Then, handing her the kitten, he spoke seriously. "What about this island? The green flashes? The big machine on the mountain? The metal thing that jumps about like a grasshopper? What's it all about? You know anything about it?" "Yes, I know a good deal about it," she told him soberly. "It's rather a terrible story. And one you may not believe--no, you've seen them! But the kitten is hungry, and you must be, too, if you swam ashore." "Well, yes, I am." Dan admitted. The storm clouds were drifting out to sea; the sun was beginning to assert itself, and it now lighted up the scene with a cheerful brightness. She slung off her pack and sat down cross-legged at the side of the trail. Dan sat down opposite her as she opened the knapsack and produced a can of condensed milk, one of sardines, a can-opener, and half a loaf of bread. "I had to select my supplies rather at random," she said, "and you'll have to make the best of them." She started to open the sardines. "You'd better give it to me," Dan advised. "You might cut your hand." "You think so?" she asked, deftly lifting the lid, fishing out a fish for the kitten, and presenting the can to Dan. Then with capable hands she broke off a large chunk of bread, which she handed him. "Go ahead and finish this up," she said. "I've already had breakfast." She punched two holes in the end of the milk can, and poured some of the thick yellow fluid into the palm of her left hand, from which she let the kitten lap it. "And now for the mystery of the island," Dan demanded, forgetting bread and sardines in his eagerness. * * * * * The girl turned her face to him. "I'm Helen Hunter, as you seem to know," she began. "I came here with my father five years ago to observe an eclipse of the sun. When it was all over, and the ship called to take us off, he decided to send the results of our observations by one of the other men. He wanted to stay here to carry on another experiment--the one that led to that machine on the hill. Part of the other men were willing to stay. The yacht left us here, and has been back from San Francisco every six months since, with mail and supplies." "And what was the experiment?" Dan demanded eagerly. "Have you ever looked at Mars through a good telescope?" she countered. "Then you must have seen the canals--straight dark lines running from the white polar caps to the equatorial zone. All scientists did not agree as to what they were, but nobody could suggest a natural origin for them. "My father was one of those who thought that the canals were fertile, cultivated strips, irrigated with water brought down from the melting ice-caps. Irrigation systems meant intelligent life upon the planet, and his experiment was an attempt to communicate with that intelligence." "And he succeeded?" Dan was astounded.