“What’s this?” “It’s a whale’s earbone,”said Bill, looking over his
shoulder.
“I’ve seem ’em before.” “Fight, Bill. Also made of sodium
triphosphate. We sometimes find them at the core of larger nodules but
more often it’s a shark’s tooth and most frequently a bit of clay.”
“So the manganese sticks to the tooth. How long does it take to make a
nodule?” Geordie asked.
“Estimates vary from one millimetre each thousand years to one
millimetre each million years. One chap estimated that it worked out
to one layerof atoms a day-which makes it one of the slowest chemical
reactions known. But I have my own ideas about that.” They both
stared at me. “Do you mean that if you find a nodule with a
half-diameter of ten millimetres formed round a tooth that the shark
lived ten million years ago? Were there sharks then?”Geordie asked in
fascination.
“Oh yes, the shark is one of our oldest inhabitants.” We talked a
little more and then I dropped it. They had a lot to learn yet and it
came best in small doses. And there was plenty of time for talk on
this voyage. We headed southsouth-west to cut through the Bahamas and
the approach to the Windward Passage. Once in the Passage we kept as
clear as possible of Cuba – once we came across an American destroyer
on patrol, which did us the courtesy of dipping her flag, to which we
reciprocated. Then there was the long leg across the Caribbean to
Colon and the entrance to the Panama Canal.
By then we had done our testing. There were minor problems, no more
than teething troubles, and generally I was happy with the way things
were going. Stopping to dredge a little, trying out the winch and
working out on-station routines, was an interesting change from what we
had been doing and everyone enjoyed it, and we remained lucky with the
weather. I got some nodules up but there was a lot of other material,
enough to cloud the issue for everyone but Geordie.
Among the debris of ooze, red clay and deposits we found enough shark’s
teeth and whale’s earbone to give everyone on board a handful of
souvenirs.
Both Geordie and Bill were becoming more and more interested in the
nodules and wanted to know more about them, so I arranged for another
lab. session with them one day. I’d been assaying, partly to keep my
hand in and partly to check on the readiness of my equipment for the
real thing.
“How did the Atlantic nodules turn out?” Geordie asked.
On the whole he did the talking – Bill watched, listened and
absorbed.
“Same old low quality stuff that’s always pulled out in the Atlantic,”
I said. “Low manganese, low iron and hardly anything else except
contaminants, clay and suchlike. That’s the trouble in the Atlantic;
there’s too much sediment even on the Blake Plateau.” “Why does
manganese behave this way – why does it lump together?” I laughed.
“You want me to give you a course of physical chemistry right now?
All right, I’ll explain it as simply as I can.
Do you know what a colloid is?” Two headshakes.
“Look. If you put a teaspoon of sugar into water you get a sugar
solution – that is, the sugar breaks down right to the molecular level
and mixes intimately with the water. In other words, it dissolves.
Right?” “Right.” “Now what if you have a substance that won’t
dissolve in water but is divided into very fine particles, much smaller
than can be seen in a regular microscope, and each particle is floating
in the water? That’s a colloid. I could whip you up a colloid which
looks like a clear liquid, but it would be full of very small
particles.” “I see the difference,” Geordie said.
“All right. Now, for reasons that I won’t go into now an colloidal
particles must carry an electric charge. iiese charges make the
colloidal particles of manganese dioxide clump together in larger and
larger units. They also tend to be attracted to any electrically
conductive surfaces such as a shark’s tooth or a bit of clay. Hence
the nodules.” “You mean,” said Bill slowly, ‘that having broken down a
long time before, the manganese is trying to get together again.
“Pretty well just that, yes.” “Where does the manganese come from in
the first place when it starts clumping, that is?” “From the rivers,
from underground volcanic fissures, from the rocks of the sea bottom.
Fellows, the sea out there is a big chemical broth. In certain
localized conditions the sea becomes alkaline and the manganese in the
rocks leaches out and dissolves in the water. . .
“You said it doesn’t dissolve.” “Pure metallic manganese will dissolve
as long as the conditions are right, and that’s what chemists call a
“reducing atmosphere”. Just believe me, Geordie. Currents carry the
dissolved manganese into “oxidising atmospheres” where the water is
more acid. The manganese combines with oxygen to form manganese
dioxide which is insoluble and so forms a colloid – and then the
process goes on as I’ve described.” He thought about that. “What
about the copper and nickel and cobalt and stuff that’s in the
nodules?” “How does the milk get into the coconut?” We all laughed,
taking some of the schoolroom air out of the lab. “Well, all these
metals have certain affinities for each other. If you look at the
table of elements you’ll find they’re grouped closely together by
weight – from manganese, number twenty-five, to copper, number
twenty-nine. What happens is that as the colloidal particles grow
bigger they scavenge the other metals – entrap them. Of course, this
is happening over a pretty long period of time.”
“Say a hundred million years or so,”said Geordie ironically.
“Ah well, that’s the orthodox view.” “You think it can happen faster
than that?” “I think it could happen fast,”I said slowly. “Given the
right conditions, though just what these conditions would be I’m not
sure. Someone else doing research thought so too, though I haven’t
been able to follow his reasoning. And I have seen pecularities that
indicate rapid growth. Anyway that’s one of the objects of this trip
to find out.” What I didn’t say in Bill’s hearing was that the
‘somebody’ was Mark, nor that the peculiarities I had seen were
contained in the prize nodule left from his collection.
And there was something else I didn’t talk about; the peculiarities
that led to high-cobalt assay. I was beginning to grope towards a
theory of nodule formation which, though still vague, might ease the
way ahead. I was becoming anxious to know how Campbell’s cipher expert
had made out in translating Mark’s diary.
Ten days after leaving the Blake Plateau we warped into the dockside at
Panama. At last we were in the Pacific, all my goals a step nearer.
Campbell was waiting for us, jumped spryly aboard and shook hands with
me and Geordie, waving genially at the rest of the crew.
“You made a good fast trip,”he said.
“Not so bad,”said Geordie complacently.
Campbell looked about the Esmerelda and at the crew who were busy
stowing sail and clearing the decks. “So this is your crew of
cut-throats and desperadoes,” he said. He was in a jocular mood- a
mercurial man.”I hope we won’t need them.” He took my arm and walked
me along the dock, amused at my wobbling land-legs.
“I’ve booked you into my hotel for a night or so; there’s no reason why
you shouldn’t have a last taste of luxury before the big job. Geordie
too, if he wants it. I’ll expect you both to dinner you can’t miss the
hotel, it’s the Colombo, right on the main street.
You can tell me all about the trip then.
Meantime I want to talk to you in private, now.” He steered me into
one of the waterfront bars that always seem to be handy, and I sat down
thankfully in front of a large glass of cold beer.
Campbell wasted no time. He produced a biggish envelope from his
jacket. “I had photostats made of the diary pages,” he said. “The
original’s in a bank vault in Montreal. You don’t mind? You’ll get it
back one day.” “Not at all,” I said.
He shook out the contents of the envelope. “I got the translation
done. My guy said it was a bastard of a job – he only hopes he’s got
the scientific bits right.” “We’ll soon find out.” I was stiff with
eagerness.
Campbell handed me a neatly bound booklet which I flicked through.
“That’s the stat of the original diary. This one’s the translation.
There are reproductions of all the drawings at the back. The whole
thing looks screwy to me – it had better make sense to you or this
whole thing is a bust already.” His good humour had already
evaporated, but I was getting used to his changes of mood.