“What would it say, though?”

“Some kind of warning, is my guess. You know, the way jet fighters say ‘Don’t stand here or you’ll get sucked into the engine’ in front of the air intake and ‘Keep away from the exhaust if you don’t want to get roasted’ at the tail.”

The older man smiled. “That makes a lot of sense. You are a science-fiction writer.”

“If I made a lot of sense all the time, I wouldn’t be able to write sf,” Jerry said. Steve laughed, for all the world as if he were joking. Jerry went on, “Can we get a message back to the mainland, to ask them to check it out themselves?”

“We can. It isn’t easy or convenient, but we can if it’s urgent enough.” Steve paused, then asked, “Do you know what a one-time pad is?”

“Sure do. Only shows I’ve read spy stories along with my sf when I should have been studying. You can agree on, for instance, two identical copies of the same book. The guy sending the message goes two one six, one two, four, and the guy getting it goes to page two sixteen, line twelve, word four and sees that it’s uranium. And so on.”

“Close enough. The way we do it here is, we spell message words out letter by letter inside the text of something that looks innocent. The person writing the message and the one deciphering it both know which letters count and which are just camouflage.”

Jerry thought about that for a moment. “Those innocent texts must be fun to put together. It’s like Scrabble—you can’t just drop in an X or a Q any old place.”

“You know who’s very good at it? Dave Schoals, the recovery director. He can write innocent-text poetry.”

“No shit?” Jerry said, impressed in spite of himself. Steve nodded. Jerry went on, “Boy, talk about a specialized skill!” That made the older man laugh. Jerry was not only impressed but surprised, though he didn’t say so to Steve. In spite of Dave’s longish hair and that god-awful mustache, Jerry would have guessed him too tightly wound to write any kind of poetry, let alone poetry with the constraints innocent text imposed.

“I’ll talk with him and with Dale. If they think finding out whether that’s writing is important enough, we’ll let people on the mainland know,” Steve said.

“Why wouldn’t they?” Jerry asked in surprise.

“Because even if it is writing, we can’t read it or do anything about it right now,” Steve answered. “And because the only way it will matter is if we can bring the spaceship up into the moon pool, and then we’ll be able to see for ourselves.”

“Oh.” Jerry felt foolish. He hated not thinking things through, but he could see he hadn’t this time. “Yeah. You’re right.”