And then, loud and clear in his helmet speaker, came a sound so utterly unexpected that the waves of panic ceased to batter against the island of his soul. It was Tom Lawson—laughing.

The laughter was brief, and it was followed by an apology.

“I'm sorry, Mr. Lawrence—I couldn't help it. You look so funny there, waving your legs in the sky.”

The Chief Engineer froze in his suit. His fear vanished instantly, to be replaced by anger. He was furious with Lawson, but much more furious with himself.

Of course he had been in no danger; in his inflated suit, he was like a balloon floating upon water, and equally incapable of sinking. Now that he knew what had happened, he could sort matters out by himself. He kicked purposefully with his legs, paddled with his hands, and rolled round his center of gravity—and vision returned as the dust streamed off his helmet. He had sunk, at the most, ten centimeters, and the ski had been within reach all the time. It was a remarkable achievement to have missed it completely while he was flailing around like a stranded octopus.

With as much dignity as he could muster, he grabbed the ski and pulled himself aboard. He did not trust himself to speak, for he was still breathless from his unnecessary exertions, and his voice might betray his recent panic. And he was still angry; he would not have made such a fool of himself in the days when he was working constantly out on the lunar surface. Now he was out of touch. Why, the last time he had worn a suit had been for his annual proficiency check, and then he had never even stepped outside the air lock.

Back on the ski, as he continued with his probing, his mixture of fright and anger slowly evaporated. It was replaced by a mood of thoughtfulness, as he realized how closely—whether he liked it or not—the events of the last half-hour had linked him with Lawson. True, the astronomer had laughed when he was floundering in the dust, but he must have been an irresistibly funny sight. And Lawson had actually apologized for his mirth. A short time ago, both laughter and apology would have been equally unthinkable.

Then Lawrence forgot everything else; for his probe hit an obstacle, fifteen meters down.

CHAPTER 14

When Mrs. Schuster screamed, Commodore Hansteen's first reaction was: My God—the woman's going to have hysterics. Half a second later, he needed all his will power not to join her.

From outside the hull, where there had been no sound for three days except the whispering of the dust, there was a noise at last. It was unmistakable, and so was its meaning. Something metallic was scraping along the hull.

Instantly, the cabin was filled with shouts, cheers, and cries of relief. With considerablc. difficulty, Hansteen managed to make himself heard.

“They've found us,” he said, “but they may not know it. If we work together, they'll have a better chance of spotting us. Pat, you try the radio. The rest of us will rap on the hull—the old Morse V sign—DIT DIT DIT DAH. Come on—all together!”

Selene reverberated with a ragged volley of dots and dashes, which slowly became synchronized into one resounding tattoo.

“Hold it!” said Hansteen a minute later. “Everyone listen carefully!”

After the noise, the silence was uncanny—even unnerving. Pat had switched off the air pumps and fans, so that the only sound aboard the cruiser was the beating of twenty-two hearts.

The silence dragged on and on. Could that noise, after all, have been nothing but some contraction or expansion of Selene's own hull? Or had the rescue party—if it was a rescue party—missed them and passed on across the empty face of the Sea?

Abruptly, the scratching came again. Hansteen checked the renewed enthusiasm with a wave of his hand.

“Listen, for God's sake,” he entreated. “Let's see if we can make anything of it.”

The scratching lasted only for a few seconds before being followed once again by that agonizing silence. Presently someone said quietly, more to break the suspense than to make any useful contribution, “That sounded like a wire being dragged past. Maybe they're trawling for us.”

“Impossible,” answered Pat. “The resistance would be too great, especially at this depth. It's more likely to be a rod probing up and down.”

“Anyway,” said the Commodore, “there's a search party within a few meters of us. Give them another tattoo. Once again—all together—”

DIT DIT DIT DAH .. ..

DIT DIT DIT DAH .. ..

Through Selene's double hull and out into the dust throbbed the fateful opening of Beethoven's Fifth Symphony, as a century earlier it had pulsed across Occupied Europe. In the pilot's seat, Pat Harris was saying again and again, with desperate urgency, “Selene calling. Are you receiving? Over,” and then listening for an eternal fifteen seconds before he repeated the transmission. But the ether remained as silent as it had been ever since the dust had swallowed them up.

Aboard Auriga, Maurice Spenser looked anxiously at the clock.