Both boys were just drifting off into unconsciousness when they were vaguely aware of a car stopping before the door of the house. A moment later a pebble sharply struck the glass of the window, and a low whistle followed this signal.

They were alert and upright at once, and Alan sprang out of bed and went to the window.

“Who’s there?” Alan called softly, sharply from the window.

“That you, Mac?” whispered Keith Washburn softly. “Say Mac, did you leave a light on in the store?”

“Why, no!” said Alan. “Of course not.”

“Are you sure?”

“Abso-tively!” said Alan. “I know because I stumbled over a box of tin things Joe had left in the way.”

“Well, there’s one on there now,” said Keith impressively. “Just saw it as I went by. And what’s more it’s moving around like a flashlight, in the back of the store.”

“Wait a second. I’ll be down!” said Alan, flying into his clothes.

Chapter 4

Don’t get up, Bob,” said Alan struggling into a sweater. “Remember you’ve got a journey to go to tomorrow. It’s likely nothing. Go to sleep. I’ll be back in three jerks of a lamb’s tail.”

“Cut it!” said Bob, jerking on his shoes. “Whaddaya think I am, anyway, Mac?”

Keith was waiting for them downstairs, the engine running softly, and he had the car moving before they were fairly in.

“Sure you weren’t dreaming, Wash?” asked Alan, wondering why his teeth had a tendency to chatter, and trying to remember whether he had finally brought those papers home with him or left them in the safe. He had a ghastly feeling that he had left them in the safe. Oh, if Dad were only well!

“Dreaming!” said Keith contemptuously. “Well, I might have been of course. I saw the light when I first rounded the corner of the post office and I thought it was odd. Thought you must have forgotten to turn it out, or else you decided to leave it burning. But when I got around the front of the store, it was all dark, so I concluded I had been mistaken. Thought it was just a reflection or something. But when I got down to your corner, I looked back, and it flashed up again and moved around. Then I decided you had gone down to the store after something, but somehow I wasn’t easy and thought I’d better see if I could get in touch with you. Thought maybe you could explain it.”

They were rounding the corner into the main street now, and suddenly Bob laid a detaining hand on the wheel.

“Better stop here, Washburn,” he suggested. “If you go nearer, the engine can be heard.”

“That’s right, Lincoln. I ought to have thought of that. I’ll park here in the shadow, and we’ll sneak up. Probably it’s only some trick of the streetlights reflecting somewhere, and I’ll feel like two cents. Probably I’ve only got a case of nerves, riding half the night. If it is, I’ll feel cheap as dirt to think I woke you up, but it’s always just as well to be on the safe side.”

“Sure thing,” said Alan with set lips, as he swung to the ground softly and wondered for the fortieth time whether he had taken those papers home or left them in the safe.

“There is a light in there,” whispered Bob as they stole along, walking on the grass at the edge of the pavement so that their feet made no sound. “There! See there! It’s moving around.