Jack had taken the lead, and was walking along, glancing idly about. He came to a place where two peaks were so close together that it was all he could do to squeeze through. But the moment he had passed the defile and looked out on a broad, level field, he came to a sudden stop. His companions, who pressed after him, saw him rub his eyes and shake his head, as if disbelieving the evidence of what lay before him. Then Jack murmured: "It can't be true! It can't be true!" "What?" called Mark. "There! Those," answered his chum. "See, the field is covered with diamonds! We have found the diamonds of the moon--the field of Reonaris that the men of Mars discovered! There are the diamonds--millions of them!" "Diamonds!" exclaimed Mark. He squeezed through the defile, and stood beside Jack. Before him in the fading light of the sun was a broad field, girt around with towering cliffs, and the surface of the field was covered with white stones. Jack sprang forward and gathered up a double handful. He let them run through his fingers in a sparkling stream. Old Andy came up to the boys. "They're only glass or crystals," he said. "They are _not_ glass or crystals!" declared Mark, who had made a study of gems. "I should say they were diamonds, probably meteoric diamonds, very rare and valuable. Why, there is the ransom of a thousand kings spread out before us!" He fell upon his knees and began to scoop up the gems. His chum was making a little heap of the stones. "The ransom of a thousand kings!" murmured Jack. "More diamonds than in all the world--and I'd give my share for a good ham sandwich!" CHAPTER XXX BACK TO EARTH--CONCLUSION At any other time the discovery of such a vast store of wealth would have set the wanderers half wild with joy. Now they only accepted the fact dully, for the perils of their situation overburdened them. As Jack had said, they needed food more than the gems, for at best the supply they had blasted out could not last long, and when that was gone where were they to get more, for there were no more cartridges, and the rending force of powder was needed to open the rocky meat. "I knew we'd find the diamonds," murmured Jack, as he began to fill the pockets of his fur coat. "I'm right, after all, Mark, you see." "Yes, but what good will it do us? What's the good of even carrying any away. We can never use them." "That's so," agreed Jack, in a low voice. "I might as well leave them here."