, it reminded the boys of a sleeping whale.

On the top of it, amidships, was the conning tower, with thick glass
lenses for observation. From the conning tower also protruded the
periscope, an instrument which enabled the operators of the craft to see
the ocean about them even when submerged some twenty feet below the
surface.

A stout rail ran around the top of the hull so as to allow the crew to
walk along the slippery decks without danger of going overboard. But it
was the interior that the boys were most anxious to see, and a glad rush
followed when Mr. Barr invited them on board. Access to the conning
tower was gained by a gang plank running from the side of the shed.
Reaching the conning tower, with a press of eager lads about him, Mr.
Barr threw open a metal door in the top of the observation post, and
climbed inside. The boys needed no invitation to follow him.

Inside they found themselves in a compartment much resembling the
wheelhouse of an ordinary surface craft, except that there were various
instruments to show submergence, and the quality and pressure of the
air, and devices for handling the engines; for one of the features of
Mr. Barr's invention was that it could be handled by one man once the
engines were going.

Leaving the conning tower, they descended a steel ladder into the heart
of the submarine. The centre was occupied by a comfortably fitted-up
room which contained, among other things, a small library and a
phonograph. The inventor switched on a button and the "cabin," as it may
be called, was instantaneously flooded with a soft light, bright but not
glaring. In the bulkheads at either end of this compartment were doors,
steel riveted and solid looking. The inventor explained that beyond the
stern one were located the engine room and crew's quarters, while on the
other side of the forward portal lay the sleeping quarters, galley or
kitchen, and bathroom. Beyond these again came the torpedo room, which
contained the machinery for launching the death-dealers. Each of these
was inspected in turn, the boys being delighted with the compactness and
neatness of everything.

"Now," said the inventor, "we will visit the engine room." Paul Perkins
and Hiram looked interested; machinery was one of their hobbies.

The _Peacemaker_ carried two sets of engines, electrical for running
under the surface, and gasoline for use above water. The engines were
fitted tandem-wise, and to their shafts were attac