my machine his altitude and an estimate
of his distance behind the other airplane. My machine would automatically
tilt the gun up at the correct angle and set the fuse.
As director of this project, I would be making trips down to Aberdeen
to get the firing tables. However, they already had some preliminary data. I
noticed that for most of the higher altitudes where these airplanes would be
flying, there wasn't any data. So I called up to find out why there wasn't
any data and it turned out that the fuses they were going to use were not
clock fuses, but powder-train fuses, which didn't work at those altitudes --
they fizzled out in the thin air.
I thought I only had to correct the air resistance at different
altitudes. Instead, my job was to invent a machine that would make the shell
explode at the right moment, when the fuse won't burn!
I decided that was too hard for me and went back to Princeton.
--------
Testing Bloodhounds
When I was at Los Alamos and would get a little time off, I would often
go visit my wife, who was in a hospital in Albuquerque, a few hours away.
One time I went to visit her and couldn't go in right away, so I went to the
hospital library to read.
I read an article in Science about bloodhounds, and how they could
smell so very well. The authors described the various experiments that they
did -- the bloodhounds could identify which items had been touched by
people, and so on -- and I began to think: It is very remarkable how good
bloodhounds are at smelling, being able to follow trails of people, and so
forth, but how good are we, actually?
When the time came that I could visit my wife, I went to see her, and I
said, "We're gonna do an experiment. Those Coke bottles over there (she had
a six-pack of empty Coke bottles that she was saving to send out) -- now you
haven't touched them in a couple of days, right?"
"That's right."
I took the six-pack over to her without touching the bottles, and said,
"OK. Now I'll go out, and you take out one of the bottles, handle it for
about two minutes, and then put it back. Then I'll come in, and try to tell
which bottle it was."
So I went out, and she took out one of the bottles and handled it for
quite a while -- lots of time, because I'm no bloodhound! According to the
article, they could tell if you just touched it.
Then I came back, and it was absolutely obvious! I didn't even have to
smell the damn thing, because, of course, the temperature was different. And
it was also obvious from the smell. As soon as you put it up near your face,
you could smell it was dampish and warmer. So that experiment didn't work
because it was too obvious.
Then I looked at the bookshelf and said, "Those books you haven't
looked at for a while, right? This time, when I go out, take one book off
the shelf, and just open it -- that's all -- and close it again; then put it
back."
So I went out again, she took a book, opened it and closed it, and put
it back. I came in -- and nothing to it! It was easy. You just smell the
books. It's hard to explain, because we're not used to saying things about
it. You put each book up to your nose and sniff a few times, and you can
tell. It's very different. A book that's been standing there a while has a
dry, uninteresting kind of smell. But when a hand has touched it, there's a
dampness and a smell that's very distinct.
We did a few more experiments, and I discovered that while bloodhounds
are indeed quite capable, humans are not as incapable as they think they
are: it's just that they carry their nose so high off the ground!
(I've noticed that my dog can correctly tell which way I've gone in the
house, especially if I'm barefoot, by smelling my footprints. So I tried to
do that: I crawled around the rug on my hands and knees, sniffing, to see if
I could tell the difference between where I walked and where I didn't, and I
found it impossible. So the dog is much better than I am.)
Many years later, when I was first at Caltech, there was a party at
Professor Bacher's house, and there were a lot of people from Caltech. I
don't know how it came up, but I was telling them this story about smelling
the bottles and the books. They didn't believe a word, naturally, because
they always thought I was a faker. I had to demonstrate it.
We carefully took eight or nine books off the shelf without touching
them directly with our hands, and then I went out. Three different people
touched three different books: they picked one up, opened it, closed it, and
put it back.
Then I came back, and smelled everybody's hands, and smelled all the
books -- I don't remember which I did first -- and found all three books
correctly; I got one person wrong.
