Some time later, just as the town clock finished booming the hour of midnight, the officer touched the arm of his companion, who said,—­

“I haven’t noticed anything; what is it?”

“Did you hear some one walk past?”

“Yes; the footfall sounded plainly enough:  what of it?”

“That is the third time that man has gone by.  He is on the alert.”

“It may have been different persons.”

“It was the same man—­sh! there he comes on the porch.”

In the stillness of the night the sound was plainly heard.  The next moment a key turned in the lock of the door, which was silently shoved inward.

The visitor, whoever he was, acted with the coolness of a professional.  He entered by the main door, so, if it chanced that any one saw him, he could explain the cause of his visit.  At the same time, he made as sure as was possible that no one did see him.  Knowing the movements of the watchman, he waited until he was out of the way, with the certainty that he would not be back again under a half-hour at the least.  That interval was more than sufficient to do all that he had in mind, and to take his departure.

He opened the door so quietly that, but for the warning rattle of the key, it would have been hard for the watchers to hear him.  Almost before they knew it he stood inside with the door closed.  Here the light fell upon him, and revealed his identity to the men at the rear.

Neither was surprised.  Although they had not mentioned their suspicions to each other, both were morally certain the thief would prove to be the man whom they now identified.  G. Field Catherwood.

Walking quickly and softly across the floor to the private office, which opened off from the other end of the counter, the prospective partner of the business stooped down, turned the shining knob of the safe round until the right combination had been struck, and swung back the immense, massive door.  Then from an inner drawer he drew the merchant’s bank-book, in which were clasped several hundred dollars in bills.  Two of the largest denomination—­fifty each—­were withdrawn, and the book returned to its place.

No veteran could have been cooler than Catherwood.  He looked and acted no more like the exquisite on the steamboat than did Tom Gordon himself.  He was the sleek, cunning, hypocritical villain he had always been, stealing, not because he was in need of money, but because it was his nature to do so.

“Well, Mr. Catherwood, it looks as if the account will be a little short to-morrow!”

The miscreant started as if he had heard the warning of a rattlesnake at his feet.  Turning like a flash, he saw Mr. Warmore standing at his elbow.  Had he received but a few seconds’ notice, he might have tried to bluff it out, by pretending he had come to look after some matters about which he was not fully satisfied.  Holding the situation he did in the establishment, he could feel certain no one would suspect him of any sinister purpose.