“At once, and with all diligence,” nodded the lieutenant commander.

Though a very thorough search was made, Sam Truax was not found.  It was thought, at the time, that the fellow must have been drowned.  Months, afterward, however, it was learned that he was skulking in Europe with Tip Gaynor, who had received word in time to make his escape also.

It may be said, in passing, that neither Mr. Farnum nor Mr. Pollard felt it necessary to go to the trouble of trying to have the scoundrels arrested and extradited to this country, and in this Jack Benson agreed.  Both rascals were rather certain, thereafter, to give the United States a wide berth.

For some time David Pollard had been holding aloof and keeping very quiet—­a habit of his, often displayed for long periods.  About this time, however, Mr. Pollard returned, with a triumphant twinkle in his eyes.  He had been hard at work upon, and had perfected, an improved device for the discharge of torpedoes through the bow tube of the Pollard submarine boat.

It is to be mentioned, also, that the Sidenham Submarine Company, while admitting that Gaynor had been entrusted with the sale of their boats to the Government, disclaimed all knowledge of the methods that salesman had been employing.  Everyone believed the disclaimer of the Sidenham concern, yet up to date none of its boats have been sold to the United States Government.

For two days more the submarine boat instruction continued at sea.  Then, the tour of instruction over, the little flotilla returned to the Naval Academy at Annapolis.  From here Captain Jack Benson wired Mr. Farnum for further orders.  Without delay back came the despatch: 

“Navy Department requests that, for present, ‘Farnum’ be left at Annapolis.  You and your crew will return by rail when ready.”

Soon afterward Jack was informed that the Annapolis police had succeeded in running down the mulatto who had decoyed the young submarine skipper on that memorable night.  Also, Jack’s money, watch and other valuables were recovered and returned to him.  The mulatto is now serving a long term in jail.  It afterwards turned out that nearly two-score seafaring men had been robbed by the mulatto by the same game that had been played on Jack Benson.

One forenoon when Jack, and his mates were about to go ashore, for good, from the “Farnum,” Lieutenant Commander Mayhew came on board, followed by Ensign Trahern and three of the midshipmen who had been under submarine instruction.

“Now, Mr. Benson, and gentlemen,” smiled Mr. Mayhew, “I’m not going to frighten you by making any set speech.  What I have to say is that the cadet midshipmen who have been under your very capable and much-prized instruction of late, wish each of you to take away a very slight memento of your stay here.  There is one for each of you.”

Not even Machinist Williamson had been omitted.  Each of the four received from the lieutenant commander a small box.  Each box, on being opened, proved to contain a small gold shield.  In the center was the coat-of-arms of the United States Naval Academy.  At the top of each pin was the name of the one to whom it was given.  Across the bottom of each pin were inscribed the words: