They walked on and presently, through the soles of their feet, received a strange experience. The ground beneath them was unsteady, quivering a little, telling them that, after all, there was no stability in the earth by which we symbolize stability. They moved across a skin and the organism beneath it was restless.

‘This is abominable,’ said Gaunt. ‘The whole place works secretly. It’s alive.’

‘Look to your right,’ said Dikon. They had come to a hillock; the path divided and, where it turned to the right, was marked by red flags.

‘They told me you used to be able to walk along there,’ Dikon explained, ‘but it’s not safe now. Taupo-tapu is encroaching.’

They followed the white flags, climbed steeply, and at last from the top of the hillock looked down on Taupo-tapu.

It was perhaps fifteen feet across, dun-coloured and glistening, a working ulcer in the body of the earth. Great bubbles of mud formed themselves deliberately, swelled, and broke with the sounds which they had noticed a few minutes before and which were now loud and insistent. With each eruption unctuous rings momentarily creased the surface of the brew. It was impossible to escape the notion that Taupo-tapu had some idiotic purpose of its own.

For perhaps two minutes Gaunt looked at it in silence. ‘Quite obscene, isn’t it?’ he said at last. ‘If you know anything about it, don’t tell me.’

‘The only story I’ve heard,’ Dikon said, ‘is not a pretty one. I won’t.’

Gaunt’s reply was unexpected. ‘I should prefer to hear it from a Maori,’ he said.

‘You can see where the thing has eaten into the old path,’ Dikon pointed out. ‘The red flags begin again on the other side and rejoin our track just below us. Just as well. It would be an unpleasant error to mistake the paths, wouldn’t it?’

‘Don’t, for God’s sake,’ said Gaunt. ‘It’s getting dark. Let’s go home.’

When they turned back, Dikon found that he had to make a deliberate effort to prevent himself from hurrying, and he thought he sensed Gaunt’s impatience too. The firm dry earth felt wholesome under their feet as once more they circled the hill. Behind them, in the native village, a drift of song rose on the cool air, intolerably plaintive and lonely.

‘What’s that?’

‘One of their songs,’ said Dikon. ‘Perhaps they’re rehearsing for your concert. It’s the genuine thing. You get the authentic music up here.’