He must have known that the gas barrier was due to burst.
'Why didn't you ask him…?' I began.
The voice from the bunk, though weak, was resonant. 'Why don't you ask him yourself?'
Mary went over and took his arm from under the blanket. She crooked it in hers and at the same time drew me over, linking her free arm in mine. Caldwell tried to smile, but it turned into a grimace of pain and a fit of coughing. Mary wiped away the pinky foam.
I said awkwardly, 'We could have saved all this… The Mazy Zed offer…'
He replied, with a flash of his old self, 'You've got to get out of this bay quick, boy.'
'You'll be fine, once we get a doctor to you…'
He shook his head. 'It wasn't that I was thinking of… maybe I will, or maybe not. But there's a barrier of methane gas…'
'It's going to burst.'
'Yes,' he answered. 'I thought you must have worked it out, the way you set off inland. Yes, John, it's going to burst. I've waited a lifetime for it to happen. Once or twice it was pretty close, but it didn't come off, and the long wait began all over again. It's not a thing a man can do anything about. The old underground river floods when the rains are heavy on the mountains behind the desert. For it to be as it is now there must have been once-in-a-lifetime floods. When it breaks, it will sweep the diamonds out to sea — Oranjemund won't be in it…'
The Bells reverberated against the Gquma's hull.
'The whole bay is shaking like hell,' I said. 'Mercury is the centre…?'
'Yes,' he replied weakly. 'Mercury is the fountainhead of the Sperrgebiet.'
I couldn't forget the dead men. 'You tried to scare off the Mazy Zed rather than share it.'
Mary darted an angry glance at me, but Shelborne said, 'No, John, it wasn't that way. Strangely enough, I wanted to save lives. Yours, Rhennin's, those on the Mazy Zed. When the barrier goes, it will take everything with it — maybe Mercury too. Hundreds of thousands of tons of gravel and millions of gallons of water will be unleashed. In prehistoric times before the continent lifted, the flushing process was easy because the floods had freeway to the sea. If the Mazy Zed had been operating,' she would have been swept away like a twig in a maelstrom. So I used scare tactics, but they got out of hand — the Bells, the gas, the rest of it. Somehow in my life every good motive of mine has boomeranged and turned out wrong.' He smiled, but it was edged with bitterness. 'Caldwell's luck, you know. Mary has told you, of course?'
'Yes. What about the Praying Mantis?'.'
'I intended to wreck her and to rescue you all with the flatboom. I didn't bargain for a storm like that. I reckoned that once the survey vessel was out of the way, you'd stick to other places and not come back. I wasn't to know you were on to the fountainhead idea.'
'And the attack at Angras Juntas?'
He tried to shrug and his face went white with pain. Mary intervened, but he waved her aside. 'It wasn't the People's Second Atlantic Group, or whatever they call themselves, but a more private enterprise — a Polish fishing outfit based on Conakry, near Freetown. They run the occasional parcel of stones into West Africa for me, for a consideration, to keep my prospecting efforts going. They were only too pleased to have a crack at the opposition, but there again things misfired. They promised me they would do no more than inflict superficial damage and create enough rumpus to keep you away from Mercury. By the time you were able — or wanted — to get here I hoped the barrier would have exploded and the thing would have solved itself. But they took it as an opportunity to try to sink the Mazy Zed…'
'And Sookin Sin?' He hadn't heard about it. It was, we agreed, a clumsy attempt to try and shift the blame on to the Russian trawler fleets of the coast.
He was very weak, but I had to find out why he had helio-ed along the river march and where his water had come from.
'It wasn't a helio, John, but my water-maker. I learned it in the Takla Makan; it's a wooden-frame, covered with glass, with little gutters on the inside. You saw its reflection. In clean-blown sand like the Namib it is simple to find water, if you know how. Water will sink only a certain distance in dry sand. I've known places in the desert where some scanty rain has lain as a moist layer for years a couple of feet below the surface. Here on the coast with our heavy fog-dew the water lies close to the ground-level, but if you dug, all you'd get would be slight dampness. My sunbox draws it up, it condenses on the glass, and I tap off pure water via the little gutters. It gives, about a brandy bottle full a day — I lived like that for a year in completely waterless areas.'
He coughed and closed his eyes. Caldwell the legend had beaten the desert at its own game!
I didn't like the sound of his coughing. 'I'll get the sails on her,' I said.
'I'll help,' said Mary. There's not much I can do here.'
Shelborne had not exaggerated the handling qualities of the Gquma. The sun was low and the wind fresh from the south-west. We set all plain sail and she snored out of the bay with the starboard rail awash. At this rate, we'd make Walvis Bay in two days. Mary sat by me at the long-handled tiller for an hour or more until Mercury was out of sight behind the northern arm of the bay.
I turned to look at the wake to estimate our speed.
'Dear God!' exclaimed Mary.
The double doors of the coach-house in front of us flew open. Shelborne stood, a great crimson blotch across the white bandages.
His voice was strong, excited. 'John! Mary! Did you hear it!'
We exchanged glances. There had been no sound but the wind; we had left he Bells behind after clearing the bay.
He steadied himself on one of the bad-weather grab-handles, gazing hard out astern — towards Mercury. He cocked his head. 'It's come, John! It's come, Mary! Look! What a sight! The whole shoreline is being swept out to sea! There's never been a flood like it!' He lifted his hand and Mary stopped on her way to him. 'Listen! Hear that! — Mercury gone! Poor Mercury! — it was home to me for so long…' There was no sound except the creak of the boat and the thin whine of the wind in the rigging; the shore was invisible. 'The Mazy Zed will take diamonds for twenty miles out now, John! No need to worry about the methane problem any more.' He turned towards the tiller, but he didn't see me: his eyes were blind with agony. 'My special suit of sails — this is the occasion I made them for. Bring her round so that the wind is more aft, John… we'll get them up…'
His grip relaxed and he fell dead in the bottom of the boat.
It was five minutes before I could bring the Gquma to a halt. She lay pitching in the long swell. Mary knelt by him.
Then we heard it for the first time — the long shattering thunder of the break-through. Caldwell had waited a lifetime, but he lay lifeless before the sound could have reached us.
We stared at one another.
Mary said, 'He was given to hear it — before.'
We broke out the new suit of sails.