He began with the paper bearing date June 19, and examined that and the succeeding papers with great care.  At length his search was rewarded.  In the paper for June 23 Luke discovered the name of James Harding, and, what was a little singular, he was registered at the Ottawa House.

Luke felt quite exultant at this discovery.  It might not lead to anything, to be sure, but still it was an encouragement, and seemed to augur well for his ultimate success.

He went with his discovery to his friend the clerk.

“Were you here in June, 1879, Mr. Lawrence?” he asked.

“Yes.  I came here in April of that year.”

“Of course, you could hardly be expected to remember a casual guest?”

“I am afraid not.  What is his name?”

“James Harding.”

“James Harding!  Yes, I do remember him, and for a very good reason.  He took a very severe cold on the way from New York, and he lay here in the hotel sick for two weeks.  He was an elderly man, about fifty-five, I should suppose.”

“That answers to the description given me.  Do you know where he went to from here?”

“There you have me.  I can’t give you any information on that point.”

Luke began to think that his discovery would lead to nothing.

“Stay, though,” said the clerk, after a moment’s thought.  “I remember picking up a small diary in Mr. Harding’s room after he left us.  I didn’t think it of sufficient value to forward to him, nor indeed did I know exactly where to send.”

“Can you show me the diary?” asked Luke, hopefully.

“Yes.  I have it upstairs in my chamber.  Wait five minutes and I will get it for you.”

A little later a small, black-covered diary was put in Luke’s hand.  He opened it eagerly, and began to examine the items jotted down.  It appeared partly to note down daily expenses, but on alternate pages there were occasional memorandums.  About the fifteenth of May appeared this sentence:  “I have reason to think that my sister, Mrs. Ellen Ransom, is now living in Franklin, Minnesota.  She is probably in poor circumstances, her husband having died in poverty a year since.  We two are all that is left of a once large family, and now that I am shortly to retire from business with a modest competence, I feel it will be alike my duty and my pleasure to join her, and do what I can to make her comfortable.  She has a boy who must now be about twelve years old.”

“Come,” said Luke, triumphantly, “I am making progress decidedly.  My first step will be to go to Franklin, Minnesota, and look up Mr. Harding and his sister.  After all, I ought to be grateful to Mr. Coleman, notwithstanding his attempt to rob me.  But for him I should never have come to the Ottawa House, and thus I should have lost an important clue.”

Luke sat down immediately and wrote to Mr. Armstrong, detailing the discovery he had made—­a letter which pleased his employer, and led him to conclude that he had made a good choice in selecting Luke for this confidential mission.