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.
The servants, who loved their mistress, hastened to obey her commands. A huge stone was carried into the court, and was just about to be placed on the fountain when Bertalda came hurriedly to the spot.
'The fountain must not be closed,' she cried haughtily, 'for it is from it that water is drawn for my daily bath.'
But Undine, who on other days had often given way to the wishes of Bertalda, was to-day determined that her will should be done.
'It is I who am mistress of the castle in the absence of my lord,' she said, and her voice was firm though it was kind, 'and the fountain shall be closed as I have commanded.'
'But look,' cried Bertalda angrily, 'the water itself bubbles and heaves as though disturbed at the thought of being shut out from the glad sunshine.'
The water was indeed, as the maiden said, fretting against the stones and throwing out sudden jets as though in a violent passion.
The more excited grew the water, however, the more determined grew Undine to have her order fulfilled, and that without delay.