They still didn't believe me; they thought it was some sort of magic
trick. They kept trying to figure out how I did it. There's a famous trick
of this kind, where you have a confederate in the group who gives you
signals as to what it is, and they were trying to figure out who the
confederate was. Since then I've often thought that it would be a good card
trick to take a deck of cards and tell someone to pick a card and put it
back, while you're in the other room. You say, "Now I'm going to tell you
which card it is, because I'm a bloodhound: I'm going to smell all these
cards and tell you which card you picked." Of course, with that kind of
patter, people wouldn't believe for a minute that that's what you were
actually doing!
People's hands smell very different -- that's why dogs can identify
people; you have to try it! All hands have a sort of moist smell, and a
person who smokes has a very different smell on his hands from a person who
doesn't; ladies often have different kinds of perfumes, and so on. If
somebody happened to have some coins in his pocket and happened to be
handling them, you can smell that.
--------
Los Alamos from Below*
* Adapted from a talk given in the First Annual Santa Barbara Lectures
on Science and Society at the University of California at Santa Barbara in
1975. "Los Alamos from Below" was one of nine lectures in a series published
as Reminiscences of Los Alamos, 1943-1945, edited by L. Badash et al., pp.
105-132. Copyright (c) 1980 by D. Reidel Publishing Company, Dordrecht,
Holland.
When I say "Los Alamos from below," I mean that. Although in my field
at the present time I'm a slightly famous man, at that time I was not
anybody famous at all. I didn't even have a degree when I started to work
with the Manhattan Project. Many of the other people who tell you about Los
Alamos -- people in higher echelons -- worried about some big decisions. I
worried about no big decisions. I was always flittering about underneath.
I was working in my room at Princeton one day when Bob Wilson came in
and said that he had been funded to do a job that was a secret, and he
wasn't supposed to tell anybody, but he was going to tell me because he knew
that as soon as I knew what he was going to do, I'd see that I had to go
along with it. So he told me about the problem of separating different
isotopes of uranium to ultimately make a bomb. He had a process for
separating the isotopes of uranium (different from the one which was
ultimately used) that he wanted to try to develop. He told me about it, and
he said, "There's a meeting..."
I said I didn't want to do it.
He said, "All right, there's a meeting at three o'clock. I'll see you
there."
I said, "It's all right that you told me the secret because I'm not
going to tell anybody, but I'm not going to do it."
So I went back to work on my thesis -- for about three minutes. Then I
began to pace the floor and think about this thing. The Germans had Hitler
and the possibility of developing an atomic bomb was obvious, and the
possibility that they would develop it before we did was very much of a
fright. So I decided to go to the meeting at three o'clock.
By four o'clock I already had a desk in a room and was trying to
calculate whether this particular method was limited by the total amount of
current that you get in an ion beam, and so on. I won't go into the details.
But I had a desk, and I had paper, and I was working as hard as I could and
as fast as I could, so the fellas who were building the apparatus could do
the experiment right there.
It was like those moving pictures where you see a piece of equipment go
bruuuuup, bruuuuup, bruuuuup. Every time I'd look up, the thing was getting
bigger. What was happening, of course, was that all the boys had decided to
work on this and to stop their research in science. All science stopped
during the war except the little bit that was done at Los Alamos. And that
was not much science; it was mostly engineering.
All the equipment from different research projects was being put
together to make the new apparatus to do the experiment -- to try to
separate the isotopes of uranium. I stopped my own work for the same reason,
though I did take a six-week vacation after a while and finished writing my
thesis. And I did get my degree just before I got to Los Alamos -- so I
wasn't quite as far down the scale as I led you to believe.
One of the first interesting experiences I had in this project at
Princeton was meeting great men. I had never met very many great men before.
But there was an evaluation committee that had to try to help us along, and
help us ultimately decide which way we were going to separate the uranium.
This committee had men like Compton and Tolman and Smyth and Urey and Rabi
and Oppenheimer on it. I would sit in because I understood the theory of how
our process of separating isotopes worked, and so they'd ask me questions
and talk about it. In these discussions one man would make a point. Then
Compton, for example, would explain a different point of view. He would say
it should be this way, and he was perfectly right. Another guy would say,
well, maybe, but there's this other possibility we have to consider against
it.
