Prebbles went back and picked up the letter. He was still greatly shaken, although he was getting firmer hold of himself by swift degrees.

It was a very ordinary appearing letter to have aroused such an extraordinary state of mind in the old man. The address, in a peculiar backhand, was to "Mr. Amos Murgatroyd, Loan Broker, Jamestown, North Dakota."

Prebbles was Murgatroyd's clerk, and the only clerk in the loan office. For several weeks Murgatroyd had not been in Jamestown, and the work of the office—what little there was—fell to Prebbles.

During those weeks of absence, the broker had been doing unlawful things. Prebbles, knowing his employer well, expected nothing better of him; but just what Murgatroyd had been doing, the old clerk did not know.

Strange men, who might be detectives in disguise, were watching the office night and day. Prebbles had been keen enough to discover that.

It was the peculiar handwriting of the letter that had had such a powerful effect upon the old clerk. Not one man in a thousand, perhaps in ten thousand, used a pen as the writer of that letter to the broker had used it. Prebbles felt sure that he could not be mistaken—that there was not the least possibility of a mistake. He knew who the writer of the letter was, and for weeks the old man's dream by day and night was that he could discover the whereabouts of the man.

The envelope was postmarked at Steele, N. D. The writer might be there, or he might not be there. After setting hand to the letter, it was more than possible he had mailed the letter at Steele and then gone to some other place.

There was one way to make sure—and only one: In order to find out positively where the writer of the letter was, Prebbles would have to open it and read it. Although a clerk in the office, his position did not give him the right to open his employer's personal mail; in fact, Murgatroyd had expressly forbidden this.

The letters received during Murgatroyd's absence—and they were but few—had been placed in the office safe. A week before, the collected letters had mysteriously vanished during the night, and in their place was left this scribbled line: