The Secret of Mirror Bay by Carolyn G. Keene Page A

Eloise remarked how much they fascinated her and the various things she had learned about them.
    “But I still don’t understand what gives them power to light up and then turn off.”
    Matt smiled. “Perhaps I can help you if you can stand some big words. First of all, a firefly is a beetle and the term lightning bug is probably more appropriate than firefly. Five different chemicals, among them luciferin, are bound together in the abdomen of the beetle. Nerve stimulations release a sixth chemical which breaks up the bond of five. This reaction produces the light. A few seconds later a seventh chemical destroys the sixth one and the light goes out.
    “Scientists are extremely interested in cold light which beetles can produce—but man hasn’t yet been able to! Many deep-sea fish light up, also, and some shrimp, jellyfish, worms, and mollusks.”
    Aunt Eloise asked, “Do many scientists use fireflies in their work?”
    “Yes, in their search for the magic formula of cold heat. I’ve been working on this problem, not with fireflies or anything else living, but with the chemicals which cause the phenomenon. So far I haven’t had much luck, but this year I’m going to concentrate solely on this subject.”
    As Matt paused, the stillness was suddenly shattered by a wild cry on the hillside above the cabin. Then came the sounds of a body hurtling down the hillside.

CHAPTER XIII
    The Vanishing Spook
    EVERYBODY rushed from the porch of the cottage and hurried up the hill. On a level area about halfway to the road lay a young woman.
    “You’re hurt!” Aunt Eloise exclaimed. “We’ll carry you to our cabin.”
    “No, no,” the girl objected. “I got very scared and ran and lost my balance.” She sat up. “I’m all right, really I am.”
    Despite what she said, the stranger was pale and trembling. She was covered with dust and her shoulder-length hair was tousled.
    “Can we take you some place?” Ned spoke up.
    The girl shook her head. “Just help me to the road and please stay until my boy friend comes. He’s going to pick me up. I was early getting off my job at the motel so I started walking toward Cooperstown. I’m Mary Storr.”
    The boys assisted the young woman to her feet while the girls brushed off her clothes. Bess pulled a small comb from her pocket and smoothed the girl’s lovely curly brown hair. Nancy had taken some tissues from a pocket and helped Mary wipe the dirt from her face.
    “My boy friend won’t know me,” Mary said ruefully.
    “What frightened you?” George asked.
    A shiver ran through Mary’s body. “A ghost that came out of the woods. You know, there are spooks around this area. I never heard of a green one, though.”
    “The green man!” Bess exclaimed. “We’ve seen him too.”
    Mary Storr looked startled. “Then I wasn’t dreaming? People tell me that there are no such things as ghosts. I didn’t want to say anything for fear you’d laugh at me.”
    “That green man is no laughing matter,” Bess declared.
    “The figure wasn’t really green,” Mary told them. “It was all in white with a hood. But a funny green light would glow around it for a few seconds, then go off.”
    “Wow! I don’t blame you for being frightened,” Dave spoke up. “Where’d the guy go?”
    Mary Storr said she did not know. “When this white thing started waving its arms toward me like somebody casting a spell, I started to run. I was getting ahead of him, but turned to look back. That’s when I stumbled on something near your path and lost my balance. I started rolling down the hill.”
    By this time the group had reached the road, which was dark. There was no sign of the strange figure.
    “Thank goodness he’s gone,” she said. “And thank you all very much for bringing me up here. You can bet I’ll never walk in this area alone again.”
    As she spoke, headlights appeared in the distance and in a couple of minutes a young man drew up alongside the group. Mary excitedly