He had faith in Curdie, and rose instantly, with Irene in his arms.
'Every man and woman follow me,' he said, and strode out into the darkness.
Before he had reached the gate, the noise had grown to a great thundering roar, and the ground trembled beneath their feet, and before the last of them had crossed the court, out after them from the great hall door came a huge rush of turbid water, and almost swept them away.
But they got safe out of the gate and up the mountain, while the torrent went roaring down the road into the valley beneath.
Curdie had left the king and the princess to look after his mother, whom he and his father, one on each side, caught up when the stream overtook them and carried safe and dry.
When the king had got out of the way of the water, a little up the mountain, he stood with the princess in his arms, looking back with amazement on the issuing torrent, which glimmered fierce and foamy through the night.

There Curdie rejoined them.
'Now, Curdie,' said the king, 'what does it mean?
Is this what you expected ?' 'It is, Your Majesty,' said Curdie; and proceeded to tell him about the second scheme of the goblins, who, fancying the miners of more importance to the upper world than they were, had resolved, if they should fail in carrying off the king's daughter, to flood the mine and drown the miners.

Then he explained what the miners had done to prevent it.

The goblins had, in pursuance of their design, let loose all the underground reservoirs and streams, expecting the water to run down into the mine, which was lower than their part of the mountain, for they had, as they supposed, not knowing of the solid wall close behind, broken a passage through into it.

But the readiest outlet the water could find had turned out to be the tunnel they had made to the king's house, the possibility of which catastrophe had not occurred to the young miner until he had laid his ear to the floor of the hall.
What was then to be done?
The house appeared in danger of falling, and every moment the torrent was increasing.
'We must set out at once,' said the king.