"Miss Peddensen," murmured the lieutenant commander, "may I see what you are writing?"

The woman looked up, her face composed, her eyes dancing with mirth.

"Why, surely, Mr. Kimball," she replied, laughing. "And very silly stuff you'll find it, too. I have been jotting down my impressions upon finding myself riding under the surface of the sea. I do not handle your English language very well, as you will see."

Mr. Kimball glanced hastily through the three or four pages of rather closely written note paper. It was, as the young woman had stated, a very amateurish composition, in very stilted English.

The naval officer felt a sense of mortification and his face reddened slightly. He had been led to expect that he would find something crime on these sheets of paper. Instead, he scanned a stupid piece of composition.

"I would die of humiliation, to have that read before all these people," murmured the young woman.

Lieutenant Commander Kimball gave Jack Benson a covert elbow-dig in the ribs, a move said, as plainly as words:

"The joke is on you."

Jack, however, through half open eyes, had been watching on his own account. Suddenly he made a dive forward, shooting his hands down close to Miss Peddensen's well-booted feet.

"That same old ship-rat!" exclaimed the submarine boy. "I'll catch the beast before he goes under your skirts, Miss Peddensen."

At the mention of a rat so dangerously close young woman almost shot out of her seat in anxiety to get away.

As she bounded something dropped down out of the wide right sleeve of her coat. It was a small memorandum book.

This was just what Jack Benson caught, in place of the pretended rat. Moreover, the young skipper was clever enough to catch the book so that it fell into his hands open.

"It wasn't a rat, after all, Miss Peddensen," smiled Jack, straightening up and holding the open memorandum book so that both he and Kimball could see what was traced on the two pages that lay exposed.

There were sketches of the compressors, sketches of the mechanism by which the compressed air was forced into the tanks to drive the water out—in fact, sketches of many vital features in the control of the boat. Nor was more than a glance needed to make it plain that this young woman artist possessed expert knowledge of machinery.

At the cry of "rat" three or four women jumped from their seats. The one nearest Miss Peddensen moved hastily to the forward end of the cabin.

"My dear young woman," murmured the lieutenant commander, dropping into the vacated seat beside the Swedish girl, "you won't mind, will you, if I keep these little matters to look over at my convenience!"

There was something so compelling in the look that flashed briefly in the naval officer's eyes that Miss Peddensen lost color, and stammered:

"No-o-o, certainly not; if such silly things interest you."

"They interest me very much indeed," murmured Kimball, thrusting "composition" and sketches inside his blouse.

As the naval officer plainly intended to remain where he was, Jack Benson turned, sauntering forward.

"Another spy nailed, beyond a single doubt," muttered the young submarine commander. "Will there never be an end to them."

As Captain Jack glanced at the young Englishman, Drummond by name, he saw an unmistakable flash of hostility in the Englishman's eyes.

"So you're a spy, too?" quivered Benson, inwardly, turning on his heel. After that, howsoever, the submarine boy took good care to keep Drummond under covert watch.

In time the "Benson" returned to the surface, being now much nearer land then when the aft had made its dive. A few minutes later the boat ran into the harbor and made fast at its moorings.

"What are you going to do about the young woman?" Jack found a chance to whisper, as all hands gathered on the platform deck.

"I don't believe I have actual authority to do anything," Kimball returned, also in a whisper. "But we have the drawings, and that writing, which may be a clever cipher. With that I'm afraid we'll have to remain content."

A launch from the gunboat was in waiting. In this the shore guests were taken back to land. Hardly had the launch left the side of the submarine, when a cutter, also from the gunboat, put in alongside. Two men in ordinary citizen's dress clambered aboard.

"Lieutenant Commander Kimball?" inquired one of the pair.

"Yes," acknowledged the naval officer. "May we see you below, in the cabin of this boat."

"No!" replied Kimball, sternly.

"Oh, as you please, of course," smiled the one of the pair who had first spoken. "Probably I am at fault, though, in not introducing my companion and myself. My friend is Mr. Packwood; my name is Trotter. We are Secret Service men sent down here by the Secretary of the Navy, in answer to your dispatch."

As Trotter spoke he threw back the lapel of his coat, displaying a badge.

"I have also some papers to show you, Mr. Kimball," continued the Secret Service man.

