Theoretically a bullet fired straight up strikes the ground with the same speed at which it was fired--so the slugs would have been flattened anyway. But we had noticed a thin film of some substance unknown to us around the slugs which had been first fired into the wall. That same substance was clinging to the several slugs we managed to sift up from the sand. Our wall of invisible tension was a dome! "I feel like a bug!" said Preble. "I feel like a bug must feel when a scientist wants to study it. The scientist keeps covering it with a glass tumbler when it tries to walk or fly away!" "Do you suppose our own authorities," said Ziegler, "would be trying out a new interdiction weapon on us? Major, they wouldn't do it without at least telling you, sir, would they?" "They might," I said. "There are secret weapons only the highest high brass knows about. But if your hunch is right, corporal, we've sure got ourselves something, haven't we? Wouldn't it be something if we could throw an invisible net over every dive bomber of an enemy, every warship, every man, and nullify the attack before it got started?" "It would make them all feel pretty silly," said Preble. "But suppose an enemy had such a 'net'? Suppose it could reach out from anywhere in the world--" Slowly we all walked back to the LCVP's. "Something else funny," said Ziegler. "It's noon now, by our time. The sun says it's about four in the afternoon or thereabouts. But we're still ordinary marines, aren't we? Maybe I'm different from the rest of you, but doesn't it strike you as off--" "I'm not hungry," said Preble. "Nor thirsty! By this time of the day, when we had breakfast at oh-six-hundred at Guantanamo, I'd be starving." Preble was the company chow-hound. "But I'm not hungry, or thirsty. You, corporal?" Ziegler shook his head. He was by way of being a hearty eater himself, while I confess I came as close to being a glutton as an officer and a gentleman dares allow himself to be. We had hiked for several hours under a blazing sun. Moreover, all of us had sweated away a lot of moisture. Each of us carried a canteen of water, so water was not yet a problem; but the point is, none of us had taken a drink! When we got back to the LCVP's it was to find that nobody else was either hungry or thirsty.... "We're prisoners," said Captain Haggerty, "that's clear. And according to the laws of war, prisoners are fed. If we've been fed, and given water without eating or drinking, _how_?" "Through our pores!" said Preble impetuously. There was a long moment of silence which somebody had to break pretty soon. Lieutenant Hoose broke it. "Personally, I don't want to be sprinkled by something invisible, even if I'm dying of thirst. And if food is being somehow rubbed into us, I'd just as soon nobody rubbed it in! I'm not too lazy to chew for myself!"