The Mystery of the Castaway Children

the girls caught sight of the sparkling blue lake. They hopped about on the hot boards of the dock just long enough to remove their sneakers, then they dived in at the same time. By the third stroke, Honey had pulled ahead of Trixie.
    After a few minutes of porpoiselike splashing and playing, Trixie decided, “I still feel sticky. I’m going to shore for the soap.”
    Honey flipped over and floated lazily. “Toss it to me when you’re through.”
    Chunks of soap were kept in a covered plastic carton nailed to the edge of the dock. When Trixie reached for the top bar, she found that the bottom of it was wet. That’s odd, she thought. There were drainage holes punched in the plastic carton. All the soap should be bone-dry.
    Trixie waded back in, ducked under, lathered her arms, and ducked again. She was more thorough in her second lathering and took time to study the shores of the small lake, watching for movements. She saw none.
    Trixie swam out far enough to lob the bar to Honey. “Has anybody been swimming this morning?” she asked.
    “Not that I know of,” Honey said as she lathered her own hands and arms. After she rinsed, she said, “Reflections from the water are going to give us a dandy sunburn pretty soon. We’d better go to shore.”
    Trixie pointed to the opposite side of the lake. “I see a nice shady spot where we could rest.”
    Honey agreed, and the girls paddled to shore, where they jumped from stone to stone until they found a rock large enough to stretch out on.
    “I could stay here all day if I wasn’t so hungry,” sighed Trixie as she got herself comfortable.
    “Me, too. The only thing is, we’re not making things come out right,” Honey complained. “Our sneakers and bicycles are at the boathouse, and the soap is over here.”
    “If Mart were here, he’d spout quotations,” Trixie said.
    “A rolling stone gathers no soap?” Honey suggested helpfully.
    Trixie snorted, then recited triumphantly, “When we have not what we like, we must like what we have.”
    “I’ll buy that,” Honey declared.
    For the moment, Trixie liked what she had. She lay on her stomach, chin propped on folded arms. Blue sky, tall pines, and flowing water combined to give her a feeling of total isolation. Lining the Hudson not far away were brickyards and cement factories, automotive assembly plants, railroads and highways. Here in the woods, the earth was undisturbed. Trixie liked it that way, especially when she had a puzzle that needed to be worked out.
    She squinted through sandy lashes, and the whole scene went slightly out of focus. A glare of light was bothersome. After a minute, she got up impatiently.
    “Do we have to go now?” Honey asked. “I wasn’t planning on moving a muscle for at least six months.”
    “I just want to pick up something over there,” Trixie said. She sprinted into the woods to see what was littering one of her favorite spots. It turned out to be a glass bottle... with ounce-levels marked!
    “Honey!” she shrieked. “I’ve found one of Dodgy’s bottles!”
    Honey waved a lazy hand. “Bobby must have carried off one of the baby’s bottles to catch minnows or something,” she mumbled.
    Trixie ran back and squatted beside Honey. “This isn’t one of the disposable bottles you bought. Honey, it’s glass—and there’s dried milk in the bottom!”
    Honey was forced to pay attention. Suddenly she said, “If this is Dodgy’s bottle, it means that whoever left him in the doghouse could still be hanging around.”
    “Jeepers!” whispered Trixie. “And the soap in the plastic carton was wet, like somebody’d used it.”
    Quietly the girls turned from side to side, searching for signs of another human being. They saw nothing, but Trixie urged, “Let’s have a closer look.”
    Back she hopped to the edge of the lake. Carefully she examined the whole area. “There’s crushed grass,” she called to Honey, who was working her way toward the woods. “And some kind of pushed-in places. Come and look.” Honey obliged. It was she who found a dime and two pennies in the mashed grass. “Sit down here and put your heels in those little holes,” she commanded.
    “I see what you mean!” Trixie exclaimed. “Someone sat here by the brook and dug in his heels. He lost the coins out of his pockets. You know, I’ll bet it was Davy who sat here and lost this money.”
    “Couldn’t it have been the kidnapper?” Honey asked.
    “The heel marks are too small for