But somehow the desire to pick up gems which, when they were cut and polished, would rival many of the famous diamonds of history was too strong to be resisted. Though he was afraid he would never get back to earth to enjoy them, Jack could not help putting in his pockets a goodly supply of the largest of the precious stones. Andy did the same, and Mark, in spite of his gloomy feelings, stuffed his pockets. They worked with their torches held close to their faces, and in the search for the better stones they literally walked over millions of dollars' worth of the gems. For there, stretched out before them, was an actual field of diamonds. As Mark had said, they were of meteoric origin, that is, a meteor had burst over that particular portion of the moon, and the chemical action had created the diamonds, which had fallen in a shower in the field. "If you boys have all you want, then let's get back to the city," suggested Andy. "No telling when it will be night now." They followed his advice, and soon were going back by way of the black pool. It seemed more lonesome than ever, after the excitement of discovering the field of diamonds, and even Jack, glad as he was to have his theory vindicated, got tired of referring to it. His triumph meant little to him now. They were at the entrance to the petrified city. As they were about to go in, ready to hide themselves in the deepest part of the restaurant, away from the terrible cold and appalling darkness they felt would soon be upon them, Mark came to a sudden halt. He glanced quickly up into the air and cried out: "Hark!" "What's the matter?" asked Jack, as they stood in a listening attitude. "I heard a noise," whispered Mark. "It sounded--I'm sure it sounded--like the crackling of the wireless motor waves of the projectile. Listen!" Faintly through the silence came a sound as if there was a discharge of an electric current. It increased in volume, and there was a faint roaring in the atmosphere. "It's her--it's the _Annihilator!_" shouted Jack, leaping about. "Wait," counselled Andy, who dreaded the terrible disappointment should the boys be mistaken. The sound came nearer. The crackling could plainly be made out now. The sun was out of sight, but there was still the glow which follows sunset. The boys were eagerly scanning the heavens, Their hearts beat high with hope. Suddenly, in the olive-tinted sky just above a range of rugged peaks, a black shape loomed. A black shape, as of a great cigar, pointed at both ends. It shot into full view. "The projectile!" yelled Jack. "The _Annihilator!_" gasped Mark. "Thank Heaven, they have found us in time!" exclaimed Andy fervently, and the three stretched out their arms toward the craft from which they had been parted so long. It was as if they tried to pull it down to them. "Do they see us?" "Will they pass us by?" "Make a noise so they'll hear us!" "Wave to them!" "Oh, if they leave us now!"