"I see—yes, I see—and I've got the data."

Jack had perceived that the old man was quite intelligent for his station in life, and having arranged to meet him at his home in Newark, Jack bade him good-day and returned to his lodgings.

CHAPTER IV.

A MOST WONDERFUL "SHADOW"—GOING OVER A RAILROAD DIARY—AN INCIDENT THAT WAS SUGGESTIVE—A MARVELOUS DISCOVERY—THE OLD TRUNK—ON THE TRACK OF A GENUINE CLUE.

Our readers may think it strange that the detective should go out of his way to listen to an old man's tales of a railroad, but Jack had become possessed of an idea. His idea may have been "far-fetched," as they say, but he believed he was building on a good logical basis; at any rate he was sufficiently prepossessed in favor of his theory to determine to make a fair test, and little did he dream how straight to the mark he was going. He resolved, however, to go ahead without knowing.

On the day following, at the time named, Jack appeared at the old man's house, and found Mr. Douglas glad to welcome him. The ten dollars and a prospect of more money made the man with the diary quite solicitous to furnish all the information he could.

"Let me see," said Jack, "when did you start the diary?"

"The very day I was first employed on the road."

"And you have kept it faithfully?"

"Yes, I have recorded every incident of importance as it occurred, even to the names of every conductor and official of the road."