that."

"Martin?"

"Watson, I mean," corrected Mrs. Scarlet. "I sometimes call the boy
Martin, which is his middle name, so he has a right to it."

"Exactly. You KNOW that the boy had nothing to do with the robbery
last night. I don't wish to argue or dispute with a lady, but I shall
be compelled to question HOW you know so much. Will you answer?"

"Because--because Martin is incapable of such work. I have read all
about it in the papers, and am confident that it was the work of an
organized band." The Professor laughed until his white teeth gleamed
in the lamplight.

"So sure!" he said. "You consider that nephew of yours a pattern of
propriety. Is this the only reason you have for believing that Watson
Wilks had no hand in the murder of Arnold Nicholson, and the rifling
of the express company's safe?"

"I have another!"

"Well?"

"He was in Chicago at the time the deed was done."

"Can you prove this?"

Professor Ruggles seemed extremely eager, as he bent forward and