I could feel the heat hovering outside. In the cabin it was bright and dry and cool, almost too cool, like a modern office building in the dead of the summer. Beyond the two small windows it was as black as it ever gets in the solar system, and hot enough to melt lead, at a pressure equivalent to three hundred feet beneath the ocean.

"There goes a fish," I said, just to break the monotony.

"So how's it cooked?"

"Can't tell. It seems to be leaving a trail of breadcrumbs.

"Fried? Imagine that, Eric! A fried jellyfish."

Eric sighed noisily. "Do I have to?"

"You have to. Only way you'll see anything worthwhile in this..this.." Soup? Fog? Boiling maple syrup?

"Searing black calm."

"Right."

"Someone dreamed up that phrase when I was a kid, just after the news of the Mariner II probe. An eternal searing black calm, hot as a kiln, under an atmosphere thick enough to keep any light or any breath of wind from ever reaching the surface."

I shivered. "What's the outside temperature now?"

"You'd rather not know. You've always had too much imagination, Howie."

"I can take it, Doc."

"Six hundred and twelve degrees."

"I can't take it, Doc!"

This was Venus, Planet of Love, favorite of the science-fiction writers of three decades ago. Our ship hung below the Earth- to-Venus hydrogen fuel tank, twenty miles up and all but motionless in the syrupy air. The tank, nearly empty now, made an excellent blimp. It would keep us aloft as long as the internal pressure matched the external. That was Eric's job, to regulate the tank's pressure by regulating the temperature of the hydrogen gas. We had collected air samples after each ten mile drop from three hundred miles on down, and temperature readings for shorter intervals, and we had dropped the small probe. The data we had gotten from the surface merely confirmed in detail our previous knowledge of the hottest world in the solar system.

"Temperature just went up to six-thirteen," said Eric. "Look, are you through hitching?"

"For the moment."

"Good. Strap down. We're taking off."

"Oh fabulous day!" I started untangling the crash webbing over my couch.

"We've done everything we came to do. Haven't we?"

"Am I arguing? Look, I'm strapped down."

"Yeah."

I knew why he was reluctant to leave. I felt a touch of it myself. We'd spent four months getting to Venus in order to spend a week circling her and less than two days in her upper atmosphere, and it seemed a terrible waste of time.

But he was taking too long. "What's the trouble, Eric?"

"You'd rather not know."

He meant it. His voice was a mechanical, inhuman monotone; he wasn't making the extra effort to get human expression out of his "prosthetic" vocal apparatus. Only a severe shock would affect him that way.

"I can take it," I said.

"Okay. I can't feel anything in the ramjet controls. Feels like I've just had a spinal anaesthetic."

The cold in the cabin drained into me, all of it. "See if you can send motor impulses the other way. You could run the rams by guess-and-hope even if you can't feel them."

"Okay." One split second later, "They don't. Nothing happens. Good thinking though."

I tried to think of something to say while I untied myself from the couch. What came out was, "It's been a pleasure knowing you, Eric. I've liked being half of this team, and I still do."

"Get maudlin later. Right now, start checking my attachments.

Carefully."

I swallowed my comments and went to open the access door in the cabin's forward wall. The floor swayed ever so gently beneath my feet.

Beyond the four-foot-square access door was Eric. Eric's central nervous system, with the brain perched at the top and the spinal cord coiled in a loose spiral to fit more compactly into the transparent glass-and-sponge-plastic housing. Hundreds of wires from all over the ship led to the glass walls, where they were joined to selected nerves which spread like an electrical network from the central coil of nervous tissue and fatty protective membrane.

Space leaves no cripples; and don't call Eric a cripple, because he doesn't like it. In a way he's the ideal spaceman. His life support system weighs only half of what mine does, and takes up a twelfth as much room. But his other prosthetic aids take up most of the ship. The ramjets were hooked into the last pair of nerve trunks, the nerves which once moved his legs, and dozens of finer nerves in those trunks sensed and regulated fuel feed, ram temperature, differential acceleration, intake aperture dilation, and spark pulse.

These connections were intact. I checked them four different ways without finding the slightest reason why they shouldn't be working.

"Test the others," said Eric.

It took a good two hours to check every trunk nerve connection. They were all solid. The blood pump was chugging along, and the fluid was rich enough, which killed the idea that the ram nerves might have "gone to sleep" from lack of nutrients or oxygen. Since the lab is one of his prosthetic aids, I let Eric analyse his own blood sugar, hoping that the "liver" had goofed and was producing some other form of sugar. The conclusions were appalling. There was nothing wrong with Eric inside the cabin.

"Eric, you're healthier than I am."

"I could tell. You looked worried, son, and I don't blame you.

Now you'll have to go outside."

"I know. Let's dig out the suit."

It was in the emergency tools locker, the Venus suit that was never supposed to be used. NASA had designed it for use at Venusian ground level. Then they had refused to okay the ship below twenty miles until they knew more about the planet. The suit was a segmented armor job. I had watched it being tested in the heat-and-pressure box at Cal Tech, and I knew that the joints stopped moving after five hours, and wouldn't start again until they had been cooled. Now I opened the locker and pulled the suit out by the shoulders and held it in front of me. It seemed to be staring back.

"You still can't feel anything in the ramjets?"

"Not a twinge."

I started to put on the suit, piece by piece like medieval armor. Then I thought of something else. "We're twenty miles up. Are you going to ask me to do a balancing act on the hull?"

"No! Wouldn't think of it. We'll just have to go down."

The lift from the blimp tank was supposed to be constant until takeoff. When the time came Eric could get extra lift by heating the hydrogen to 'higher pressure, then cracking a valve to let the excess out. Of course he'd have to be very careful that the pressure was higher in the tank, or we'd get Venusian air coming in, and the ship would fall instead of rising. Naturally that would be disastrous.

So Eric lowered the tank temperature and cracked the valve, and down we went.

"Of course there's a catch," said Eric.

"I know."

"The ship stood the pressure twenty miles up. At ground level it'll be six times that."

"I know."

We fell fast, with the cabin tilted forward by the drag on our tailfins. The temperature rose gradually. The pressure went up fast. I sat at the window and saw nothing, nothing but black, but I sat there anyway and waited for the window to crack- NASA had refused to okay the ship below twenty miles : . .

Eric said, "The blimp tank's okay, and so's the ship, I think.

But will the cabin stand up to it?"

"I wouldn't know."

"Ten miles."

Five hundred miles above us, unreachable, was the atomic ion engine that was to take us home. We couldn't get to it on the chemical rocket alone. The rocket was for use after the air became too thin for the ramjets.