THE SECRET OF THE HOLD
In response to Ned's hand on the lever, the water door closed and the
pumps in the next compartment soon cleared not only the sea vestibule
but the tanks of the submarine of seawater.
In a moment the Sea Lion lifted to the surface, and Ned lost no time
in relieving himself of his helmet. Then, still attired in the rubber
suit, he hastened to the conning tower, where he found Jack, glass in
hand, sweeping the moonlit sea eagerly. There was a faint haze off to
the west, but nothing more. Whatever had passed above the submerged
boat, on the surface, had wholly disappeared, though the time had been
very short.
"What did you see?"
Ned asked the question because Jack's manner indicated excitement, if
not anxiety.
"Just a shadow," was the reply.
"It might have been a shadow, passing over the moon, the shadow of a
cloud, or a cloud itself," suggested Frank, sticking his head out of
the hatchway.
Ned pointed to the sky. There was not a cloud in sight.
"It must have been something of the kind," Jack mused, "for no boat
could get out of sight so soon."
"Not even a submarine?" asked Ned.
"What do you mean by that?"
"Did you see a submarine?"
Both questions were asked in a breath.
"No," replied Ned, "I did not see a submarine, but I don't believe any
cloud passing over the sky would drop anything like this."
He passed the knife to Jack and took the glass. Jack opened his eyes
wide as he examined the weapon and noted the initial on the handle. He
turned impulsively to Ned.
"Where did you get it?" he asked.
"At the bottom."
"Did you find it lying there?"
"It fell just as I reached the water chamber."
"Then how the dickens did the Diver get away so soon?" demanded the
boy.
"It sure did fall from the Diver," agreed Frank, taking the knife and
examining it.
"It would seem so," Ned replied, "but, of course, the initial may be
merely a coincidence."
"I guess we're in for it."
"But how did the Diver get here so soon after our arrival?" asked one
of the boys.
Ned looked grave for a moment, and then replied, his manner showing
how fully he appreciated the importance of his words:
"What I fear is that she got here first."
"And found the wreck?"
"She might have done so."
"Did you see anything of the Cutaria down there?" asked Frank.
"Not a bloomin' thing," answered Jimmie, making his appearance on the
conning tower.
"The Diver might have towed it away," suggested Jack.
"Impossible!" cried the others, in chorus.
"Anyway," Jack continued, "we're up against the real goods now. If the
Diver is here we'll have a scrap."
"But suppose it should be some other outfit?" asked Frank. "Some
pirate outfit after the gold?"
"Still there would be a scrap."
"That's one advantage of goin' with Ned," Jimmie edged in. "You most
always get into a scrap!"
"Well," Ned said, presently, "we may as well drop down and keep our
lights low. If the Diver is here, the Moores are aware of our
presence, and we must be prepared for anything."
In ten minutes the submarine lay at the bottom of the sea, with no
lights showing, every plate glass window having been shuttered on the
outside by a system of protection which was one of the best features
of the craft. Then Ned explained that he had seen, at some distance,
an apparent elevation rising from the sand.
"That may be the wreck," he said.
"I move we go and see," shouted Jimmie.
"In the darkness?" asked Frank.
"It is as light out there now," Jack declared, "as it will ever be,
unless some subterranean volcano lights up and makes fireworks on the
bottom, so we may as well be off."
"All right," Ned said, in a moment. "I was meditating a little rest
to-night, but it may be advisable to get to work at once. For all we
know the Moores may be stripping the wreck, even now."
"What I can't understand," Jack said, sticking to the first
proposition, "is how the Diver got here in such good time."
"As has been said, it may be some other craft," Frank consoled.
"Don't believe it," insisted Jimmie. "The boat that dropped that knife
is a submarine, else how could she disappear so suddenly? She may be
watching us now."
"Or her divers may be prowling around the Sea Lion!" Jack created a
little sensation by saying.
"What would be the use of prowling around outside the boat?" asked
Jimmie. "They couldn't hear anything, or see anything."
"But a torpedo will act under water," suggested Frank. "Those chaps
are equal to anything."
"Shall we go out and look around?" asked Jack.
Ned hesitated. He really was alarmed at the situation. He knew how
desperate the Moores must be, and he had no doubt that in some strange
way the Diver had been brought to the scene of the wreck.
"If you and Frank are partial to a moonlight stroll under sixty feet
of water," he finally said, "you may as well put on your water suits
and look around."
"Leave Jimmie here to watch the boat and come with us," urged Jack.
"Go on," Jimmie advised. "I can run this shebang, all right. Go on and
see what you can see."
"If we are going out to-night," Ned said, after reflection, "we may as
well shift the Sea Lion and inspect the bottom over where we saw the
apparent elevation."
"Yes; that may be the wreck," Jack admitted.
So the submarine was moved a short distance to the north, about the
space which had seemed to separate the boys from the elevation, and
preparations were made for going out. Jimmie was rather pleased at the
idea of being left in charge of the submarine.
