"Then aren't you afraid----?"

"Not in the least," Mrs. Dillon interrupted. "Naturally, the dealer wouldn't subject himself to arrest by acknowledging that he was selling stolen property."

"The painting is a very fine one," the other woman declared, "but I can't say I should care to own it myself. You'll never be able to display it openly."

"Perhaps not, but I can show it privately to my friends and I'll derive satisfaction just from knowing I own it."

"But if the police should suspect----"

"They won't, unless someone reports me. So far you are the only person who knows that I have the painting."

"Oh, you may trust me, Mrs. Dillon. I'll never give you away."

"If the picture should ever be traced to me I can always claim that I was an innocent purchaser," Mrs. Dillon chuckled. "In fact, I don't know that this is the same picture that was taken from the Gage Galleries. The dealer didn't tell me that it was an original."

"You're very shrewd," the other woman praised.

Mrs. Dillon carefully drew the velvet curtain over the painting and closed the panel. As the two women moved toward the door they pa.s.sed close to Penny's chair. The girl held her breath, fearing detection.

She had not meant to be an eavesdropper, but the nature of Mrs.

Dillon's conversation had made it impossible to reveal her presence in the room without creating a difficult scene. However, should she be discovered now, crouching behind the back of the chair, the situation would prove even more embarra.s.sing.

"We must return to the others before we're missed," Mrs. Dillon said, unlocking the door.

The two women went out, and Penny heard a slight metallic click which at the moment did not strike her as having any significance. As the door closed she quickly arose from her chair.

Penny was dismayed at what she had seen and heard. It was difficult for her to believe that Mrs. Dillon owned the painting which had been stolen from the Gage Galleries. From the conversation she felt quite sure that the society woman had purchased the picture from a dishonest dealer who undoubtedly had received it from the original thief. Yet Mrs. Dillon had knowingly purchased stolen property and so in effect was an accessory to the crime.

"She must be crazy to involve herself in a deal like that," Penny thought. "If the police learn she has the painting they'll confiscate it and arrest her."

Penny realized that she had it within her power to expose Mrs. Dillon.

Even though she were a guest in the society woman's home, it was really her duty to reveal her findings to the police.

From her hiding place behind the chair, Penny had not been able to secure a very good view of the painting. She was eager to examine it at close range.

Did she dare open the panel? She decided to take the chance. Jerking at the long silken rope as she had seen Mrs. Dillon do, the girl was gratified to observe the sham picture above the mantel swing slowly back to reveal the hidden panel.

Penny quickly drew aside the velvet curtain which protected the stolen Rembrandt.

The painting was one of the lesser known works of the famous artist, a picture of a child. Penny snapped on the electric light that she might view it to better advantage.

At first glance the painting was very impressive, but as the girl studied it more critically, she was a.s.sailed with doubt. The picture did not seem to have the character or strength commonly a.s.sociated with great works of art. The draftmanship seemed mechanical, the color lacked depth.

"I wonder if it really is a genuine Rembrandt?" Penny thought.

The longer she gazed at it the more convinced she became that the picture was merely a clever imitation. She wished that Amy Coulter were there to offer an opinion. Penny did not trust her own judgment.

Her knowledge of art was so slight that she might be mistaken in considering the Rembrandt a fraud.

Closing the panel, Penny sat down for an instant to think. She knew she had made an important discovery, one which easily could cause Mrs.

Dillon serious trouble should she report her findings to the police.

Upon the other hand, the society woman was an important personage of Belton City with many influential friends, and should she be falsely arrested the trouble would descend like an avalanche upon the head of Penny Nichols.

"I'll have to move cautiously," the girl reflected. "It's no crime to own a copy of a stolen painting. If this picture is a fake, the police would have no case against Mrs. Dillon."

The problem was too deep for Penny. She decided to reveal to no one the discovery she had made until after she had discussed the matter with her father. Quickly, she arose and went to the door.

To her surprise it did not open when she turned the k.n.o.b. It took an instant for the truth to dawn upon her. The door was locked!

"Mrs. Dillon must have turned the key when she went out," Penny thought, recalling that she had heard a slight metallic click. "Now I am in it!"

She considered calling for help but immediately abandoned the idea. It would be difficult to explain how she had been locked in the library without revealing the true details. And Mrs. Dillon would instantly suspect that she had seen the hidden painting.

The room had two windows looking out upon the front lawn. Directly beneath was a cultivated bed of flowers which Penny decided must be sacrificed if necessary to the occasion. She switched out the electric lights, and raising one of the windows peered in both directions to see that the coast was clear.

Quickly she climbed over the sill, hung by her fingers tips for an instant, then dropped lightly down to the ground, crushing several choice plants underfoot.

Before she could turn she felt her arms pinioned behind her back in a grasp of steel.

"Not so fast, young lady!" said a gruff voice.

Penny whirled around to face the man who had captured her. She began to laugh.

"Dad!"

"Penny! I thought I had caught a young lady burglar. What are you trying to do?"

"Escape from the library."

"So I observe. But have you any objection to using a door? In polite society I believe that's the accepted method of leaving a house."

"The library door was locked," Penny explained hastily. "And I have good reason for wanting to get away without being seen by anyone."

"In that case, always close the window after you," Mr. Nichols chuckled. "Here, I'll boost you up and you can pull it down."

After Penny had lowered the sash, they hurriedly moved away from the window.

"Now tell me all about it," the detective invited. "Did you lose your bag of loot?"

"You know very well I wasn't doing anything I shouldn't," Penny countered, "but you nearly frightened me to death when you nabbed me."

"I just happened to see you climbing out of the window as I came up the path," the detective smiled. "I thought perhaps someone was escaping with the family jewels."

"Speaking of jewelry, there's plenty of it around tonight. The ballroom is fairly ablaze with it."

"Never mind the jewelry," Mr. Nichols said. "What were you doing in the library?"

Leading her father to a secluded stone bench in the garden, Penny related all that she had seen and heard.