So everybody is disagreeing, all around the table. I am surprised and
disturbed that Compton doesn't repeat and emphasize his point. Finally, at
the end, Tolman, who's the chairman, would say, "Well, having heard all
these arguments, I guess it's true that Compton's argument is the best of
all, and now we have to go ahead."
It was such a shock to me to see that a committee of men could present
a whole lot of ideas, each one thinking of a new facet, while remembering
what the other fella said, so that, at the end, the decision is made as to
which idea was the best -- summing it all up -- without having to say it
three times. These were very great men indeed.
It was ultimately decided that this project was not to be the one they
were going to use to separate uranium. We were told then that we were going
to stop, because in Los Alamos, New Mexico, they would be starting the
project that would actually make the bomb. We would all go out there to make
it. There would be experiments that we would have to do, and theoretical
work to do. I was in the theoretical work. All the rest of the fellas were
in experimental work.
The question was -- What to do now? Los Alamos wasn't ready yet. Bob
Wilson tried to make use of this time by, among other things, sending me to
Chicago to find out all that we could find out about the bomb and the
problems. Then, in our laboratories, we could start to build equipment,
counters of various kinds, and so on, that would be useful when we got to
Los Alamos. So no time was wasted.
I was sent to Chicago with the instructions to go to each group, tell
them I was going to work with them, and have them tell me about a problem in
enough detail that I could actually sit down and start to work on it. As
soon as I got that far, I was to go to another guy and ask for another
problem. That way I would understand the details of everything.
It was a very good idea, but my conscience bothered me a little bit
because they would all work so hard to explain things to me, and I'd go away
without helping them. But I was very lucky. When one of the guys was
explaining a problem, I said, "Why don't you do it by differentiating under
the integral sign?" In half an hour he had it solved, and they'd been
working on it for three months. So, I did something, using my "different box
of tools." Then I came back from Chicago, and I described the situation --
how much energy was released, what the bomb was going to be like, and so
forth.
I remember a friend of mine who worked with me, Paul Olum, a
mathematician, came up to me afterwards and said, "When they make a moving
picture about this, they'll have the guy coming back from Chicago to make
his report to the Princeton men about the bomb. He'll be wearing a suit and
carrying a briefcase and so on -- and here you're in dirty shirtsleeves and
just telling us all about it, in spite of its being such a serious and
dramatic thing."
There still seemed to be a delay, and Wilson went to Los Alamos to find
out what was holding things up. When he got there, he found that the
construction company was working very hard and had finished the theater, and
a few other buildings that they understood, but they hadn't gotten
instructions clear on how to build a laboratory -- how many pipes for gas,
how much for water. So Wilson simply stood around and decided, then and
there, how much water, how much gas, and so on, and told them to start
building the laboratories.
When he came back to us, we were all ready to go and we were getting
impatient. So they all got together and decided we'd go out there anyway,
even though it wasn't ready.
We were recruited, by the way, by Oppenheimer and other people, and he
was very patient. He paid attention to everybody's problems. He worried
about my wife, who had TB, and whether there would be a hospital out there,
and everything. It was the first time I met him in such a personal way; he
was a wonderful man.
We were told to be very careful -- not to buy our train ticket in
Princeton, for example, because Princeton was a very small station, and if
everybody bought train tickets to Albuquerque, New Mexico, in Princeton,
there would be some suspicions that something was up. And so everybody
bought their tickets somewhere else, except me, because I figured if
everybody bought their tickets somewhere else...
So when I went to the train station and said, "I want to go to
Albuquerque, New Mexico," the man says, "Oh, so all this stuff is for you!"
We had been shipping out crates full of counters for weeks and expecting
that they didn't notice the address was Albuquerque. So at least I explained
why it was that we were shipping all those crates; I was going out to
Albuquerque.
Well, when we arrived, the houses and dormitories and things like that
were not ready. In fact, even the laboratories weren't quite ready. We were
pushing them by