For the first few days of their stay in Nassau the boys found plenty to amuse them. They rowed out in a bright-hued rowboat with a glass set in the bottom and gazed at the famed “sea gardens” and found them even more wonderful than the ship’s purser had described. They clambered over the ancient forts Williams and George; they bathed, swam and fished to their hearts’ content and they visited the sponge docks where the speedy little schooners and sloops with their grinning black crews brought their catch of sponges to barter and trade.

The huge turtles, lying on their backs upon the decks of fishing boats, were a novelty to the boys and they were absolutely fascinated by the rainbow-tinted fish that swarmed in the waters and were sold in the market. And they learned many new and interesting things also. They had seen the bleached white corals in museums and saw the same everywhere for sale in Nassau; and the first time they visited the sea gardens and gazed down through the crystal clear water they were surprised that no corals were visible.

There were huge sea-fans—purple and golden brown, long, black sea-rods, brown and purple sea plumes, huge dull-orange and maroon starfish, innumerable sea anemones with immensely long and bright-colored tentacles and everywhere red, pink, yellow, blue and particolored fish, like some sort of exotic butterflies, flitting lazily among the marine growths. But not a white coral was visible. Great rounded mounds of orange, bits of scarlet, masses of green and lavender, of old rose and soft fawn brown were cluttered upon the bottom, but in vain the boys sought for the massive brain corals and graceful branched corals they knew so well.

“Well I don’t see any corals,” declared Tom after he had gazed at the multicolored objects upon the ocean bottom for some time. “It’s pretty, but I thought corals grew everywhere down here.”

The black boatmen chuckled. “Beggin’ yo’ pardon, Chief,” he remarked, “tha’s plenty coral down tha’, Chief. Yaas, sir, all erbout. Doan’ yo’ di’sarn ’em, Chief?”

“No,” replied Tom, “I can’t see a single white thing there—all I see are bright colored weeds and sea-fans and rocks.”

The negro looked genuinely surprised. “Bless yo’ soul!” he exclaimed. “Yo’ cawnt be a s’archin’ fo’ white coral is yo’? White coral’s jus’ dead coral, Chief. Tha’s da culmination o’ tha’ manner o’ it’s prep’ration, Chief. Yaas, sir, all tha’ objec’s yo’ di’sarn growin’ down to tha’ bottom is corals, Chief. Yaas, sir, some of tha’ kin’s is yellow an’ some red an’ some green.”

It was the boys’ turn to be surprised. “Why, you don’t mean all those things like stones covered with bright-colored weeds are coral!” exclaimed Frank incredulously.

“Yaas, sir, Chief,” the negro assured him. “Ah’ll demonstrate it to yo’ entire satisfaction, Chief.”

As he spoke, the half-naked negro stood up in the little craft and before the astonished boys realized what he was about to do he had plunged into the clear water and the boys watched in wonder as they saw him swimming easily straight towards the bottom, a little string of bubbles rising from him and the pink soles of his feet flashing strangely. In an instant he had reached the masses of growth on the sea floor and the boys saw him pulling and working at a projecting ledge of vivid violet and green. Then he turned and shot up to the surface like a flash. As he broke through the water he tossed a large lump of brilliant material into the boat and clambered over the stern.

Interestedly the boys examined what he had brought and to their absolute amazement discovered that it really was coral, but as the man explained, completely concealed under the fleshy covering of the animals which resembled tiny sea anemones of wonderful tints.

But after their first momentary surprise and interest at the discovery the two boys found much more to attract them in the denizens of the mass of coral than in the coral itself. Odd red and white crabs emerged from their hiding places, a tiny fish that glittered with the dazzling hues of a fire opal flapped from under a bit of adhering seaweed, funny slug-like molluscs of intense blue and gold crawled about the mass, queer little snails were everywhere and when the boys disturbed the coral or handled it they heard odd snapping noises like lilliputian firecrackers.

For a time this puzzled them until Frank discovered to his intense delight that the sounds were made by tiny lobster-like crustaceans that dwelt in holes in the hard coral and viciously snapped their claws when disturbed.

“Say,” asked Tom presently, “weren’t you afraid of a devil fish—octopus, you know—down there?”

“Bless your soul, no, Chief!” grinned the negro. “Tha’ fellow doan’ never humbug us. We eats them down here, Chief.”

“Eat them!” exclaimed Frank in surprise. “Gee! I’d hate to eat the slimy things. But I thought they attacked divers, pulled them down with their tentacles and killed them.”

“No, sir!” declared the boatman. “Tha’s jus’ foolishness. 'Cose a big fellow might humbug a diver, but Ah ne’er knew o’ such a happenin’ an’ Ah was spongin’ fo’ ten years an’ mo’.” Then a broad grin spread over the man’s face and he shook silently as though laughing to himself over some amusing memory. “Yaas, sir,” he went on. “Come to take consideration o’ the matter Ah did know o’ one o’ tha’ fellows makin’ to fight with a diver. Yaas, sir, a almighty big fellow—jes erbout three fathoms across he was, Chief. Yaas, sir, he went fo’ to make trouble with Mr. Rawlins, Chief, jus’ fo’ to commo-date the picture, but tha’ one was a tame orctopus—made out o’ rubber an’ springs fo’ the occasion, Chief.”

