Come to think of it – so had I!
It must have been the first time that Coertze had been in a boatyard and he looked about him with keen interest and asked a lot of questions, nearly all of them sensible. At last, he said, ‘Well, what about it?’
I took them down to the middle slip where Jimmy Murphy’s Estralita was waiting to be drawn up for an overhaul. ‘That’s a sailing yacht,’ I said. ‘A 15-tonner. What would you say her draft it – I mean, how deep is she in the water?’
Coertze looked her over and then looked up at the tall mast. ‘She’ll need to be deep to counterbalance that lot,’ he said. ‘But I don’t know how much. I don’t know anything about boats.’
Considering he didn’t know anything about boats, it was a very sensible answer.
‘Her draft is six feet in normal trim,’ I said. ‘She’s drawing less now because a lot of gear has been taken out of her.’
His eyes narrowed. ‘I’d have thought it would be more than that,’ he said. ‘What happens when the wind blows hard on the sails? Won’t she tip over?’
This was going well and Coertze was on the ball. I said, ‘I have a boat like this just being built, another 15-tonner. Come and have a look at her.’
I led the way up to the shed where Sanford was being built and Coertze followed, apparently content that I was leading up to a point. Walker tagged on behind.
I had pressed to get Sanford completed and she was ready for launching as soon as the glass-fibre sheathing was applied and the interior finished.
Coertze looked up at her. ‘They look bloody big out of the water,’ he commented.
I smiled. That was the usual lay reaction. ‘Come aboard,’ I said.
He was impressed by the spaciousness he found below and commented favourably on the way things were arranged. ‘Did you design all this?’ he asked.
I nodded.
‘You could live in here, all right,’ he said, inspecting the galley.
‘You could – and you will,’ I said. ‘This is the boat in which we’re going to take four tons of gold out of Italy.’
He looked surprised and then he frowned. ‘Where are you going to put it?’
I said, ‘Sit down and I’ll tell you something about sailing boats you don’t know.’ Coertze sat uncomfortably on the edge of the starboard settee which had no mattress as yet, and waited for me to explain myself.
‘This boat displaces – weighs, that is – ten tons, and …’
Walker broke in. ‘I thought you said she was a 15-tonner.’
‘That’s Thames measure – yacht measure. Her displacement is different.’
Coertze looked at Walker. ‘Shut up and let the man speak.’ He turned to me. ‘If the boat weighs ten tons and you add another four tons, she’ll be pretty near sinking, won’t she? And where are you going to put it? It can’t be out in the open where the cops can see it.’
I said patiently, ‘I said I’d tell you something about sailing boats that you didn’t know. Now, listen – about forty per cent of the weight of any sailing boat is ballast to keep her the right way up when the wind starts to press on those sails.’
I tapped the cabin sole with my foot. ‘Hanging on the bottom of this boat is a bloody great piece of lead weighing precisely four tons.’
Coertze looked at me incredulously, a dawning surmise in his eyes. I said, ‘Come on, I’ll show you.’
We went outside and I showed them the lead ballast keel. I said, ‘All this will be covered up next week because the boat will be sheathed to keep out the marine borers.’
Coertze was squatting on his heels looking at the keel. ‘This is it,’ he said slowly. ‘This is it. The gold will be hidden under water – built in as part of the boat.’ He began to laugh, and after a while Walker joined in. I began to laugh, too, and the walls of the shed resounded.
Coertze sobered suddenly. ‘What’s the melting point of lead?’ he asked abruptly.
I knew what was coming. ‘Four-fifty degrees centigrade,’ I said. ‘We’ve got a little foundry at the top of the yard where we pour the keels.’
‘Ja,’ he said heavily. ‘You can melt lead on a kitchen stove. But gold melts at over a thousand centigrade and we’ll need more than a kitchen stove for that. I know; melting gold is my job. Up at the smelting plant we’ve got bloody big furnaces.’
I said quickly, ‘I’ve thought of that one, too. Come up to the workshop – I’ll show you something else you’ve never seen before.’
In the workshop I opened a cupboard and said, ‘This gadget is brand new – just been invented.’ I hauled out the contraption and put it on the bench. Coertze looked at it uncomprehendingly.
There wasn’t much to see; just a metal box, eighteen inches by fifteen inches by nine inches, on the top of which was an asbestos mat and a Heath Robinson arrangement of clamps.
I said, ‘You’ve heard of instant coffee – this is instant heat.’ I began to get the machine ready for operation. ‘It needs cooling water at at least five pounds an inch pressure – that we get from an ordinary tap. It works on ordinary electric current, too, so you can set it up anywhere.’
I took the heart of the machine from a drawer. Again, it wasn’t much to look at; just a piece of black cloth, three inches by four. I said, ‘Some joker in the States discovered how to spin and weave threads of pure graphite, and someone else discovered this application.’
I lifted the handle on top of the machine, inserted the graphite mat, and clamped it tight. Then I took a bit of metal and gave it to Coertze.
He turned it in his fingers and said, ‘What is it?’
‘Just a piece of ordinary mild steel. But if this gadget can melt steel, it can melt gold. Right?’
He nodded and looked at the machine dubiously – it wasn’t very impressive.
I took the steel from his fingers and dropped it on to the graphite mat, then I gave Walker and Coertze a pair of welders’ goggles each. ‘Better put these on: it gets a bit bright.’
We donned the goggles and I switched on the machine. It was a spectacular display. The graphite mat flashed instantly to a white heat and the piece of steel glowed red, then yellow and finally white. It seemed to slump like a bit of melting wax and in less than fifteen seconds it had melted into a little pool. All this to the accompaniment of a violent shower of sparks as the metal reacted with the air.
I switched off the machine and removed my goggles. ‘We won’t have all these fireworks when we melt gold; it doesn’t oxidize as easily as iron.’
Coertze was staring at the machine. ‘How does it do that?’
‘Something like a carbon arc,’ I said. ‘You can get temperatures up to five thousand degrees centigrade. It’s only intended to be a laboratory instrument, but I reckon we can melt two pounds of gold at a time. With three of these gadgets and a hell of a lot of spare mats we should be able to work pretty fast.’
He said doubtfully, ‘If we can only pour a couple of pounds at a time, the keel is going to be so full of cracks and flaws that I’m not sure it won’t break under its own weight.’
‘I’ve thought of that one, too,’ I said calmly. ‘Have you ever watched anyone pour reinforced concrete?’
He