“Surely You’re Joking, Mr. Feynman”: Adventures of a Curious Character

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 shortterm 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 he 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! ”