“You can say that again,” Sandy murmured.
“So we can’t do much about it until everybody’s in bed.” Ken looked down at his new watch. “I can’t tell if it’s quarter to nine or December twenty-fourth.”
“It might be both,” Sandy said helpfully.
“By gum, I believe you’re right.” They grinned at each other briefly. “O.K.,” Ken said then, “you have just proved what I always suspected—that you’re the mechanical genius in this outfit. You figure it out.”
“What’s difficult about it? We leave the chains off both doors. We sit in utter darkness—in the living room, say, where we couldn’t possibly be seen by anybody entering either door. And when somebody comes in—if somebody comes in—” His involved sentence broke off in a vast yawn.
Ken yawned too. “He finds us,” he said, when he could speak, “fast asleep. He takes the box. He departs.” He sat up and shook himself. “That is not my idea of a booby trap.”
The timer bell rang just then, and for the next several minutes they were busy. The activity roused them a little, but before the films were hanging from their drying clips both Ken and Sandy had yawned again.
Sandy tried to examine the tiny strip of film with a magnifying glass. “It looks great,” he muttered. “Wish it were dry already, so I could try printing them up. Wonder how big an enlargement I’ll be able to make.”
“Look,” Ken said, “don’t start getting any ideas about staying down here half the night to work on them. If the rest of the family is half as sleepy as we are, they’ll be turning in early tonight. And we’d better be there if we really want to watch for a visitor.”
“All right,” Sandy agreed. “I’m coming. I offer only one slight correction to your theory. We’d better be there—with a cup of coffee.”