'Find somewhere lonely, fast,' Betty said. 'In less than three days. Then hide, hide, hide.'

The thunder of the mountains was majestic, terrifying.

Moira and Dan were on breakfast duty that morning. Dan had put up the trestle table in the middle of the laager, with the camp-chairs around it, and was laying out mugs, plates and cutlery. Moira, having brewed tea in the huge canteen pot Greg had picked up on one of his shopping sorties, was boiling eggs and toasting bread, at the canvas-screened cooker. She was thinking that before September was out they would have to devise a more sheltered kitchen area. Diana, beside her, was carefully unwrapping a half-kilo of butter, talking to it as she did so. Moira could hear

Rosemary singing in her tent as she got dressed and Greg teasing her. Angie and Eileen, in the open door of their caravan, were listening to the tail end of the seven o'clock radio news; it was Angle's news-monitoring day and Eileen always listened anyway – though since the Premier's announcement last night, she need not listen so anxiously. Thank heaven that worry's over, Moira thought; now all Britain knows about the vinegar masks… Then the first tremor came and she gasped dropping an egg – Diana had felt it, too, and asked 'Mummy?' anxiously. Moira snatched her up, instinctively moving away from the cooker. It was just as well she did because a second later there was another, worse tremor, which tumbled the boiling pan of water on to the ground where they had been standing.

Eileen called out: 'Respirators, everybody! Respirators!'

Moira ran to their tent, carrying Diana; Dan arrived a pace behind. Moira was saying hurriedly to Diana: 'Now, darling, this is the time we talked about. We'll all be all right but we all have to wear our respirators till Eileen says we can take them off…'

'I remember, Mummy. Because the air might make us sick.'

‘Very sick, darling. So we'll keep them on and be safe -right?'

Dan was soaking the vinegar-pads with quick, pre-measured amounts and securing them into the masks. They put Diana's on together and had just donned their own when the real quake came.

They clung together, gasping, for what seemed like many seconds while the earth shook beneath them, again and again, and the mountains roared in pain.

Then the shaking was over and the earth was still. But the thunder of the mountains went on, monstrous echoes flung back and forth' as though the Gods bellowed their anger. Diana was crying, the little sound strange and piteous in the rubber mask, while they hugged and rocked her.

At last, into the horizons of infinity, the echoes faded and died.

Cautiously, they stood up, and walked outside.

Nothing in the immediate neighbourhood seemed to have been damaged. The mountains, the trees, the cliff, the waterfall – all looked as they had before, even the tents still stood. Only a few things like the boiling saucepan, two of the camp-chairs and some crockery from the table, had been disrupted. On the meadow the five goats – a billy and four nannies – which New Dyfnant had presented to them tugged and called, careering round on the ends of their tethering-ropes. Of Ginger Lad there was no sign. Every bird in the forest was clamouring and flocks of them wheeled and zigzagged above the valley as if they no longer trusted the earth.

The radio had gone dead. With remarkable calmness -having assured herself that everyone was all right – Angie explored the tuning dial. Nothing on any British, Irish, or French wavelength, all of which she could normally pick up; a Spanish broadcast broke off even as she listened to it; and one German station was babbling away a stream of words which she did not understand but which sounded hysterical. Here and there the clicking whistle of Morse, otherwise nothing.

My God, Angie thought – it's big. Bloody big.

The seven of them gathered together, instinctively well out in the open. They had only just begun to talk, to get their breath back, when Peter's Land-Rover shot round the corner and across the grass to join them, with Peter at the wheel and Father Byrne beside him, both wearing their respirators.

'We're all right but there's damage further down,' Peter told them. 'A big landslide from the Moel Achles ridge -and there's a fissure right down one side of it, with the Dust pouring out. And the wind's this way. We'd better keep these things on till the air in the fissure's clear… Look, do you mind if I tow the trailer round later and we join your camp? I think we'd better be all together.'

They all agreed, of course. While they were talking about it, Peter suddenly cocked his head, listening. They all fell silent. Above the sound of the river they could pick out a deeper, more distant roar.

Rosemary said: 'Oh, please, no – not more earthquakes!'

Peter shook his head. 'No, not a steady noise like that… I'm afraid there's only one thing it can be. Billions of tonnes of water rushing down the Vyrnwy valley – and taking Llanwddyn with it. The dam must have gone.'

It had been a dreadful morning in New Dyfnant. About a quarter of the houses were uninhabitable and few of the rest had escaped some sort of damage; six people were dead, and twenty or thirty – Dr Owen had lost count -sufficiently injured to be incapacitated. The doctor had got around as best he could (a Y-shaped fissure had divided the village into three areas between which cars could not cross) and Dai Forest Inn had turned his saloon bar into a field hospital. Fortunately, everybody seemed to have got his vinegar mask on in time, the uninjured helping the injured, but the Dust had hit the village within minutes and only time would tell if anyone had breathed it. There was one grim exception: Tom Jenkins, an isolated smallholder who had been scornful of Eileen's warning until last night's official announcement and had run-white-faced to the village in search of vinegar twenty minutes after the earthquake struck. Bronwen had supplied him and had summoned Dai Police urgently. Dai had promptly locked Tom up; there seemed nothing else to do. He had promised Tom to send the doctor to him but Tom's terrified acquiescence had shown he had little faith in anything that could be done for him now.

Bronwen's shop, by some miracle, had suffered no more damage than broken windows. She had opened up immediately after the quake, pausing only to mask little Trevor and herself, and had served everybody who came whether or not they had money with them. She imposed her own hastily devised rationing system, having no idea when, or if, she would be able to re-stock. Some things, such as gas cylinders and kerosene, she refused to part with at all; the rationing of those might well have to be organized on a community basis. Jack Llewellyn, who ran the garage, was following a similar principle, allowing petrol only to the doctor, Dai Police, the minister and anyone else he decided was obliged to be mobile in the public interest. Electricity had failed immediately, of course, so Jack had to pump manually. He wondered if he would come to regret that his grandfather had changed the Llewellyns' hereditary craft from blacksmith to mechanic.

In all the frenzied activity, the vinegar masks were a great nuisance, hampering movement and producing sore mouths and noses after the first half-hour, but there was no alternative. The Dust was still visible till about ten o'clock, after which a quick reconnaissance showed no trace of it, either from the village fissures or from the bigger one on nearby Moel Achles. Remembering Eileen's two-hour safety margin, Dai Police extended it to two and a half, and passed the word round that the chapel bell would be rung as an all-clear when the masks could be put aside. The

Council had, years ago, installed a siren to give warning of forest fires, the village being surrounded by timber plantations on three sides; it had never had to be used but now it would serve as an alarm if the Dust reappeared.