He glanced up as Garin joined him. "You are late," he accused. "But your excuse is a good one. Now get you to work. Hold this here—and here—while I fasten these clamps."

So Garin became extra hands and feet for Dandtan, and they worked feverishly to build against the lifting of the Mists. There was no day or night in the laboratories. They worked steadily without rest, and without feeling fatigue.

Twice they went to the Chamber of Renewing, but except for these trips to the upper ways they were not out of the laboratories through all those days. Of Thrala there was no sign, nor did any one speak of her.

The Cavern dwellers were depending upon two defenses: an evil green liquid, to be thrown in frail glass globes, and a screen charged with energy. Shortly before the lifting of the Mists, these arms were transported to the entrance and installed there. Dandtan and Garin made a last inspection.

"Kepta makes the mistake of under-rating his enemies," Dandtan reflected, feeling the edge of the screen caressingly. "When I was captured, on the day my people died, I was sent to the Black Ones' laboratories so that their seekers after knowledge might learn the secrets of the Ancient Ones. But I proved a better pupil than teacher and I discovered the defense against the Black Fire. After I had learned that, Kepta grew impatient with my supposed stupidity and tried to use me to force Thrala to his will. For that, as for other things, shall he pay—and the paying will not be in coin of his own striking. Let us think of that...." He turned to greet Urg and Trar and the other leaders of the Folk, who had approached unnoticed.

Among them stood Thrala, her gaze fixed upon the crystal wall between them and the thinning Mist. She noticed Garin no more than she did the Anas playing with her train and the women whispering behind her. But Garin stepped back into the shadows—and what he saw was not weapons of war, but cloudy black hair and graceful white limbs veiled in splendor.

Urg and one of the other chieftains bore down upon the door lever. With a protesting squeak, the glass wall disappeared into the rock. The green of Tav beckoned them out to walk in its freshness; it was renewed with lusty life. But in all that expanse of meadow and forest there was a strange stillness.

"Post sentries," ordered Dandtan. "The Black Ones will come soon."

He beckoned Garin forward as he spoke to Thrala:

"Let us go to the Hall of Thrones."