Just before low water on the following morning, the salvage party set out for the wreck. As Mr. McKay had predicted, the weather was fine, there being no swell to speak of within the lagoon, though as usual the breakers were lashing themselves into milk-white foam upon the outer fringe of the reef.

Once more the slings were hove tight, and as the tide rose, the wrecked craft was again lifted from her ocean bed. Directly the yawl was "lively," as Ellerton expressed it, two more slings were pa.s.sed underneath her keel so as to make doubly sure of her being swung properly.

CHAPTER XXII

THE TREASURE CHAMBER

At high water the wrecked craft was moved for a distance of nearly a hundred yards towards the sh.o.r.e ere she grounded. This completed the day's work, and on the following morning at low tide the "slack" was again taken in so as to enable the rising tide again to lift the yawl clear of the bottom.

This time, owing to the bed of the lagoon shoaling more rapidly, only twenty yards were gained.

"It will be a tiring and tedious job, I can see," said Terence. "How are we to manage when the hull is brought close in sh.o.r.e?"

"We'll have to be content to move her a few feet at a time," replied Ellerton. "It's slow work, I admit, but we are making very satisfactory progress."

With the arrival of the neap tides, the work came to a standstill, the rise of water being insufficient to justify the time and labour spent on it; so the slings were cast off and buoyed, and the canoes brought into the little natural harbour, where they would be safe from all but an exceptional on-sh.o.r.e gale.

During the interval, the lads utilised several spare lengths of rails, and spiking them into rough sleepers, formed a temporary hauling-up slip.

Two of the wagons were dismantled, and the axles and wheels attached to a cradle, while a winch was firmly bolted to a secure foundation on the sh.o.r.e at twenty yards above high-water mark.

The rails were to be laid down at low water as far seaward as possible, and the sleepers sunk by means of heavy stones. Andy hoped to avail himself of a high spring tide to float the yawl right over the cradle, then, casting off the lashings that supported her, they could haul the wreck up by means of the winch and effect the repairs at their leisure.

Unfortunately, with the return of the spring tides a strong on-sh.o.r.e breeze sprang up and continued with unremitting freshness for over a week, so that the members of the salvage party were compelled temporarily to abandon their enterprise.

"Never say die," exclaimed Mr. McKay encouragingly. "Another fortnight and I hope we shall be able to resume the work. In the meantime, lads, what do you say to a kind of picnic?"

"A picnic?" asked Ellerton. "Where to?"

"I am thinking of paying another visit to the buccaneers' cave. I'm very curious to know what is on the other side of that iron-bound door, and I've no doubt you are equally so."

"Hurrah!" shouted the lads in chorus. "When shall we start?"

"In an hour," replied Mr. McKay promptly.

"Bursting open the door will be a tough job," remarked Andy. "How do you propose to do it?"

"I hope to manage it by means of an explosive," replied his father.

"Dynamite?"

"No, there's too much risk in carting a few sticks of that stuff through a tunnel a hundred yards in length or more. One slip and it would mean sudden death to the lot of us. I want a couple of fuses, however, so while we are getting ready you can run up to the magazine and obtain them."

While Andy was away on his errand, Mr. McKay opened a few cartridges and extracted the cordite.

"This stuff is safe enough with reasonable precautions," he remarked to Ellerton, who was watching Mr. McKay with no little fear. "So long as it is not under compression cordite can be lit without the faintest danger. In the open air it merely fizzles like a damp squib."

"Couldn't we smash the door with an axe?" asked Ellerton.

"We could, but I prefer not to. In the first place there's not much room to wield an axe; in the second, as I mentioned before, I have my suspicions regarding that door."

"What suspicions, sir?"

"Wait and see!" replied Mr. McKay with a laugh.

On the arrival of Andy with the fuses, the little party set out for the cave, each member carrying part of the equipment. On gaining the summit of the hill overlooking the house, Mr. McKay scanned the horizon with his gla.s.ses to satisfy himself that no canoes were approaching the island, then, having rea.s.sured himself on that point, he gave the word to step out briskly.

"I don't want to spend a night away from the house in case anything happens," he explained.

"But do you expect another crowd of savages?"

"I didn't expect the last lot," he replied grimly, "but they came all the same."

The journey through the forest and across the rock-strewn plain was performed without incident, and within a couple of hours after leaving the house the party drew up at the mouth of the tunnel.

Here each member lit a lantern, and in a comparatively bright light the pa.s.sage of the tunnel commenced. Quexo, however, remained in the open air. Nothing could prevail upon him to descend into the bowels of the earth.

Once or twice someone stumbled, Terence falling heavily and barking his shins, while Mr. McKay's head came in contact with the roof much too often for his liking; but in high spirits the explorers crossed the floor of the abyss, traversed the second tunnel, and gained the armoury. Here they rested ere commencing the final stage of their journey underground.

At length the explorers came face to face with the mysterious iron-bound door. In spite of themselves they felt a strange sensation as they gazed upon the relic of bygone days. What lay behind it? What secret did it guard so well?

"Stand back a bit, lads, and hand me another lantern," said Mr. McKay.

Dropping on his knees, he carefully examined the floor and the iron-shod threshold of the door, probing the narrow slit with his knife. This done, he turned his attention to the walk and the crown of the arch next to the woodwork, tapping the stone with the blade of his knife with the greatest caution.

The others looked on with interest not unmingled with curiosity and awe. At length, apparently satisfied with the examination, Mr. McKay rose.

"I want you to bore a hole here," said he to Andy, pointing out a place in the door barely two inches from the floor.

Andy, armed with a ratchet-brace, began his task, and the subdued silence of the underground pa.s.sage was broken only by the rattle of the pawl and the sharp burr of the bit as it wormed its way steadily through the stout oaken plank.

"It's hot work," exclaimed Andy, who in order to use the brace in that most inconvenient place was obliged to lie full length on the floor.

"I know, but keep it up," replied Mr. McKay, who, grasping a crowbar, was standing astride his son's feet.

"Stand a bit farther back," he continued, addressing Ellerton and Terence.

The two lads instantly obeyed, though they wondered at Mr. McKay's alert and expectant att.i.tude.

Suddenly, like the tongue of an enormous serpent, a double-p.r.o.nged barb of steel flashed dully in the candle-light, pa.s.sing completely across the pa.s.sage and about three feet above and over Andy's prostrate body.

In an instant Mr. McKay's powerful arm brought the crowbar upward in a resistless sweep, and with one blow severed the dreadful device of death.

The lads, pale with the excitement and horror of the incident, could only utter an exclamation of astonishment while Andy hurriedly backed away from the well-guarded door.

"Pleasant, isn't it?" remarked Mr. McKay in a cool matter-of-fact tone, as if such incidents were of an everyday occurrence. "I had my suspicions, as I said more than once before. That device was cunningly contrived to salute marauders in a very forcible manner. Had either of us been standing in front of the door we should have been transfixed in a jiffy. Now, carry on, Andy. I don't think there's anything more to be feared on this side of the door, at any rate."