“I am sure of it. At the time I welded it I did not know what it was. I took his word that he was an inventor, and this was some new kind of instrument. But now—”

“Now you think he was a burglar and robbed Mr. Lee’s store?” finished Dan with a smile.

“Yes, and more than that. I think he was the one who robbed the doctor’s house. He had some one with him, but I am sure he used a jimmy. Now we shall have to prove that the same person, or persons, who robbed the store robbed the doctor’s house.”

“How are you going to do it?”

“I think I can apply a few principles of common sense to this case, and it may result in getting some valuable information.”

“I hope it gets the robbers.”

“That is another matter; but it may. At any rate we shall know whether or not we are on the right track.”

“But I don’t see how you can tell whether the same person who broke into Mr. Lee’s store, also broke into the house of Dr. Maxwell.”

“I’ll show you pretty soon. I wish you would go to the old blacksmith shop, and get me the dividers I used to use. You will find them over the work bench.”

“I know where they are. I’ll get them.”