"Oh, of course you may come below," smiled the naval officer. "And, Benson; I guess this business belongs to you, too."

So Jack descended with the party, while the other submarine boys and Williamson remained on deck.

"You have, been bothered with spies, Captain?" asked Trotter, turning to young Benson, when they had reached the cabin table.

"Haven't we, though!" muttered Jack.

"And even took one out with you on this last trip of yours," laughed Mr. Trotter, producing from an inner pocket a book bound in black.

"Miss Peddensen, the Swedish young woman?" demanded Captain Jack.

"Here's the one I mean," replied Trotter, opening the book, which proved to be an album, and turning the pages over rapidly. He pointed to a photograph.

"That's Miss Peddensen," cried Jack, looking up at Lieutenant Commander Kimball for confirmation.

"Well, Peddensen is one of the names she has used," smiled Trotter.

"What foreign government does she serve?" demanded Benson.

Trotter shrugged his shoulders.

"Well, the Department has pretty good information that she has served England, France, Germany, Austria, Russia—oh, these spies have no country! They serve the fattest international purse!"

"Here is what we took from Miss Peddensen," said Kimball, gravely, laying down on the table the sketchbook and the "composition."

Taking up the latter, Mr. Trotter, after a glance declared:

"This is written in a secret cipher, most likely. Packwood, this comes in your peculiar line of work. The sketches are easy enough to understand. They are of the mechanisms displayed in this cabin."

"Yes, this is a cipher," declared Packwood, thoughtfully, after scanning the sheets a few moments. "With some study I can make it out."

"Who's the young Englishman who escorted Miss Peddensen?" demanded Captain Jack.

"Never saw him until I glanced at him in the launch just now," replied Trotter. "He may be another spy, unknown to us, or he may be merely a good-natured and wholly innocent young chap whom the Swedish girl has lured into her service."

"What are these other pictures?" inquired Mr. Kimball, beginning to turn the leaves.

"All of 'em photos of people known to be engaged in stealing naval secrets for foreign powers," replied Trotter. "Captain Benson may keep this album for future use. I've another copy for you, Mr. Kimball."

"Why, here's a good likeness of Mlle. Nadiboff," cried Jack Benson, pausing in turning the leaves and glancing down at the picture of a face he had good cause to remember. "And here, opposite her, is M. Lemaire!"

"Oh, yes; they're both old offenders," nodded Trotter. "Turn along, and see if you remember any more faces."

"Here's Gaston, who is now in jail here," nodded Jack.

"Is he, though?" asked Trotter, with interest.

"What charge?"

"Felonious assault upon Hastings and myself."

"Good," chuckled Trotter. "I shall have to see the judge privately, and ask him to make sure that Gaston Goubet gets the longest sentence possible. Nothing like prison bars to stop the work of these international spies!"

"Why, here's even little Kamanako," smiled as he turned over another page.

"Yes, and a very smooth and slippery little spy that Jap is," declared Mr. Trotter. "He steals all kinds of secrets, from the details of sixteen inch guns down to the method of dyeing a blanket in a mill."

"Are you going to do anything with the Peddensen woman?" inquired Lieutenant Commander Kimball.

"Ain't I, though—just!" answered Mr. Trotter. "You caught her red-handed, with drawings, cipher and all."

"Will she be imprisoned?" inquired Captain Jack.

"Well, that isn't the usual way," replied Trotter. "The young woman is more likely to be taken to New York, given a passage ticket across the ocean, and notified that, if she tries to return to this country, she will find that her photograph is on file at every port of entry. It will spoil her games, without making much of a fuss."

The cutter waiting alongside conveyed Kimball and his brother officer, Featherstone, back to the gunboat. Then it ran into shore; putting Mr. Trotter and his silent companion once more on land.

For some minutes after that Jack, Hal and Eph remained absorbed in the pictures in this album of known naval spies. There were more than two dozen of these photographs, some of men, some of women. On the same page with each picture was given the subject's true name, if known, also the spy's aliases, and other information.

"Sara Nadiboff, twenty-nine, yet looks like twenty," muttered Hal, studying the information under the young Russian woman's photograph.

"And Kamanako is really Lieutenant Osuri," muttered Jack. "Yet the fellow was working in the hotel kitchen until he could get a chance to apply for a job on this craft."