“Oh, yes, we heard about that,” said Tom, “but do you know Mr. Rawlins?”

“Bless yo’ soul, yaas, sir,” the negro assured him. “’Cose Ah knows Mr. Rawlins, ev’yone here knows he. Why, Ah been we’kin fo’ Mister Rawlins fo’ mos’ two years, Chief. Does yo’ know he too, Chief?”

“Oh, slightly,” replied Frank casually, realizing that they had not adhered strictly to their motto. “But how about sharks? Don’t they attack people in the water?”

The darky fairly guffawed with merriment. “Ah speculate some folks been a yarnin’ to yo’,” he declared. “Yaas, sir, das’ it. Sharks! Lord a’mighty 'cose tha’s sharks plenty hereabouts, but no one don’ make no flust’ration 'bout those fellows, no, sir! Why, Lawd bless yo’ soul, Chief, we Conchs goes down an’ kills sharks weselves. Yaas, sir, jus’ take a knife erlong an’ cotches hoi’ o’ a fin an’ slashes of them.”

“Gosh! then it’s true after all!” cried Tom. “The purser on the ship told us that, but we wouldn’t believe it.”

But despite the boys’ desire to see a shark and their boatman’s promise to demonstrate the fact that it is an easy matter to kill a ten-foot man-eater single-handed in his native element, none of the sea tigers presented themselves for the sake of the exhibition.

“Tha’ don’ is such a plenty o’ sha’ks roun’ here 'bout as tha’ was,” the boatman informed them when the boys expressed their surprise at seeing no sharks in waters which they had imagined teemed with them.

“Yo’ see tha’ tourists an’ folks what comes here-'bout cotches he an’ shoots at he an’ causes such a flustration 'mongst ’em tha’s mos’ all scared away, Chief. Yaas, sir, I 'spec’ if yo’ wants to see sha’ks yo’ll bes’ take a cruise 'board one of tha’ spongers. Tha’s plenty o’ sha’ks roun’ erbout tha’ cays an’ the sponging grounds.”

But the boys did see an octopus or “sea cat” as the natives call them. As they were returning to Nassau they passed a fishing boat and going alongside to see what the men had caught they were shown one of the devil fishes which had just been hauled up from its home on the ocean floor. It was not a large specimen—barely five feet across its outstretched tentacles, but as it writhed and squirmed upon the sloop’s deck the boys shuddered at its sucker-covered, snake-like arms, its hideous pulpy body and its cold, cruel, lid-less, unwinking and baleful eyes.

“Gosh! how can any one eat such things!” exclaimed Tom.

“And say, just imagine being tackled by such an awful beast down under the sea!” added Frank. “I’d die of pure fright, I believe.”

Little did the boys realize that they would have a chance to test their sensations under such circumstances and little did they know that the delicious, thick, stew-like soup which they had enjoyed so much was made from the repulsive octopus.

When the boys reached Nassau they found a trim little gray destroyer anchored off the town and the American flag, flapping gently in the breeze at her stern, left no doubt as to her nationality.

“Oh, say!” cried Frank. “There she is! Gee! why weren’t we here when she came in?”

“May not be,” declared Tom. “Lots of American destroyers drop in here and we won’t miss anything anyhow. The boat’s only reaching the dock now. She must have just come in.”

By the time the boys stepped ashore the officer from the destroyer’s boat had entered a rattle-trap carriage and had driven away, while about the white-clad bluejackets in the waiting cutter were crowds of blacks, laughing and jabbering and striving to sell the sailors everything from seed necklaces and bits of coral to pineapples and mangoes.

As they pushed through the close-packed, brightly-garbed throng the boys caught a glimpse of one broad-shouldered sailor who was arguing over a bunch of bananas with an immensely fat colored woman and instantly they recognized him.

“Say, ’tis the destroyer,” exclaimed Tom. “Look, there’s the bosun’s mate who told us about the schooner. Gee, I wonder if they got her!”

Hailing a carriage, for they were too eager to hear the news to walk, the two boys were driven quickly to their hotel and hurrying to their rooms found Mr. Pauling and Mr. Henderson talking with an officer in a commander’s uniform.

“Hello, just in time, boys!” exclaimed Mr. Pauling as the two appeared. “Commander West just got in and was about to give us the news.”

“I’m sorry it’s not very good news,” said the officer. “In fact no news at all—as far as results are concerned. We sighted the schooner just north of Watling’s island and signaled her to heave to, but she did not pay the least attention. We couldn’t send a shot after her, you know—serious matter to fire on or near a vessel on the high seas, and she was flying the British flag. Before we could come alongside she slipped in between the reefs and we had to slow down and feel our way—dangerous channels those between the coral, you know—and by the time we rounded the next cay she’d completely disappeared. Strangest thing I’ve ever seen. Not a trace of her, if she’d sunk with all on board she could not have vanished more mysteriously. Of course we supposed that she’d slipped into some little bay or cove where we couldn’t follow so we anchored and sent our boats off. They ran around every cay and island within sight, but not a sign of that blessed packet. It gets me, I admit.”

