Time had streamed by, hundreds of thousands of seasons, wet, dry, wet, dry, wet, dry, each wet softening the surface of the earth and each dry baking it hard again. Sometimes rain washed whole mountainsides away. Sometimes things barely changed at all.
‘I’ve seen sites which were explored thirty years before,’ said Dr Hamiska. ‘You could still see the old beer-cans. But not one new fossil had been exposed – barely a millimetre of erosion in thirty years. But then a man I know was digging out a dinosaur from the side of a gully. Tanzania, this was. A dinosaur can be a big thing – you don’t get it done in a day. He’d got it half done when there was a thunderstorm and a flash flood down the gully, and the whole dinosaur was washed away. He’d lost it completely.’
‘He must have been furious.’
‘Not at all. The flood had exposed an even better specimen below the first one. Now, look, that’s where we’re heading for.’
They had been steadily approaching the range of hills which millions of years before had been the coast of mainland Africa. From far off they’d seemed to rise sheer from the desolate flat plain, but now Vinny could see that there were foothills reaching out, brown and hummocky, below the ragged peaks. Dr Hamiska pointed towards a shapeless lump rising like a small island almost straight ahead, separate from the rest of the range.
‘Was it an island in the marsh?’ said Vinny.
‘It wasn’t anything. What seems to have happened was that there was a series of earthquakes which made those lower hills. They’re a real geological mess, but for some reason to do with the underlying rock-structure that outcrop was pushed up all of a piece, so that where the old strata are exposed they lie in the same order as that in which they were laid down. I’m not a professional geologist, but I know enough for my immediate purposes. If I can get a complete sequence of strata-deposition in this locality, then I may be able to match up partial sequences which I find elsewhere.’
‘Like tree-ring dating.’
‘Exactly. For instance, the skull May Anna is working on was found in association with a layer of tuff – that’s fossilized ash from a volcanic eruption. There are a whole series of tuffs in the strata, and I’m hoping that by sequencing the tuffs on this outcrop I can find out which is the one the skull belongs to, and hence get a line on the dating.’
‘Are there any fossils here?’
He laughed.
‘There were fossils here, Vinny. Some were brought to us from a point at the foot of the outcrop, eroded down the hill. Your father and a very experienced African did a survey, and they say there are no more to be found, but you and Jane and I are going to prove them wrong.’
He laughed again, but Vinny could hear it was only half a joke. Then he had to stop talking. They had been travelling so far along a sort of track, reasonably level, winding between the scrub and pits and hummocks of the plain. Now he left it, changed into low gear and edged down into what looked like a dry river-bed with soft, gritty sand in the bottom. There was no track at all on the other side. Still in low gear he took the jeep twisting and lurching along below the outcrop, so that Vinny had to clutch the back of the seats, though Mrs Hamiska sat calmly swaying, with her hands folded in her lap, as if on a church outing.
They stopped and climbed out, and now the heat of Africa smote them. Already, before they’d left the camp, Vinny had found it so hot that she’d been picking her way round through patches of shade rather than cross direct through the sunlit areas. The journey had been better with the breeze of movement blowing in under the jeep’s canvas roof. The badlands were hotter than she’d dreamed, even under the parasol, the green sun-brolly which Mrs Hamiska had lent her. (She’d thought she’d feel silly using it, but it made sense now.) Mrs Hamiska wore a sleeveless cotton frock and a straw hat, still looking as if she were on a church outing, while Dr Hamiska put on an old corduroy cap with its peak turned backwards to cover his neck. He should have looked a complete clown, but he didn’t.
‘The eroded finds were a couple of hundred yards along that way,’ he said. ‘We’ll have a look there later. But first I’d like you to come and help me measure the tuffs on that section of exposed rock. That’s where they’re clearest.’
He pointed up the slope to the left. The hill was a dark rusty brown with yellower patches, and here and there the dead-looking thorn-bushes. The odd boulder jutted out of the soil, but the only real difference was a section of low cliff two-thirds of the way up. He was starting to climb towards it when Mrs Hamiska bent and reached in under one of the thorn-bushes. Vinny hadn’t even noticed her looking. She rose with something in her hand.
‘Look at this, Joe,’ she said.
He turned and took the object from her, chuckling as he held it up between finger and thumb. From the ones she’d seen under the awning, Vinny recognized it as a fossil tooth.
‘Sam didn’t find everything, then,’ he said. ‘That’s about four million. Four point two. Somewhere round there.’
‘It makes my skin prickle, thinking about all that time,’ said Vinny.
‘And so it should. I tell my students that the past is an immense ocean which we can neither sail on nor dive down into. We are stuck to our shore, which is the present. Out on the surface we can see the past of the history books, the storms and the shipwrecks, but of what happened in the far past, down in the deeps of that ocean, we have nothing to go on except the shells and bones it chooses to wash up at our feet. Why do we bother, then? What does it matter? It matters because that ocean is where we come from. Those seas are in our blood.’
His voice throbbed. If he hadn’t told her, Vinny might still have guessed that this was part of a lecture.
‘I suppose you’ve got to be lucky to find the right things,’ she said.
‘Indeed you have. I know experts in my field who’ve never once had the excitement of picking up a hominid fossil. Others seem unable to step off an aeroplane without finding something new. That’s why I believe in luck. I seriously believe that there are some people who can call out across the ocean of time and summon it to wash its secrets to their feet. I am one, and for all I know you may be another.’
He gazed at the four-million-year-old fragment in his hand as if he were praying to it, using it for his summoning-magic, then gave it back to Mrs Hamiska.
‘See if you can spot where it came from, darling,’ he said. ‘Come on, Vinny.’
They started up the slope. It wasn’t much of a climb, but sweat streamed down Vinny’s body, making her clothes cling and pull, and she needed a rest half-way up. Looking back over the grey, roasting desert she tried to imagine it when it had been a marshy lake, steaming under this sun, with rivers running in and pigs rootling in the reed-beds, and other creatures, creatures who were almost people, perhaps, making their camp at the water’s edge . . . Mrs Hamiska was drifting along the slope half-way down, quiet as cloud-shadow, with her head bent like a nun in a cloister. Vinny climbed on and found Dr Hamiska measuring and sketching the slanting rock-layers in the cliff. He didn’t really need her to help him, only to be there so that he had someone to talk to, to teach.
‘You see this layering, how it’s tilted? This grey band? That’s tuff – remember? And here, just above it, these coarser particles, and then these finer ones and then this thin band of tuff again. So we had a minor volcanic eruption followed by a dry spell – not much flow in the rivers, you see – and then a wetter spell bringing heavier particles down from the hills, and then a really big eruption. That’s a very characteristic section. If it turns up elsewhere in the area I shall know where it comes in the sequence. Now I’m going to see if I can hack out some good unweathered crystals from the tuff. There’s a technique called potassium-argon dating . . .’