"When they had had enough they began to search the castle once more, but they soon felt sleepy, so they lay down in one of the rooms where they found beds all ready for them, and fell fast asleep.
"No sooner were they asleep than Bourdon's three cousins, Bass, Violone, and Ophicleide, who were looking after the castle for him, and who had been hiding in a secret room in the walls, came out and bound them and cast them into an oubliette which was at the bottom of the castle, right under the lake. And there they found Vox Angelica, Dolce, Muzette, and Clarabella.
"To go back to Lieblich Gedacht: he was of course miserable, and he spent a whole month in the willow-tree, waiting for Hautboy and the others to come to set him free. But they never came. At last one day he remembered the walnut which Sackbut had given him. He had quite forgotten it up to that moment. He took it out of his pocket and cracked it, and in it he found a tiny silver key and a hazel nut. He put the hazel nut in his pocket, and he looked everywhere in the tree for a keyhole, and at last he found a tiny crack; he put the key in the crack and it fitted exactly. The door of the tree opened and he was free once more. He set out for the lake at once, and reached it in a few hours. Exactly the same things happened to him as to the others. The boat took him across the lake. He entered the empty castle and explored every nook and corner of it, but he found nothing. When he came into the banqueting-hall he saw the table spread by invisible hands; but he said to himself: 'I will not eat and drink till I have found Vox Angelica.' So he did not touch the food; but he went on searching. As he was looking out of one of the windows of the castle he distinctly heard Vox Angelica's sigh coming from the lake, and he at once understood that she was imprisoned in some dungeon underneath the lake. He waited until it was dark, and then he took the boat and rowed round the castle, and low down by the water he came to a barred window, and from this window came the sound of many sighs. Lieblich Gedacht now understood why the lake was called the Lake of Sighs, for the sighs came from prisoners imprisoned in Bourdon's dungeon.
"'Is that you, Vox Angelica?' he whispered.
"'Yes,' she whispered back, 'we are all here in the dungeon. But you must be careful, because Bourdon's three brothers are hiding in the castle.'
"'How can I rescue you?' asked Lieblich Gedacht.
"'I don't know,' said Vox Angelica. 'We are all of us bound in fetters.'
"'I will try and find a file,' said Lieblich Gedacht, 'to file the bars of the window and set you free.'
"So he went back to the castle to look for a file, but as he entered the gate Bourdon's three brothers fell upon him, and bound him, and cast him into the dungeon.
"'Alas!' said Vox Humana, 'we are all lost now.'