walked from the living room,
letting herself out the front door.

Emerging upon the street, Penny's first thought was to find a good
hiding place where she could wait to view Mrs. Dillon's expected caller.

"I may have a tedious time of it," she reflected, "but if I learn the
identity of the agent with whom she dealt it will be worth all the
trouble."

A half block away she noticed a large truck parked along the curbing.
The vehicle had been abandoned, a cracked-up front wheel giving mute
evidence that it had been in an accident. The truck was of the closed
cab type and it dawned upon Penny that if she could get inside, she
would have a perfect observation post.

Luckily the cab of the truck had not been locked and she slipped into
the driver's seat, slamming the door shut.

An hour passed. The job of watching Mrs. Dillon's house became
irksome. No one had called except a peddler and a delivery boy from a
laundry.

Penny tried to pass the time by examining the many gadgets with which
the great truck was equipped. She imagined that it might be loads of
fun to drive such a powerful machine.

Suddenly her attention was arrested by an automobile which with a
shrill screeching of brakes came to a halt in front of the Dillon
residence. A well-dressed middle-aged man, carrying a black leather
brief case, got out of the car.

Penny was sure she had never seen him before. She observed him closely
as he emerged from his automobile. He crossed the street with a quick,
energetic stride as if he knew just where he was going and what he
intended doing after he arrived. She saw him standing patiently at
Mrs. Dillon's door, waiting for a servant to answer his ring.

Was the man the agent Mrs. Dillon had mentioned? The rogue who had
sold the fake painting to the gullible woman? He certainly did not
look like a crook, Penny thought, nor did he act like one. Just one
more reason, she decided, why she must take nothing for granted. She
produced a notebook and pencil from her purse and made a careful
notation of the stranger's automobile license number as well as its
make and model.

For perhaps forty-five minutes the man remained inside the house. When
he crossed the street to his car he skipped along with an agility
surprising in a man of his years. He smiled broadly as if his mission,
whatever it may have been, was successful. Scarcely had he driven away
when another automobile swung into the same parking spac