Thus Ruth and Alice questioned their friend, as he stood at the open window of the taxicab, looking at the crumpled paper.

"I—I don't understand it all," he confessed. "After I knew those fellows were after my patent I cautioned Mr. Burton about letting any strangers see it."

A figure came into the doorway of the machine shop. It was that of an elderly man, with steel-rimmed spectacles. His face was grimy with the dirt of metal.

"I'm awfully sorry, Russ," he said, contritely. "But of course I thought the note was from you, and gave up the model."

"Did Simp Wolley get it?" asked Alice, eagerly.

"No, a uniformed messenger boy came for it," explained Russ. "That was it; wasn't it, Mr. Burton?"

"Yes. And I had no suspicions. You know you had said you might want the model some time in a hurry, to demonstrate to possible buyers, and of course when the boy came with the note I supposed you had sent him. I'm not familiar enough with your handwriting to know it," he added.

"No, I suppose not," admitted Russ. "And yet if you had been this might have deceived you. It is very like my writing. I guess Wolley must have had a sample to practice on."

"It all seemed regular," went on Mr. Burton. "I was working away, making some of the finished appliances from your model and drawings, when the boy brought the note. He was a regular messenger boy, I could tell that. And the note only asked for the model—not for any of the finished machines, of which I had two. He didn't even want the drawings, or I might have been suspicious."

"They won't need the drawings as long as they have the model. They can make drawings themselves," spoke Russ.