Bidding his prisoners remain where they were, Diego crossed the hall and knocked at a closed door.

"Come in," called a man's voice, and Diego disappeared into the room, closing the door behind him.

Bill started to make some comment on their surroundings to his father, but their other guard growled at him to keep quiet. Then Diego reappeared and beckoned them into the room.

This large apartment was handsomely furnished in the manner of a business office. Behind a huge, flat-topped desk sat a fat young man dressed in immaculate white linens. Blue-black hair and an olive complexion bespoke his Latin origin. Two other young men, clad also in white, and bearing a strong resemblance to the man at the desk, lounged in wicker arm chairs. All were smoking long black cigars.

"And what, may I ask, is the reason for this outrage?" began Mr. Bolton, walking up to the desk. "Is it your custom to have visitors to this island treated like criminals and thrown into jail?"

"It is," the fat man remarked blandly, without removing the cigar from his lips.

Bill's father was taken aback by this unadulterated candor, but neither by manner nor change of tone did he betray his surprise. "How much do you want to let us go?"

The man at the desk knocked the ash from his cigar.

"Why, it's not a question of money at the present moment, Mr. Bolton.

That will undoubtedly come later. Just now, my brothers and I have need of you in other ways."

"You mean that we are to be kept here as your prisoners?"

"You have guessed the secret, Mr. Bolton. And my advice to you and to your son is to do exactly as you are told, without argument or question.

Strangers on Sh.e.l.l Island have always found that to disobey commands here is a particularly unhealthy pastime. Obey on the jump-is our slogan. I hope for your sakes that neither of you forgets it." He smiled at them affably and puffed on his cigar.

Mr. Bolton was about to speak his mind when Bill caught his arm. "Stow it, Dad," he said. "That lad has us just where he wants us. I'd like to say what I think, too,-but what's the use?"

Their host waved his hand and their guards led the Boltons out of the house.

Once on the road, tramping back toward the settlement below, Mr. Bolton pa.s.sed his arm through Bill's.

"Your Naval Academy training has put a head on your shoulders, son," he said affectionately. "You have developed better control of your temper under stress than I have. I'm glad you stopped me. Ordinarily a man of my position in the world is in the habit of speaking his mind when provoked."

Bill nodded. "One of these days," he said grimly, "I'm going to get that fat slob in there-and when I do, there won't be enough left of him for the state to burn. What's his game? Have you any idea?"

Mr. Bolton shook his head. "Not the slightest glimmer. It doesn't appear to be a case of ransom-or at least, not just yet. Whatever he is up to is obviously illegal. But we'll probably learn about it before long. The man is an educated criminal. His actions prove it. Our position is certainly serious-very serious."

"I vote we make a stab at getting out of that cell tonight," suggested Bill. "If I can get hold of our bus or one of the other amphibians, we'll get clear of Sh.e.l.l Island in short order."

"We'll spend the day thinking up a plan of operations," agreed his father.

As they came into the settlement, Diego tapped Bill on the shoulder.

"Come along with me, guy," he ordered. "Not you-" he snarled at Mr.

Bolton as he started to turn out of the road with his son. "Back to the lockup for yours!"

"Good bye, Dad, and good luck," Bill called as Diego's partner herded his father down the road.

"Good luck, and keep a brave heart," answered Mr. Bolton.

He called out something else, but Bill could not catch the words, for Diego had him by the arm and forced him through the doorway of the barracks before which they had been standing.

He found himself in a large room where thirty or forty men quite as villainous-looking as his guard were lounging about, smoking, sleeping or playing cards. Diego hurried him through this apartment, and down a bare hallway to the open door of a small room. Bill saw that except for an unpainted table and a chair of the kitchen variety, the place was empty of furniture. Over the chair a coa.r.s.e cotton shirt and a pair of cotton trousers were draped. Leg-irons and a pair of handcuffs lay on the table.

"Strip!" Diego pointed to the chair. "Them's your clothes, guy. Get into 'em."

