Free Through the Hidden Door by Rosemary Wells

some bluish ... paint?”
    “Right. Now look at this.” I put another chip next to the others.
    “Same thing. Paint, or whatever it is, is black, though.”
    I pocketed both. “You know that fake Greek vase in the main hall, Snowy?”
    “Yes, I know the one. How do you know it’s fake?”
    “Are you kidding? A forty-gallon amphora, black figures on red, in perfect condition? The thing would be in the Metropolitan Museum of Art if it were real. They keep it full of dried cattails and straw flowers. Even Silks isn’t that dumb. If it were an antique, the school could sell it and buy two swimming pools and a domed stadium.”
    “How do you know?”
    “My dad’s an antiques dealer. He knows all about that stuff.”
    “My dad’s a colonel in the Marine Corps.” Snowy growled, as if I had challenged him to a fight.
    “Okay,” I said gently. Snowy looked angry. I waited for him to say something, but he didn’t, so I went on. “Well, I just chipped a little off the back of it with my knife. The vase chip matches these. They’re both baked clay. Snowy, somewhere in that cave are remains of glazed pottery.”
    “But where did you find the four little chips? When? Last night on your socks?”
    “That’s the thing of it. There was nothing on last night’s socks. I checked them carefully before we left the cave. I would have seen these bits right away. They’re a different color from the sand. I found them when I washed my hands and they fell off in the sink.”
    Snowy blindfolded me. We began our trek.
    “What did you do before you washed your hands?”
    “Took off my clothes. Threw ’em in the laundry pile. Listen, nothing could have stuck to my clothes. Only my socks, and my socks were clean. Just sand. I shook them out. There wasn’t anything.”
    “Go over it again.”
    I let out an impatient sigh. “Okay. I took off my socks. Right? Then my shirt. Covered with mud from the tunnel. Then my pants. That’s it.”
    “And turned out the pockets like a good boy?” asked Snowy.
    “What? Sure. Wait a minute ... pockets ...
    “Was that the last thing you did before you washed your hands? Turned out the pockets of your pants?”
    “Yes! Damn!” I said. “Except for another pair of socks ... I took them out of my parka pockets. The socks from the first day across the river. They were frozen, and I didn’t put them on again. Snowy, they came from somewhere in our very first squares. We didn’t walk long that day. I remember about where we were.”
    “We’re on our way, Barney!” Snowy said. I could hear the smile in his voice.
    We plowed through our original squares for nearly an hour and a half. By that time we had piled up a dozen sand mountains as high as our knees.
    “Look at that,” said Snowy, panting and exhausted. “We’ve thrown sand over where we might want to dig next. How do we get the stupid piles out of the way?”
    Worse, every hole filled in as quickly as we dug it. The swiftly collapsing sides kept slipping back into the pits. “Another complete loss!” Snowy grumbled, throwing his trowel away. “We should have brought shovels.”
    I was about to suggest that next time he should order an Army Corps of Engineers bulldozer from the back pages of Soldier of Fortune when the tip of my trowel touched something hard at the very bottom of the hole. “At least it’s ground, if nothing else. The sand can’t go down forever,” I muttered.
    Then we both dug fast and deep. “My knees are freezing,” said Snowy. We realized that to get any deeper, we’d have to dig very wide around where we wanted to go, to keep the sandy sides from falling in on themselves.
    We cleared away as much sand as we could. Then we started pushing back the huge mound that lay all around us. I stopped with the trowel, lay on my belly, and felt with my fingers. It was just possible as the hole was the depth of my outstretched arm. I pulled my pocketknife from my jeans and, stomach pressed into the frigid sand,