As I said, it was about the size and weight of a bowling ball. Now, I was so ignorant; I sort of knew it was plutonium. I think I knew, maybe I didn't know but it was something like that. I was so ignorant that I did not ask the obvious question, which was why was it so light. A solid sphere, like a bowling ball of plutonium, would have weighed hundreds of pounds and I couldn't possibly have lifted it, but I could lift it and hold it in my hand. So the obvious question was, why was it so light? And if I had asked that question, I either would have been thrown out or certainly not given an answer. The answer was obviously that it was hollow, it was a hollow sphere of plutonium, and the next question was, why was it hollow? Well, it was hollow because they were testing one of those boosted weapons, which light hydrogen isotypes and the like are inserted in one form or another in the interior of the weapons, and when the pit is imploded and the fission begins then fusion is induced.

So you have… it's a mixture of a fission and a boosted device, in which there is fusion. It's not a proper hydrogen bomb, but it uses the same principle. And then this fusion produces a blast of energetic neutrons, which enhances the fission. So... it's a fusion-boosted device. That's what was being tested. Of course, I would not have been told that, I would have probably been sent away, but I didn't ask the question because I didn't know that was the question to ask.