“Pump three hundred pounds into No. 1,” was the command given by Binns.  One of the levers was thrown over, and immediately could be heard the swirling of water.  The boys were unable to grasp the full meaning of what was going on until Bill Witt shuffled up and said:  “I’ll put you fellows wise to what’s going on, if you want me to.”

Ted and Jack were glad to know what it was all about and listened attentively to the commands of the navigating officer and the interpretations given by their new-found friend.  Bill explained that the process of diving was called “trimming” in submarine cruising, and that the pumping of the water being directed by Binns was done to fill the ballast tanks, thus increasing the displacement of the Dewey and causing it to settle in the water.  First one tank was filled, and then another, until the vessel was submerged on an even keel.  This was a revelation to the boys, for they had supposed it was only necessary to tilt the ship and dive just like a porpoise.

To their great delight the recruits found that the Dewey, like other submarines built since the beginning of the great world war, was equipped with twin periscopes, and that, furthermore, they would be allowed to watch the submersion of the Dewey through the reserve periscope if they so desired.  Would they care to?  Well, rather!  For the next few minutes they took turn about peering into the mirrors that reflected the whole panorama before their eyes.

Gradually, they could see, the Dewey was settling into the embrace of the sea.  Now she was down until the waves rolled completely over the deck and splashed against the conning tower.  Down, down they dropped till only the periscope projected above the waves.  Before them stretched the wide sweep of water, the ocean rising slowly but surely to overwhelm them.  One after another the waves surged by.  Now the eye of the periscope was so close to the crest of the water that it was only a matter of another moment until they would be under.  Up, up, up came the water to meet them.  Ted’s heart was in his mouth while he viewed this awesome spectacle.  Then he gave way for Jack to take a squint through the tube that carried with it a last look at the world of sunlight they were leaving.  And now the eye of the periscope was so near submersion that the swell of the waves swept over it and momentarily blotted out the light.  Then the spray dashed madly at the “eye” of the tube—–­and they were under!

Down in the depths of the ocean!  It was a moment to stir the pulses of the two Brighton recruits.  Wide-eyed in wonder, tense with the strain of the experience, they stepped back from the periscope.  Through Ted’s mind flitted memories of Jules Verne’s “Twenty Thousand Leagues Under the Sea,” and he was suddenly inspired to find out whether it was possible to glimpse any of the wonders depicted by the writer.  A peep into the tube showed only a greenish haze as the rays of the sun seemed trying to follow the Dewey into the depths.  Against the eye of the periscope streamed a faint flicker of greenish particles in the water that reminded the boy of myriad shooting stars.  And then—–­nothing but a blur of black!