Now as the days passed, a change crept over those who dwelt in the castle.
Huldbrand saw that Bertalda seemed to shrink away from his beautiful wife. And when at length he asked her the reason that she no longer loved Undine so well as she had been used to do, she told him that she now knew from whence his wife had come. 'And for the spirit world,' said Bertalda, 'I do not care, for I know it not. It and those who have dwelt there fill me with fear and dread.'
Little by little the knight himself began to look at his wife with less loving eyes, little by little he began to shun her presence.
Then Undine, seeing that her husband's love grew less, wept, and the knight, seeing her tears, would speak kindly to her, yet even as he spoke he would leave her side to walk with Bertalda.
She, Bertalda, meanwhile grew once more rude and proud, nor could Undine's patience win her to behave more wisely.
Then in the long dark passages of the old castle, spectres began to appear to Huldbrand and Bertalda, and worse than any was the tall form of Kühleborn, or the Master of the fountain, as the maiden still called him.
Now one day, when Huldbrand had ridden to the hunt, Undine gathered all her servants together in the court of the castle and bade them bring a big stone to cover up the fountain which stood in the middle of the square.