agent, Mrs. Dillon?"

"That I cannot tell you. I promised never to reveal his name."

"But it is your duty to do so," Penny urged. "I have every reason to
believe that this man has cheated you."

"I will not give his name," Mrs. Dillon repeated firmly.

"He is a special friend of yours?"

"Perhaps."

"I appreciate your motive in trying to shield him," Penny said, "but
the matter is serious. This man has sold you a worthless picture,
representing it to be a stolen Rembrandt."

"The painting is genuine," Mrs. Dillon insisted. "I have proof of it."

"What proof, may I ask?"

"The picture was viewed by an expert--a man whose judgment I trust
implicitly. He assured me that it was genuine."

"This expert looked at your picture since it was delivered to the
house?"

"No, at the studio."

"What studio?" Penny asked quickly.

"I will tell you if you promise not to betray me to the police."

"I came here today because I wanted to help you, Mrs. Dillon. I have
no intention of going to the authorities if it can be avoided."

"The studio is on Franklyn Street," the woman informed. "On an upper
floor."

"Do you have the exact number of the building?" Penny asked quickly.

"Yes, somewhere."

Mrs. Dillon went to her desk and after examining a number of papers
found an old envelope upon which she had written the address. Penny
glanced at it and a look of disappointment came over her face.

"Oh, this clue will do no good!" she exclaimed. "I know about this
place. The men have gone. They moved out last night--secretly."

The address was the same building which Penny had investigated that
afternoon.

"Can you describe the person or persons whom you met in the studio?"

Mrs. Dillon shook her head.

"I did not meet the men personally. My friend took me there and showed
me the picture."

"This same expert to whom you referred?"

"Yes."

"And yet you feel that his judgment was unbiased?"

"I do," Mrs. Dillon maintained loyally, "but I did not depend entirely
upon his opinion. I am a very good judge of pictures myself."

"Has it occurred to you that possibly you did not receive the same
painting which you purchased? I understand that sometimes art thieves
prey upon innocent buyers by showing them a genuine picture and then
delivering into their hands only a cheap copy."

"I am too shrewd to be so easily duped," Mrs. Dillon retorted. "I
don't mind telling you that I protected myself against j