n 1887, had published an
important book on the subject of double propulsion in submarines.
Though Holland had made many improvements on these earlier theories,
he soon found out that even at that there was going to be serious
trouble with the _Plunger's_ engines. The boat had been launched in
1897; but instead of finishing it, he persuaded the government to
permit his company to build a new boat, and to return to the
government all the money so far expended on the _Plunger_.

The new boat, _Holland No. 8_, was started immediately and completed
in record time but she, too, was unsatisfactory to the inventor. So
without loss of time he went ahead and built another boat, the
_Holland No. 9_, which, as we have said, became the first United
States submarine.

Two other men submitted plans for submarine boats in the competition
which was won by the Holland boat, George C. Baker and Simon Lake.
Neither of these was accepted. Mr. Baker made no further efforts to
find out if his plans would result in a practicable submarine boat.
But Simon Lake was not so easily discouraged.

It is very interesting that the United States Navy Department at
that time demanded that plans submitted for this competition should
meet the following specifications:

1. Safety.
2. Facility and certainty of action when submerged.
3. Speed when running on the surface.
4. Speed when submerged.
5. Endurance, both submerged and on the surface.
6. Stability.
7. Visibility of object to be attacked.

In spite of the many years that have passed since this competition
and in spite of the tremendous progress that has been made in
submarine construction these are still the essential requirements
necessary to make a successful submarine boat.

The designs submitted by Mr. Lake provided for a twin-screw vessel,
80 feet long, 10 feet beam, and 115 tons displacement, with 400
horse-power steam engines for surface propulsion and 70 horse-power
motors for submerged work. The boat was to have a double hull, the
spaces between the inner and the outer hulls forming water ballast
tanks. There were to be four torpedo tubes, two forward and two aft.

In an article published in 1915 in _International Marine
Engineering_, Mr. Lake says about his 1893 design:

The new and novel feature which attracted the most attention and
skepticism regarding this design was (the author was later
informed by a member of the board) the claim made that the