"I don't recognize any other spies among these pictures," muttered Hal. "The only ones here that we know we had already guessed."

"Look at that time," muttered Jack, jumping up. "I must get on shore and see what Mr. Farnum's orders are. And—" thrusting the album in his coat pocket and buttoning it up, "I'll take this picture gallery along. Our employer will be highly interested in it."

It was dusk by the time that Benson reached the platform deck. After a few moments he succeeded in hailing a harbor boat. Yet it was quite dark by the time that Captain Jack stepped on shore.

Instead of going around by the road Jack decided to cross the grounds. As he was walking briskly toward the hotel, an athletic-looking young man stepped out suddenly, from behind of the big trees, blocking the submarine boy's path.

"Good evening, Mr. Drummond," Jack hailed, quietly.

"Now, you halt and stand right where you are," retorted the Englishman, nervously handling a heavy walking stick that he carried. "I don't know whether it's going to be a good evening for you, or not, young man. Do you know that your cursed meddling has resulted in the arrest of a most estimable young woman?"

"Who?" asked Jack, coolly.

"Miss Peddensen," replied Drummond, angrily.

"Oh, I guess the secret service men know what they're about," said Jack somewhat sarcastically.

"And I know what I'm about, too!" roared the enraged Drummond, raising his cane, wrathfully. "Benson, you young sneak, I'm going to brain you!"



CHAPTER XVII

DRUMMOND'S LITTLE SURPRISE—FOR HIMSELF

It didn't happen just that way.

As Drummond swung his cane and brought it down with crushing force, aimed at the submarine boy's head, Jack wasn't there.

Instead, Benson sprang about two feet to one, side. It would have been a fearful blow had Jack's head been in the way. As it was, the cane hit the ground with such force as to be thrown from the Englishman's hand.

With a growl, the fellow leaped forward and snatched up his stick. Jack Benson stood leaning carelessly against a tree, in a way that enraged Drummond all the more.

"I'll show you!" snarled the Englishman. With that he aimed a blow, sideways, at Benson's head Jack ducked, then dodged out. The cane hit the tree with a force that jarred the assailant and all but dislocated his wrist. Again he dropped the stick.

Benson gave a hearty ringing laugh and this enraged the Englishman past endurance. Then Jack added, "Is that the best you can do?"

"I'll show you!" roared the other, making a leap forward. He charged straight at the submarine boy, who wheeled and darted on toward hotel.

"Don't run, you coward!" came the flying taunt.

Just then Jack Benson fell, though he did it on purpose. Straight in the path of the irate Englishman the submarine boy dropped, curling himself up.

It was too late for Drummond to halt, or to change his course. He tripped over prostrate young Benson, then lurched forward landing on his face.

Up sprang Jak Benson, planting two sterling good kicks.

"You beast! Wait until I get up!" roared the victim, in a voice like a bull's bellow.

"What's the matter here?" demanded an astonished voice, and Mr. Trotter, after a short dash, bounded through the darkness, arriving on the scene just as Drummond was getting up.

"This fellow—" began Jack.

"'Fellow'?" broke in Drummond, angrily.

"This fellow," Jack continued, calmly, "accused me of causing Miss Peddensen's arrest, and promised to brain me."

"Too bad you've allied yourself with that young woman," muttered Mr. Trotter looking keenly into the Englishman's face.

"What d'ye mean?" demanded Drummond.

"Miss Peddensen turns out to be a well-known military and naval spy, though she hasn't operated in this country before in five years," replied Mr. Trotter, coolly. "However, she has been caught trying to steal the secrets of the submarine boat, and she's under arrest. My side partner, Packwood, is now engaged in unraveling a cipher that was taken from her."

"That's an impudent lie," asserted the Englishman, hotly.

"No it isn't," laughed Mr. Trotter. "It's a Secret Service fact."

"I'm going to go to Miss Peddensen, now, then," asserted Drummond.

"Right-o," drawled Trotter, so significantly that Drummond shot a quick look at the officer, demanding:

"What d'ye mean by that?"

"I'm going to take you to Miss Peddensen," returned the Secret Service man.

"I'll go all the way to Washington, by tonight's express, to see the young lady freed from this outrageous mistake," stormed the Englishman.

"I don't know about your going to Washington—to-night," replied Trotter, yawning.

