"There were three attempts, each resulting in death. The skull is emblematic of death."

"Will you tell us why you tried to avoid Clifford, and were startled at the sight of the skulls?" asked John.

"If, as you say, you have found the copper box, I have no further reason to remain silent. I found one of the skulls,--the others I could not find, one of which I knew must be in the treasure cave. If I had known you found the one in the cave I should not have tried to get away, as I hoped, finally, to find the cave. Since coming here I learned that you had found the third island; I knew of only two, and supposed that the two skulls were from those two, namely, Wonder and Venture Islands."

"But who placed the skulls there?" queried Harry.

"Ah! No one knows that. The Spaniard Guiterez offers no explanation. All the so-called _treasure charts_ have been made from the accounts which he gave, of the vast amount of gold and silver which is hidden in these natural caches. The place where the copper box was deposited is the grand mausoleum. Only those who know the secret could ever reach the vault. All others would perish."

"The carbonic gas!" exclaimed George.

Walter turned to George, as he said this, but did not comprehend what he meant. It was now evident that Walter had tried to conceal his ident.i.ty, and thereby hide the secret which would enable him alone to find the vast wealth.

"So the letter which we found concealed in the seat of our boat, was written by one of your companions?" asked Harry.

"Yes."

"This clears up the mysterious things which we have tried to fathom for over two years," said John. "The meaning of the letters is now clear."

"From the time we landed on the island," rejoined the Professor, "we found evidences of white people that we could not follow up, and it is now plain that they were in search for the treasure, so we can now comprehend what the notes meant."

There is but little more to add to the chapter pertaining to the experiences of the boys on the islands. Perhaps, at some time in the future, their work on the new islands will be told. What John and the boys found in the Copper box, the historical sketches and the locations of the treasure islands which were pointed out on the parchments found in the compartment below the skull, were amazing revelations of the days of piratical adventures, when the southern half of the world was one vast carnival of crime, in which gold was the only booty and to obtain which the means were always considered to be justified by the end.

Our young friends, during their experiences in southern waters, did their part in bringing to the uneducated savages the blessings of civilization and the great boon of peace. To themselves they brought a store of hard-earned knowledge and a memory of things well done that will last them to the end of their days.

THE END

The Mountain Boys Series

1. PHIL BRADLEY'S MOUNTAIN BOYS

2. PHIL BRADLEY AT THE WHEEL

3. PHIL BRADLEY'S SHOOTING BOX

4. PHIL BRADLEY'S SNOW-SHOE TRAIL

These books describe with interesting detail the experiences of a party of boys among the mountain pines.

They teach the young reader how to protect himself against the elements, what to do and what to avoid, and above all to become self-reliant and manly.

THE HICKORY RIDGE BOY SCOUTS

A SERIES OF BOOKS FOR BOYS

By Capt. Alain Douglas, Scout-master

THE CAMPFIRES OF THE WOLF PATROL

Their first camping experience affords the scouts splendid opportunities to use their recently acquired knowledge in a practical way. Elmer Chenoweth, a lad from the northwest woods, astonishes everyone by his familiarity with camp life. A clean, wholesome story every boy should read.

WOODCRAFT; OR, HOW A PATROL LEADER MADE GOOD

This tale presents many stirring situations in which the boys are called upon to exercise ingenuity and unselfishness. A story filled with healthful excitement.

PATHFINDER; OR, THE MISSING TENDERFOOT

Some mysteries are cleared up in a most unexpected way, greatly to the credit of our young friends. A variety of incidents follow fast, one after the other.

FAST NINE; OR, A CHALLENGE FROM FAIRFIELD

They show the same team-work here as when in camp. The description of the final game with the team of a rival town, and the outcome thereof, form a stirring narrative. One of the best baseball stories of recent years.

GREAT HIKE; OR, THE PRIDE OF THE KHAKI TROOP

After weeks of preparation the scouts start out on their greatest undertaking. Their march takes them far from home, and the good-natured rivalry of the different patrols furnishes many interesting and amusing situations.

ENDURANCE TEST; OR, HOW CLEAR GRIT WON THE DAY

Few stories "get" us more than ill.u.s.trations of pluck in the face of apparent failure. Our heroes show the stuff they are made of and surprise their most ardent admirers. One of the best stories Captain Douglas has written.

UNDER CANVAS; OR, THE HUNT FOR THE CARTARET GHOST

It was hard to disbelieve the evidence of their eyes but the boys by the exercise of common-sense solved a mystery which had long puzzled older heads.

STORM-BOUND; OR, A VACATION AMONG THE SNOW DRIFTS

The boys start out on the wrong track, but their scout training comes to the rescue and their experience proves beneficial to all concerned.

BOY SCOUT NATURE LORE TO BE FOUND IN THE HICKORY RIDGE BOY SCOUT SERIES, ALL ILl.u.s.tRATED:--

Wild Animals of the United States--Tracking--Trees and Wild Flowers of the United States--Reptiles of the United States--Fishes of the United States--Insects of the United States and Birds of the United States.