THE TUNNEL ENTRANCE.
The tender was a light one. It was no very hard task for the party to
draw the little craft up the beach and into the concealment of a clump
of bushes.
Hardly had this been done, when around the point behind which they had
landed, came the craft they had heard. The night was starlit, and in the
dim radiance they could see her dark outlines coming on at a good speed.
Beyond the little cove into which they had drawn the tender was a fairly
high cliff, rocky and threatening. The motor boat crossed the little
cove and kept straight on. No lights burned on her. Plainly her errand
was not one which those on board cared to advertise.
“Great Scott! what is she going to do?” exclaimed the inspector, in a
low whisper, as the motor boat kept right on across the little cove
without altering her course in the least. Not one degree did she swerve
from the route she was steering.
“What on earth do they mean to do?” breathed Ralph. “Run the boat smack
into that cliff?”
“Looks as if they are bent on suicide,” commented Jennings uneasily.
“I told you it wasn’t any ordinary kind of boat,” said Harry Ware. “It
wouldn’t surprise me if——”
“Jumping Jupiter!” burst from the inspector.
The rest of the party could only gasp their amazement. At the moment
articulate speech was impossible.
The motor boat had reached the cliff—and vanished without sound or sign.
“She’s gone down!” cried Ralph, the first to recover from his
astonishment.
“Gone down, nothing!” retorted Harry scornfully. “She’s just melted into
air, that’s what.”
“Don’t be so foolish,” chided Inspector Jennings. “Depend upon it, that
is another of their tricks, like the ones they played on you, boys.”
“We’ll start for that cliff and examine it,” declared the chief
inspector. “There’s some clever sleight of hand in all this mummery.”
“We’re going to that cliff!” gasped Harry, in affrighted tones.
Nevertheless he set off with the others, but he might have been observed
to hang some distance behind them. The boy was now more firmly convinced
than ever that there was something supernatural about the mysterious
craft.
“The Fenians had all sorts of secret ways of landing upon and leaving
this island,” said the chief inspector; “and I’ll wager that the motor
boat just used one of those to work the trick we’ve just seen.”
The night was warm and there were occasional flashes of summer
lightning. To Harry’s thinking, this made the strange quest they were
engaged on all the more uncanny.
At last they reached the cliff.
“I wish another flash would come,” said Ralph, “we daren’t light
matches. But I brought along an electric torch.”
“A good idea. We may need it later,” said the inspector. “Hullo! Look
there! I guess that explains the mystery of the motor boat’s vanishing.”
Another flash had revealed a tunnel-like hole in the cliff which could
hardly be observed from the water side, on account of several thick
bushes which grew, either by accident or design, about its mouth.
“There’s a path,” said Ralph presently, as another flicker of lightning
revealed a rough trail leading up the cliff face.
“We’ll follow it. Easy, now, boys, we don’t want to give the alarm,”
warned the chief inspector.
Through the darkness the intruders on the gem smugglers’ realm crept up
the slippery track. At last they gained the top. Below them, as the
flickering flashes showed, was a big pool of water, either natural or
artificial. Doubtless the tunnel through the cliff led into it, for
moored to one side of the pool could be seen the mysterious motor boat.
There were no lights on board her. Apparently those who had arrived at
the island had made their way up the hill to the windmill tower, for a
light could now be seen gleaming, like an angry eye, half-way up the
structure.
“They’re all up there. Collecting their effects preparatory to leaving
the island forever, I imagine,” whispered the inspector. “Let’s have a
look at their boat.”
It was a rather risky business, but still they were a strong party and
the government officers were well armed. The descent to the side of the
pool was made by a rocky path very like the one by which they had
ascended the cliff.
Harry hung back while the others inspected the boat. But Ralph rallied
him after a short time.
“She’s all solid, Harry,” he declared; “come on and see for yourself.
Nothing ghostly about this fellow, unless a sixty horse-power motor of
the best and speediest design appeals to you as being spookish.”
Harry came forward and soon satisfied himself that it was all as Ralph
had said. Inside the boat they found tubs of phosphorus, for producing
the ghostly effect that had so scared Harry, plenty of spare lanterns to
work the stern-light trick and a stern search-light of great power,
evidently intended to be thrown full in the eyes of the helmsman of any
pursuing craft and dazzle his vision.
In a locker, too, were sheets with holes for heads and a number of masks
painted to resemble grinning skulls.
“Quite a paraphernalia,” grinned the chief inspector. “All this would
make a regular eight-hour-union ghost turn green with envy.”
In a small shanty which stood close by they found more evidence to show
how the operators of the _Artful Dodger_ had been practicing on the
credulity of the islanders. All sorts of rigs and canvas frames by which
the outlines of the motor boat might be altered at will were discovered.
For instance, one frame was found which could be hooped on to the boat’s
stern, changing her whole appearance. A false cabin top was also found,
by means of which the _Artful Dodger_ could be speedily converted to a
cabin cruiser, in case any one was looking for a motor boat of another
type.
“Well, this is the most complete layout we have uncovered for some
time,” spoke the chief inspector. “I think——”
But Ralph interrupted him.