"Here you are!" exclaimed Tom, as he switched out the lights in
the cabin. For a moment they were in darkness, and then, with a
click, steel plates, guarding heavy plate glass bull's-eyes,
moved back, and Mr. Hardley for the first time looked out on an
underwater scene. He saw the murky waters of river down which
they were proceeding to the bay moving past the glass windows.
Now and then a fish swam up, looking in, and, with a swirl of its
tail, shot away again, apparently frightened well-nigh to death.

"Bless my shoe laces, Tom!" exclaimed Mr. Damon, "this isn't a
marker compared to some of the sights we've seen, is it?"

"I can imagine not," said Mr. Hardley. "But it is interesting.
I shall be anticipating more wonderful sights."

"And you'll get them!" exclaimed Ned. "Do you remember, Tom,
the time the big octopus tried to hold us back?"

"Yes, indeed," answered the young inventor. "That gave us a
scare for the time being."

Steadily the M. N. 1 kept on her way under water. Her path was
illuminated to a considerable degree by a broad, diffused beam of
light from a powerful searchlight that was fixed just back of the
conning tower, giving the helmsman a certain degree of vision.
This light also served to illuminate the water, so that those in
the forward cabin could see what was going on around them.

"There isn't much of interest in the river," said Tom. "No big