the hour of twelve
`` We must ! '' said Lanier solemnly . `` Our duty 's to the earth now , man , to the world that we alone can save from the Martian invasion and conquest ! At the hour of twelve Nelson will have the matter-receiver turned on and at that hour the Martian will start flashing to earth -- unless we prevent ! '' Suddenly Randall grasped the knob in his hands more tightly as light showed above them . They had been climbing upward through the enlarged tunnel at their machine 's highest speed , and now as the tunnel curved the light grew stronger . Suddenly they were emerging into the thin sunlight of the Martian day .