But at the time the boat was swinging, Captain Cormack wasn't around for me to watch his expression. The boat was going whoooomp, water crashing against the portholes, and, to put it mildly, I just about freaked out.

Other crew members, Lyle Thurston, Bill Darnell, Pat Moore, Bob Kienkeziere and Bob Cummings, have all conceded that they went through the same bad trip.

Up to this point, I had been going along thinking that I wasn't scared and that none of the others was either. It's called the Jock Game. We like to think of ourselves as Greenhawks, but the truth is we are also Greenchickens.

In a way, I'm glad to know it. If we weren't scared, we'd be crazy. We are trying to keep it all very easygoing, making like it's really a kind of picnic, and that's just good psychology. High morale makes for better performance and all that.

But the truth is, we are likely to run into some bad weather. Which means weather that is potentially harmful to human life. Ships do sink.

And on top of that, despite the manoeuvring of the Atomic Energy Commission, the odds are that the bomb will be set off. I suspect that the American military megamachine has too much momentum to be stopped so easily. Which means we face the possibility of a shock wave and finally radiation.

We have worked out a vague arrangement to deal with that situation, should it develop. The crewmen who are already fathers - Bohlen, Metcalfe and me - will go out on deck after the fallout cloud passes, assuming the test does leak, dressed in slicks, and attempt to wash off the decks and walls.

The guys who haven't had any kids yet will stay below, in the hope that the dose of radiation they get won't be quite so lethal to their genes.

There are moments, not surprisingly, when I wonder whether we all aren't crazy.

That's why I was pleased to notice that we are all basically scared. The flicker of fear that registered in all our faces is the only proof I have that we are quite sane.