"How about wearing my own?" Bill was fast losing his temper. Only the rifle which Diego held pointed in his direction prevented him from sending a right hand jab to the point of the thug's chin and taking his chance with the others in the room beyond.

"Nuttin' doin', bo-" snarled Diego. "Dem's de boss's orders. Make it snappy. We gotta get out o' here right away an' I want to pin de jewelry on yer."

"Where are we going?"

"I ain't goin' nowhere-but you are-" He grinned evilly at the lad-"youse is goin' ter be took fer a ride."

CHAPTER IV-THE INVITATION

Diego gave vent to a raucous laugh after making this announcement. He walked across the room, leaned his rifle against the table, and picking up the handcuffs inspected them critically. His prisoner was unarmed and too far away to offer an a.s.sault before he could s.n.a.t.c.h up his gun again. He did not fear Bill physically. But many people misjudged that slender body with the broad shoulders. The young midshipman was not yet seventeen; nevertheless he was star right end on the Navy team and as strong as a steel bridge. Now he saw his chance and took it.

Bending down as though to untie the pair of rubber soled sneakers he wore, Bill suddenly half straightened and his lithe form shot through the air. Before Diego could drop the handcuffs, one hundred and sixty pounds of bone and muscle struck him just above the knees and he crashed over backward beneath a perfect tackle. The unexpected jar and shock half-stunned him and before he could gather his faculties, Bill's fist, backed by the venom of a sorely tried temper smashed him behind his left ear. All lights went out for Diego, gangster and gunman, right there.

Bill scrambled to his feet, ran to the open door and peered out. The corridor was empty. He closed and bolted the door and after a moment's thought, he approached the unconscious gangster.

Five minutes later, a young man clad in cotton undershirt, ragged cotton trousers and rubber soled sneakers stepped through an open window on to the wide veranda which ran along the side of the barracks. On the young man's head was a floppy broadbrimmed hat of straw. He carried a rifle.

The owner of these articles lay on the floor behind the window, quite oblivious. When he came to again, he would find his wrists manacled behind his back, his right leg chained to the table, and a gag in his mouth. As Bill Bolton walked swiftly along the veranda, he conjured up the pleasing picture of Diego's awakening, and grinned.

With the hat's brim pulled well down and acting as a partial screen to his features, he ran down the broad wooden steps and out to the road.

Not a soul was in sight. Then suddenly his heart missed a beat.

"Hey, you! Where you goin'?" called a voice from the porch behind him, and a man he had not seen before ran down the steps. Just then a large handbell was rung somewhere within the building.

"Come in and get yer chow," called the man.

Bill felt that he would certainly cause suspicion if he refused to obey this suggestion. Moreover, he was thirsty and half famished. So he walked back to the steps.

"I reckon you're one of the new hands on the yacht," observed the man.

"That's right," admitted Bill.

"Thought so, when I seen yer beatin' down toward the harbor just afore dinner time. The boss feeds us swell here. Has to, with this gang to look after. Men get easy discontented in a sweatbox like this here island. How's the grub aboard the _Pelican_?. Useter be pretty bad."

"I've eaten worse," said Bill.

"Well, come along in and feed here today," turning back up the steps with him. "It's a hot walk along that sh.e.l.l road, and I'll need yer to help herd some of them prisoners down there later on."

Bill followed him into the building. This time he found the large room deserted, and pa.s.sing through a doorway to the right, the two entered a big hall, down the middle of which ran two long, narrow tables.

The men were already seated at dinner, and n.o.body paid the slightest attention to the new arrivals. Bill's companion took his place at the head of a table and motioned the lad to a vacant seat just below. A pitcher of what proved to be lemonade was within Bill's reach. He filled and emptied his gla.s.s three times before he began to feel refreshed. A slatternly negress placed a plate piled high with fried chicken, rice and fried plantains before him and he dug into it with the relish of a starved man.