“H-m-m!” muttered Mr. Henderson. “Sort of phantom ship, eh? Was it possible she slipped away behind the islands while you were getting through the reefs?”

“Don’t see how she could,” replied Commander West. “Her topmasts would have shown up somewheres. No, she must have got into some landlocked bay that our men missed—hard thing to see some of those with the fringe of palms along the outer beach hiding the entrance, you know. Well, to continue. We decided to search every cay the next morning—it was pretty near dark then—and we did, but not a sign. Then we gave up and were cruising about, thinking she’d slipped out during the night and we might pick her up and the next day what do you think? Why we got a radio from Haverstraw of the Porter saying they’d sighted her over by the Caicos and that she gave him the slip among the reefs the same way. He had a little better luck though. Found her all right.”

“Hurrah!” shouted Tom as the commander hesitated. “Did they get the men?”

“They found her, as I said,” continued the officer, “anchored off one of the cays and—absolutely deserted!”

“Jove!” exclaimed Mr. Henderson. “Deserted! Confound those fellows. They seem to have a habit of deserting their ships! First the submarine and now the schooner. Did Lieutenant Haverstraw find anything on her?”

“Nothing suspicious,” replied the commander. “To all intents and purposes she was merely a fishing smack. Didn’t even have a wireless aboard. He might have towed her to port as a derelict, but he radioed for advice and I told him to leave her. If he’d brought her in there might have been too many questions asked—Admiralty investigation and all—these Britishers are just as particular about a smack as a liner when it comes to maritime law, you know, and they have a blamed uncomfortable way of asking too many questions sometimes. Of course I realize that the two governments would straighten it out and keep matters quiet, but the local authorities might not and she’s just as well off there as here as far as I can see.”

“Yes, no need of arousing curiosity,” agreed Mr. Pauling. “Did you search the islands near her to see if the men had gone ashore?”

“Haverstraw tells me he even looked inside the conch shells on the beach,” replied the officer with a laugh. “Says if he finds another abandoned ship he’ll resign—getting on his nerves. He’s the one who picked up the submarine, you know. However, I’m sailing for the Caicos this evening—if those men are on any of the cays or took to another vessel we’ll find them.”

“Oh, I’ve an idea!” exclaimed Tom who had been thinking rapidly. “If those fellows on the submarine deserted her and took to the schooner as we thought, perhaps they left the schooner and went to a submarine.”

“Well, I’ll be——” began Mr. Henderson. “Why in thunder haven’t we thought of that before? What did I tell you, Pauling? Didn’t I say these boys would give us old hands some new ideas? Jove! I’ll wager that is the solution. Probably knew where the sub was waiting and made for it. Had her ready for just such an emergency.”

“That may be it,” admitted Commander West, “but if ’tis where in the name of the Great Horn Spoon do they get the subs? They’re pretty darned expensive little toys, you know, and a chap can’t buy or build one the way he can a skiff. Seems to me some one would have known if there were mysterious submarines knocking about.”

“It is a mystery,” agreed Mr. Pauling, “but the whole affair has been full of mystery. I think, however, there may be a simple solution to this one. If we assume that the head of the organization is whom we suspect it to be he might well have obtained German U-boats. We must remember that in his original undertaking he possessed unlimited means and almost unlimited authority and had the confidence of the Prussian government. Is it not possible or even probable that he had several sub-sea craft on this side of the Atlantic—we know he made use of one in his nefarious scheme—and that with the failure of his plans and the collapse of Germany he appropriated the subs for his own private designs? The crews in fact might have joined with him—we have proof that some of those on the captured U-boat were formerly in the German navy and if he has a secret headquarters down here is it likely he would risk all on one submarine?”

“I imagine your theory is very nearly correct,” replied Mr. Henderson. “If so, there is little use in attempting to accomplish anything until Rawlins arrives. When should he be here, Commander?”

“That’s hard to say,” replied the officer. “We had a code message several days ago to the effect that she had completed refitting and was expected to sail any time. If she left the following day—let’s see, that was last Friday—she might be at her rendezvous by day after to-morrow—Thursday. I should hardly expect her before then. But Disbrow is posted near there and will undoubtedly notify you the moment she is sighted. You know the plan was for Rawlins to signal our ship about thirty miles off the island and then run submerged to avoid any possibility of being seen. Then Disbrow will radio you—Rawlins’ outfit might not reach you and a simple and innocent-appearing message from Disbrow would excite no comment. Well, I must be getting off. If we stay here too long these Conchs will wonder why we’re here. I gave out we just dropped in for fresh vegetables and fruit and I expect my gobs have loaded up by now.”

After the commander left, the conversation was all of this latest development in the search for the mysterious conspirators and every phase and theory was thoroughly threshed out without coming to any more definite conclusion than before.

“It’s just one confounded disappearance after another!” declared Mr. Henderson. “I shouldn’t be surprised now if Rawlins vanished or even if that Smernoff had gone up in a wisp of smoke.”