“Do you drink?”

“Some.” He was feeling distinctly defensive. No question about it.

“May I ask when you last consumed an alcoholic beverage, sir?”

“I don’t know. Two, three days ago.” He was having trouble thinking back to San Diego. It seemed so far away. “Why?”

“That’s fine, Dr. Johnson. Any trouble with joints, hips or knees?”

“No, why?”

“Episodes of syncope, faintness or blackouts?”

“No…”

“If you would just sit over here, sir.” The corpsman pointed to a stool, next to an electronic device on the wall. “I’d really like some answers,” Norman said.

“Just stare at the green dot, both eyes wide open…”

He felt a brief blast of air on both eyes, and blinked instinctively. A printed strip of paper clicked out. The corpsman tore it off, glanced at it.

“That’s fine, Dr. Johnson. If you would come this way…” “I’d like some information from you,” Norman said. “I’d like to know what’s going on.”

“I understand, sir, but I have to finish your workup in time for your next briefing at seventeen hundred hours.”

Norman lay on his back, and technicians stuck needles in both arms, and another in his leg at the groin. He yelled in sudden pain.

“That’s the worst of it, sir,” the corpsman said, packing the syringes in ice. “If you will just press this cotton against it, here…”

There was a clip over his nostrils, a mouthpiece between his teeth.

“This is to measure your CO₂” the corpsman said. “Just exhale. That’s right. Big breath, now exhale…”

Norman exhaled. He watched a rubber diaphragm inflate, pushing a needle up a scale.

“Try it again, sir. I’m sure you can do better than that.” Norman didn’t think he could, but he tried again anyway. Another corpsman entered the room, with a sheet of paper covered with figures. “Here are his BC’s,” he said.

The first corpsman frowned. “Has Barnes seen this?”

“Yes.”

“And what’d he say?”

“He said it was okay. He said to continue.”

“Okay, fine. He’s the boss.” The first corpsman turned back to Norman. “Let’s try one more big breath, Dr. Johnson, if you would…”

Metal calipers touched his chin and his forehead. A tape went around his head. Now the calipers measured from his ear to his chin.

“What’s this for?” Norman said.

“Fitting you with a helmet, sir.”

“Shouldn’t I be trying one on?”

“This is the way we do it, sir.”

Dinner was macaroni and cheese, burned underneath. Norman pushed it aside after a few bites.

The corpsman appeared at his door. “Time for the seventeen-hundred-hours briefing, sir.”

“I’m not going anywhere,” Norman said, “until I get some answers. What the hell is all this you’re doing to me?”

“Routine deepsat workup, sir. Navy regs require it before you go down.”

“And why am I off the graph?”

“Sorry, sir?”

“You said I was off the graph.”

“Oh, that. You’re a bit heavier than the Navy tables figure for, sir.”

“Is there a problem about my weight?”

“Shouldn’t be, no, sir.”

“And the other tests, what did they show?”

“Sir, you are in very good health for your age and lifestyle.”

“And what about going down there?” Norman asked, half hoping he wouldn’t be able to go.

“Down there? I’ve talked with Captain Barnes. Shouldn’t be any problem at all, sir. If you’ll just come this way to the briefing, sir…”

The others were sitting around in the briefing room, with Styrofoam cups of coffee. Norman felt glad to see them. He dropped into a chair next to Harry. “Jesus, did you have the damn physical?”

“Yeah,” he said. “Had it yesterday.”

“They stuck me in the leg with this long needle,” Norman said.

“Really? They didn’t do that to me.”

“And how about breathing with that clip on your nose?”

“I didn’t do that, either,” Harry said. “Sounds like you got some special treatment, Norman.”

Norman was thinking the same thing, and he didn’t like the implications. He felt suddenly tired.

“All right, men, we’ve got a lot to cover and just three hours to do it,” a brisk man said, turning off the lights as he came into the room. Norman hadn’t even gotten a good look at him. Now it was just a voice in the dark. “As you know, Dalton’s law governs partial pressures of mixed gases, or, as represented here in algebraic form…”

The first of the graphs flashed up.

PP_a = P_tot x % Vol_a

“Now let’s review how calculation of the partial pressure might be done in atmospheres absolute, which is the most common procedure we employ-”

The words were meaningless to Norman. He tried to pay attention, but as the graphs continued and the voice droned on, his eyes grew heavier and he fell asleep.

“-be taken down in the submarine and once in the habitat module you will be pressurized to thirty-three atmospheres. At that time you will be switched over to mixed gases, since it is not possible to breathe Earth atmosphere beyond eighteen atmospheres-”

Norman stopped listening. These technical details only filled him with dread. He went back to sleep, awakening only intermittently.

“-since oxygen toxicity only occurs when the PO₂ exceeds point 7 ATA for prolonged periods-

“-nitrogen narcosis, in which nitrogen behaves like an anesthetic, will occur in mixed-gas atmospheres if partial pressures exceeds 1.5 ATA in the DDS-

“-demand open circuit is generally preferable, but you will be using semiclosed circuit with inspired fluctuations of 608 to 760 millimeters-”

He went back to sleep.

When it was over, they walked back to their rooms. “Did I miss anything?” Norman said.

“Not really.” Harry shrugged. “Just a lot of physics.”

In his tiny gray room, Norman got into bed. The glowing wall clock said 2300. It took him a while to figure out that that was 11:00 p.m. In nine more hours, he thought, I will begin the descent.

Then he slept.

In the morning light, the submarine Charon V bobbed on the surface, riding on a pontoon platform. Bright yellow, it looked like a child’s bathtub toy sitting on a deck of oildrums.

A rubber Zodiac launch took Norman over, and he climbed onto the platform, shook hands with the pilot, who could not have been more than eighteen, younger than his son, Tim.

“Ready to go, sir?” the pilot said.

“Sure,” Norman said. He was as ready as he would ever be.

Up close, the sub did not look like a toy. It was incredibly massive and strong. Norman saw a single porthole of curved acrylic. It was held in place by bolts as big as his fist. He touched them, tentatively.

The pilot smiled. “Want to kick the tires, sir?”

“No, I’ll trust you.”

“Ladder’s this way, sir.”

Norman climbed the narrow rungs to the top of the sub, and saw the small circular hatch opening. He hesitated.

“Sit on the edge here,” the pilot said, “and drop your legs in, then follow it down. You may have to squeeze your shoulders together a bit and suck in your… That’s it, sir.” Norman wriggled through the tight hatch into an interior so low he could not stand. The sub was crammed with dials and machinery. Ted was already aboard, hunched in the back, grinning like a kid. “Isn’t this fantastic?”

Norman envied his easy enthusiasm; he felt cramped and a little nervous. Above him, the pilot clanged the heavy hatch shut and dropped down to take the controls. “Everybody okay?”

They nodded.

“Sorry about the view,” the pilot said, glancing over his shoulders. “You gentlemen are mostly going to be seeing my hindquarters. Let’s get started. Mozart okay?” He pressed a tape deck and smiled. “We’ve got thirteen minutes’ descent to the bottom; music makes it a little easier. If you don’t like Mozart, we can offer you something else.”