But now all that was finished. The radio-active ore was sufficiently concentrated. It lay--this treasure--in a seventy-foot pile behind the glassite lean-to, with a cage of wires over it and an insulation barrage guarding its Gamma rays from escaping to mark its presence. The ore-shelter was dark; the other two buildings were lighted. And there were small lights mounted at intervals about the camp and along the edge of the ledge. A spider ladder, with tiny platforms some twenty feet one above the other, hung precariously to the cliff-face. It descended the five hundred feet to the crater floor; and, behind the camp, it mounted the jagged cliff-face to the upper rim-height, where a small observatory platform was placed. * * * * * Such was the outer aspect of the Grantline Treasure Camp near the beginning of this Lunar night, when, unbeknown to Grantline and his score of men, the _Planetara_ with its brigands was approaching. The night was perhaps a sixth advanced. Full night. No breath of cloud to mar the brilliant starry heavens. The quadrant Earth hung poised like a giant mellow moon over Grantline's crater. A bright Earth, yet no air was here on this Lunar surface to spread its light. Only a glow, mingling with the spots of blue tube-light on the poles along the cliff, and the radiance from the lighted buildings. The crater floor was dimly purple. Beyond the opposite upper rim, from the camp-height, the towering top of distant Archimedes was visible. No evidence of movement showed about the silent camp. Then a pressure door in an end of the main building opened its tiny series of locks. A bent figure came out. The lock closed. The figure straightened and gazed about the camp. Grotesque, bloated semblance of a man! Helmeted, with rounded dome-hood suggestion of an ancient sea diver, yet goggled and trunked like a gas-masked fighter of the twentieth century war. He stooped presently and disconnected metal weights which were upon his shoes.[E] Then he stood erect again, and with giant strides bounded along the cliff. Fantastic figure in the blue-lit gloom! A child's dream of crags and rocks and strange lights with a single monstrous figure in seven-league boots. He went the length of the ledge with his twenty-foot strides, inspected the lights, and made adjustments. Came back, and climbed with agile, bounding leaps up the spider ladder to the dome on the crater top. A light flashed on up there. Then it was extinguished. The goggled, bloated figure came leaping down after a moment. Grantline's exterior watchman making his rounds. He came back to the main building. Fastened the weights on his shoes. Signaled within. The lock opened. The figure went inside.