Readers of the preceding volumes in this series are familiar with all
these people, now decidedly famous in the submarine boat world. In the
first volume, "_The Submarine Boys on Duty_," was related how all these
people came together; how the boys, by sheer force of character "broke
into" the submarine boating world. In that volume the building of the
first of the company's boats, the "Pollard" was described, and all the
exciting adventures that were connected with the event were fully
narrated.

Our former readers will also remember all the wonderful adventures and
the rollicking fun set forth in the second volume, under the title of
"_The Submarine Boys' Trial Trip_." In this book, bristling with
adventures, and made lighter, in spots, by accounts of humorous doings,
was told how the boys gained fame as submarine experts. It was their
fine, loyal work that interested the United States government in buying
that first boat, the "Pollard."

The third volume in the series, entitled "_The Submarine Boys and the
Middies_" told how our young friends secured the prize detail at
Annapolis; where, for a brief time, the three submarine boys served as
instructors in submarine work to the young midshipmen at the Naval
Academy. Nor was this accomplished without serious, and even sensational,
opposition from the representative of a rival submarine company. Hence
the boys went through some rousing adventures. Incidentally, they
fell against practical instruction in hazing at the Naval Academy.

Adventures enough had befallen the submarine boys to last any man for a
lifetime. Yet, as fate decreed it, Captain Jack Benson and his staunch
young comrades were now destined to adventures greater and further