"Of course you'll not touch the machinery," Ned warned. "All you can
do is to see that the air pumps are kept going. Any motion of the
boat, you understand, might break or disarrange the hose carrying the
air to us, so be careful."
"Oh, I guess I don't want to murder any of you," laughed the little
fellow. "Go ahead and I'll run things all right on board the boat. I
could operate her anywhere."
The Sea Lion was lifted only a trifle in order to make the change to
the new location. As she moved along she was not much more than a
fathom from the level sand below.
This was done by regulating the water in the tanks to the pressure at
the depth it was desired to navigate. The delicate mechanisms designed
to show depth, pressure, air value, and all the important details of a
submarine were absolutely perfect.
So the three boys entered the water chamber, leaving Jimmie grinning
through the glass panel. When the boat was brought to the bottom they
opened the outer door and stepped out.
The Sea Lion had traversed only a short distance, yet the surface upon
which the lads walked seemed very different from the smooth sand level
Ned had seen before. There were now little ridges of sand, and now and
then a pit opened up almost under their feet.
A dozen yards from where they emerged from the submarine they came
upon the elevation which Ned had observed on his first trip out. It
was not, however, a submerged rock or a bit of harder soil in the
desert of sand. It was the hull of a wrecked vessel.
Ned moved along one side of the wreck, as far as his air-hose would
permit him to go, and was satisfied that he had found the lost mail
ship. The sand was already drifting against her sides, but she was
still far from buried.
On the port side, about a third of the way to the stern from the bow,
the boy discovered the wound which had brought the stately vessel to
her present position. She lay, tilted about a quarter, in eighty feet
of water.
Ned wondered why passing vessels had not discovered her. The tall
stacks had been beaten down, probably snapped off at the collision,
but the superstructure was high, and not far below the surface, Ned
thought.
After motioning Jack and Frank to remain at the break in the side of
the ship, Ned clambered up and, being careful to protect his air-hose
and line from the jagged edges of the wound, crept inside. His
electric flashlight revealed the interior only a short distance ahead
of him, but at the very outset he saw that some of the air-tight
compartments remained intact.
There was a lifting, swaying motion occasionally which told him that
there was still air imprisoned in the broken ship. At that distance
from the surface there would be no wave motion to produce the
oscillations he observed.
"It is very strange," he mused, as he clambered over bales, chests and
boxes in the hold, "that the ship should have gone down so quickly.
Telegraphic reports at the time of the accident--if it was an
accident--stated that she sank slowly. It would require only a little
assistance to bring her to the surface."
The boy made his way as far into the interior as he could with his
comparatively short air-hose, and then turned back to where he had
left Jack and Frank. He had found it impossible, on account of the
shifting to the prow of the hold cargo, to reach the cabin and the
captain's offices without entering from the top deck.
As he turned around he stopped an instant, his attention attracted by
a sound which seemed to come from beyond the bulkhead back of him. It
sounded almost like the hiss of escaping steam. The lad knew that it
must be a strong vibration which could thus make itself felt at that
distance below the surface and through the heavy helmet he wore.
The more he considered the matter the clearer became the fact that it
was actually uniform sound he heard. That is, sound brought to his
ears by the water.
Some force might be moving the water, and the motion might be
conveying to his ears, through the thin sides of the air-hose, the
story of the action of the waves, if waves could be created at that
depth.
As he listened to the steady beating he became convinced that some
unknown power was at work in the wreck. What it was he could not even
guess.
Then he heard sharper sounds which seemed to be created by steel
striking steel. The jar brought the sound waves to his ears quite
distinctly.
"Either I'm going daffy," the boy mused, "or there is some one at work
on the wreck."
He left the hold and, without giving the others to understand that he
had discovered anything of importance, began an examination of the
sand along the line of the bottom. His air-hose was not long enough to
admit of passing entirely around the vessel, so he motioned to the
boys to accompany him and turned back to the submarine.
"Did you hear anything down there?" asked he as soon as the helmets
had been removed.
"What are you talking about?" asked Frank, with a laugh. "Water would
not convey sound to the ear."
"But the jar of water would," observed Jack. "I heard a jar while I
was down there."
"I don't believe it!" Jimmie cut in.
"When in swimming," said Frank, "did you ever sit on the bottom of the
swimming hole and pound two stones together?"
"Of course," laughed the little fellow.
"And you heard a noise?"
"I believe I did, but it was not such a noise as one would hear from
the same cause in the air."
"Well," Ned went on, "I heard noises down there, too, and I'll tell
you right here that I'm alarmed."
"Scared!" roared Jimmie.
"Alarmed at what?" demanded Frank. "I didn't see anything to be
alarmed at."
"I have no theory as to what it was I heard," Ned went on, "but I'm
going to get a longer air-hose, shift the Sea Lion so she will hang
over the wreck, and go down again right away."
"I'm ready!" laughed Jack. "I want to hear that noise again."
"Do you think there are men down there removing the gold?" asked Jack.