“There, slow!” cried the king, and then a frightful scene burst upon their sight. They beheld a great belching pit of fire and flames. The sky from the earth to the zenith was a vast expanse of illuminated smoke, and the black landscape round about was cut by rivulets of molten lava rolling on and on like restless streams of quicksilver. The king leaned against the stand as if faint with despair. “Call Prince Arthur!” he ordered, and almost at that instant the young man appeared. “Father!” The king pointed a quivering finger at the mirror, and said huskily: “Let not the sun go down! Let its light be white as at noon.” “But, father, it has never been done before; it----” “Alpha has never faced such danger. All our dream is about to end. Go!” Without a word the young man hastened away, and it seemed scarcely a moment before the sunlight streaming in at the oval glass roof changed from green to white. The king pushed Ornethelo impatiently aside; his eyes held a dull gleam of despair, and he seemed to have grown ten years older. He touched a button, and the awful scene at the pit gave place to a bright view of the capitol, which was plainly seen from its crowded centre to its scattering suburbs. The squads of “protectors” stood like armies ready for battle, their rigid faces still toward the awful west. “They are ready--the signal!” yelled the king, waving his hand, “the signal!” Ornethelo caught his breath suddenly and tottered as he went across the room, and touched a button on the wall. The king's eyes were glued on the mirrored view of the capitol, his trembling hands held out, as if commanding silence. Then a deafening trumpet blast broke on the ear. The masses of citizens pressed near the edges of the roofs and close against the walls along the streets, as the protectors rushed into the flying-machines. Another trumpet-blast, and away they flew, a long black line, every instant growing smaller as it receded in the murky distance. The princess, white and silent, led Thorndyke and Johnston back to the balcony. The line of machines was now a mere thread in the sky, but the ominous cloud in the west had increased, and fine sand and ashes were added to the fall of soot. “What was that?” gasped the princess. It was a low rumble like distant thunder, and the balcony shook violently. “An earthquake,” said Thorndyke. “I am really afraid there is not a ghost of a chance for us; the water running into the fire is sure to cause an eruption of some sort, and even a slight one would be likely to enlarge the opening to the ocean.” Johnston nodded knowingly as he looked into his friend's face, but, considering the presence of the princess, he said nothing. “My brother, Prince Marentel, is the greatest man in our kingdom,” she re marked. “He has taken enough explosives to remove a mountain.” “How will he use them?” asked Thorndyke. “I don't know, but I fancy he will try to close the opening in some way.”