'There's a noise ahead,' Philip told him. 'Sounds like a crowd arguing.'

'Hell. The last thing we want.'

They rounded the right bend in Lower Street and saw it.

'My God! Troops! First we've run into.'

'Troops' was perhaps an exaggeration. A young lieutenant, a lance-corporal, and four privates were strung out in front of the smashed windows of a big supermarket. The officer had a revolver in his holster and the five soldiers carried their rifles at the port. The crowd of men and women who faced them looked angry and resentful. One of the men was arguing with the officer. As Harry and his group came up behind the crowd, the young officer raised his voice.

'Look, everybody – go home. Until I get new orders, my job's to prevent looting. And that's what I'm going to do. So clear this crowd.'

'Orders from where, sonny?' somebody called, mockingly. 'There's no one to give 'em.'

The officer flushed. 'Don't you count on that. Anyhow, that's my business. Go home.'

'Stupid puppy,' Harry muttered to Philip.

There was a chorus of 'What homes?' and another cry from the mocking voice. 'Stop looting, eh? Six of you? There's dozens of shops, sonny.'

'This is the biggest and it's where the food is. So we'll go on protecting it.'

A woman pushed forward out of the crowd towards him, shouting furiously: 'Too right it's where the food is! And we've got hungry kids! What the hell d'you think you're trying to do? You and your "orders"! Get out of our way!'

She was almost on him and he drew his revolver, taking a hasty step backwards. The crowd sensed his nervousness and at the same time were angered by his threat to the woman. They moved closer.

Harry said, 'Jesus, he's asking for it.'

A moment of poised silence was broken by noises from inside the supermarket. The lance-corporal said, 'They've got in the back way, sir.'

'Hendry – Powers – through the shop! Stop 'em!'

The soldiers never had a chance to obey. As the officer shouted his order, the crowd rushed forward. Two shots rang out and that was all; the crowd was instantly an enraged mob, overwhelming the khaki figures, milling around them for a few seconds and then pouring into the shop.

It was all over before Harry and his group had caught their breath.

They stared down at the six soldiers; the officer was certainly dead, the rest either dead or stunned. The woman who had challenged the officer lay at his side with a bullet through her chest, and another civilian was staggering into the shop after the crowd clutching a bleeding arm.

'Come on!' Harry cried. 'It's done. Might as well get our share.'

They began to run. Philip shouted to Harry: 'The guns! Get the guns!' 'Christ, yes!'

It took them half a minute, at most, to strip the soldiers of their arms and ammunition. Harry ordered one of his men back to the car with them and the remaining four hurried into the supermarket.

Inside was chaos; displays tumbling as people grabbed at tins and boxes, bottles smashing as they stumbled into each other. Strangely, few had thought of taking a trolley – perhaps fearing it would hamper them. There were still four left and Harry's group seized them, trying to keep calm and work methodically, choosing the most compact goods, remembering small unnoticed valuables such as yeast and sticking plasters and salt and a card of throw-away lighters, trying an unopened door which might, and did, hide more meat (the meat counter had been stripped in seconds), and paying a flying visit to the hardware shelves, where Philip found a treasure they lacked – a camping-gas ring with spare cylinders.

Harry was a natural commander. He managed to keep an eye on all his group, coordinate their efforts without fuss, avoid clashes and order withdrawal at just the right moment.

They must have been a bizarre sight, four grown men careering through Kettering with loaded supermarket trolleys like women in a perambulator race. But nobody stopped them and they reached the car with all their loot. The man who had carried the guns ahead was very relieved to sec them. He was standing guard over the car with the revolver, while a group of young men across the road eyed him speculatively.

They drove back to the wood without incident and were welcomed as returning heroes. But the women had not been idle. Tonia proudly produced a plastic pail of still-warm, frothy milk.

'Found a cow,' she announced. 'Poor old girl was in the hell of a state. Well, we've all got to help each other with our problems, these days – haven't we?'

They never did solve the puzzle of the abandoned farm. It was about a kilometre from the wood and they were led to it by another cow's distressed mooing – Tonia's friend's companion was obviously confined there and equally obviously unattended. Harry and Philip, with Tonia as the nearest they had to an agricultural expert, went to investigate. Tonia's opinion, after administering emergency relief to the cow and examining such tell-tale evidence as the hencoops and the kitchen, was that the farm had been empty of humans for at least two days. Beds and clothing suggested that a couple and a young man, perhaps their son, had lived there. Maybe they had been in one of the market towns when the earthquake struck and been killed. Maybe they had taken fright at their isolation and fled to relatives. Whatever the explanation, they had plainly gone, and all the signs were that they would not be back.

The three of them returned to the wood and called a conference, at which Philip told the others the truth about the effect of the Dust, and the coming need for the utmost in self-defence. The debate was not long. Within an hour, they had packed their cars and moved to the farm – six men, five women, two girls aged fourteen and eleven, and a seven-year-old boy.

It was plain from its equipment and the bills and receipts that littered an old roll-top desk that the farm had not commanded many hectares. But the building itself was old and rambling, probably a relic of more prosperous days, and it had bedrooms enough for all of them if the three single men used the loft as a dormitory. It was also virtually undamaged; four broken windows and a fractured pantry wall.

They had two milch cows, a somewhat elderly horse, three young pigs, some poultry, a questionably adequate stock of hay and other feed, plenty of potatoes and vegetables and a water-pump that worked. They also had enough adults for round-the-clock sentries, five rifles, a shotgun, a revolver and some, if not much, ammunition.

Given luck, they reckoned that they could manage.

Fewer of the Vyrnwy river valley people had survived than their neighbours in New Dyfnant had hoped, and most of the scattered handfuls that did fell to the madmen.

In the first minutes after the earthquake, the majority had managed to reach the vinegar masks they had prepared. But house damage had been greater than in New Dyfnant. Many had been trapped or crushed; vinegar and gauze carefully kept ready had often been buried in wreckage; the untrapped desperately trying to free the trapped had often forgotten about their masks till it was too late. And almost at once, into the middle of this chaos, had swept the great wall of water from the burst dam.

How the few refugees from the flood who had been able to reach higher ground on the other side of the valley had fared, New Dyfnant did not know as yet. But thirty or forty of them from the near side had reached the village and been taken in by families with relatively undamaged homes or housed temporarily in the village hall. All but three of them had arrived holding vinegar masks to their faces and claimed to have been using them from the start. The three without masks had been locked up with Tom Jenkins – two of -them were too numb with shock to protest. The third resisted so violently that Dai Police had had to handcuff him till he cooled down, which had taken half an hour while Dai talked to him, using up time the constable could ill spare.