The Vivero Letter

She reached for it mechanically, and I turned my attention to the cave. It was fairly big and I judged the volume to be in excess of three thousand cubic feet -- we'd had to pump a hell of a lot of air into it from the surface to expel the water. At that depth the air was compressed to three atmospheres, therefore it contained three times as much oxygen as an equal volume at the surface, which was a help. But with every breath we were exhaling carbon dioxide and as the level of CO2 built up so we would get into trouble.

I rested for a while and watched the light reflect yellowly from the pile of gold plate at the further end of the ledge. The problem was simple; the solution less so. The longer we stayed down, the longer we would have to decompress on the way up -- but the bottles in the back-packs didn't hold enough air for lengthy decompression. At last I bent down and swished my mask in the water before putting it on.

Katherine sat up. 'Where are you going?'

'I won't be long,' I said. 'Just to the bottom of the cenote to find a way of stretching our stay here. You'll be all right -- just relax and take things easy.'

'Can I help?'

I debated that one, then said, 'No, You'll just use up air.

There's enough in the cave to keep us going, and I might need what you have in that bottle.'

She looked up at the light and shivered. 'I hope that doesn't go out. It's strange that it still works.'

The batteries topside are still full of juice,' I said. 'That's not so strange. Keep cheerful -- I wont be long.'

I donned my mask, slipped into the water and swam out of the cave, and then made for the bottom. I found one of our working lights and debated whether or not to switch it on because it could be seen from the surface. In the end I risked it -- there wasn't anything Gatt could do to get at me short of inventing a depth charge to blow me up, and I didn't think he could do that at short notice.

I was looking for the air cylinders Rudetsky and I had pushed off the raft and I found them spread out to hell and gone. Finding the manifold that had followed the cylinders was a bit more tricky but I discovered it under the coils of air hose that spread like a huge snake, and I smiled with satisfaction as I saw the spanner still tied to it by a loop of rope. Without that spanner I'd have been totally sunk.

Heaving the 'cylinders into one place was a labour fit for Hercules but I managed it at last and set about coupling up the manifold. Divers have very much the same problem of weightlessness as astronauts, and every time I tried to tighten a nut my body rotated around the cylinder in the other direction. I was down there nearly an hour but finally I got the cylinders attached to the manifold with all cocks open, and the hose on to the manifold outlet with the end valve closed. Now all the air in the cylinders was available on demand at the end of the hose.

I swam up to the cave, pulling the hose behind me, and popped up beside the ledge holding it triumphantly aloft. Katherine was sitting at the further end of the ledge, and when I said. 'Grab this!' she didn't do a damn thing but merely turned and looked at me.

I hoisted myself out of the water, holding the end of the hose with difficulty, and then hauled in a good length of it and anchored it by sitting on it. 'What's the matter with you?' I demanded.

She made no answer for some time, then said cheerlessly, 'I've been thinking about Fallon.'

'Oh!'

'Is that all you can say?' she asked with passion in her voice, but the sudden violence left her as soon as it had come. 'Do you think he's dead?' she asked more calmly.

I considered it. 'Probably,' I said at last.

'My God, I've misjudged you,' she said in a flat voice. 'You're a cold man, really. You've just left a man to die and you don't care a damn.'

'What I feel is my business. It was Fallen's decision -- he made it himself.'

'But you took advantage of it.'

'So did you,' I pointed out.

'I know,' she said desolately. 'I know. But I'm not a man; I can't kill and fight.'

'I wasn't brought up to it myself,' I said acidly. 'Not like Gatt. But you'd kill if you had to, Katherine. Just like the rest of us. You're a human being -- a killer by definition. We can all kill, but some of us have to be forced to it.'

'And you didn't feel you had to defend Fallon,' she said quietly.

'No, I didn't,' I said equally quietly. 'Because I'd be defending a dead man. Fallon knew that, Katie; he's dying of cancer. He's known it ever since Mexico City, which is why he's been so bloody irresponsible. And now it's on his conscience. He wanted to make his peace, Katie; he wanted to purge his conscience. Do you think I should have denied him that -- even though we're ail going to die anyway?'

I could hardly hear her. 'Oh, God!' she breathed. 'I didn't know -- I didn't know.'