Mimi had to give it up.
Alberich put it on his head. "Now I shall see what magic there is in this wishing-cap. Come, Night and Darkness!" he called. "Make me so no one can see me!"
In an instant he was gone, and there was only a cloud of smoke where he had stood.
"Now, Mimi!" he called, "look sharp! Can you see me?"
"No," gasped Mimi. "I cannot see you at all."
The cloud of smoke moved down the gloomy cave and Alberich's cruel voice laughed: "Ha! ha! Now I shall make you black slaves work! Now you dare not be idle, for when you do not see me I shall be watching you!"
His voice sank deeper. "Now I will make you dig, dig, dig, to the very depths of the earth to bring me gold!"
Mimi was so frightened.
When the cloud of smoke had gone out of sight, he lay down upon the rocks and cried.