"What have you to do with that?" demanded Drummond, harshly.

"Why, I reckon, Mr. Drummond, you're my prisoner. You won't very easily go anywhere to-night, without my consent."

"Your prisoner?" demanded the Englishman angrily.

"Yes."

"By what right do you arrest me! What have I done?"

"Well, for one thing, you've tried to injure the captain of the submarine boat, all because he caught your woman friend at strange tricks on board the 'Benson.' For another reason, because we suspect anyone who defends or upholds the spy. Be good enough to step along with me, Mr. Drummond."

"I'll do nothing of the sort," blurted the astounded Englishman

"You'll go all the same," warned Mr. Trotter, first of all displaying his Secret Service badge, next running a hand back briefly to a revolver that rested in a hip pocket. "I don't much care, Drummond, whether you walk with me, or whether I have to send for an ambulance to bring you along. But you'll go just where I want you to."

The Englishman was too much terrified to reply. Two or three times he opened his mouth as though to speak, but, instead, merely swallowed.

"Come, now—forward march" advised Mr. Trotter. Drummond, without allowing himself to hesitate, went away at the side of the Secret Service man.

"Don't you want your cane?" called Jack Benson. Drummond did not condescend to answer, so the submarine boy slipped back to the tree, where he found the stick. It was a handsome piece of polished partridge wood, surmounted by a handsomely wrought head of gold.

"This will make an interesting souvenir to keep aboard the boat," mused Benson, swinging the stick as he continued his walk.

At the veranda Jack came face to face with Mlle. Nadiboff, just returning from an unaccompanied stroll down by the water front. To the submarine boy's astonishment the handsome Russian greeted him most amiably.

"You have not forgotten old friends, I hope, my Captain?" she added, smiling and with a pretty little coaxing way.

"There are some old friends," replied Captain Jack, lifting his cap, "whom it is impossible to forget."

"I hope you will continue to regard me as a friend," responded Mlle. Nadiboff, more seriously, looking him fully in the eyes.

"Why?" queried Jack.

"I may need a friend," she replied, dropping her glance for a moment.

"You in need of anything—even a friend?" cried Captain Jack, incredulously.

"I may need a friend who can speak a good word for me; who can forget things, or explain them." went on Mlle. Nadiboff, resting a hand pleadingly on his sleeve "My Captain, if need be, I shall send for you. Do not fail me! You won't?"

It looked as though the tears lay just behind her eyes. The submarine boy felt that the situation was becoming too interesting, so he lifted his cap once more as he turned on his heel.

"Mlle. Nadiboff," he sent back to her, "I trust you will never want for the most reliable friends."

He turned down the veranda to go toward the office door, when he encountered another surprise.

Leaning against one of the posts stood Kamanako, as natty and trim as though he had come from the tailor's.

Looking up with a most friendly smile, the little Japanese saluted.

"Why, how do you do?" Jack greeted him, halting. "I had an idea you had left Spruce Beach."

"I should have done so, but I started too late," replied Kamanako, still smiling. Nothing ever daunts that Japanese smile. One of these little men, being led away to have his head chopped off, goes with a smile on his little brown face.

"Started too late?" asked Jack. "How was that?"

"Now, you laugh at me," replied the Japanese.

"Laughing at you? Not a bit!"

"You have told some one that I am a spy," replied Kamanako, without a trace of grudge in his voice. "So now, I cannot leave Spruce Beach. Ticket agent, he will not sell me. If I try to go on foot, the roads are watched. If I take to woods, even, I shall be found."

"Sorry," nodded Jack Benson, and passed on. "So the Secret Service net is around the place, and no suspected person can get away?" muttered the submarine boy. "Well, that's it should be. I wonder if there are any more of this strange crew—men or women spies that don't happen to have suspected so far? If there are, I don't believe they'll wriggle through the meshes of old Uncle Sam's Secret Service net, anyway."

His mind full of the doings of the day, Captain Jack Benson found Messrs. Farnum and to whom he surely had much to tell.



CHAPTER XVIII

"REMEMBER WHAT HAPPENED TO THE 'MAINE'!"

"We'll have no more trouble, I imagine," nodded Jacob Farnum, with a satisfied air, when Jack, at a table in the corner of the dining room, had told, in low tones, all that had happened.

"The spies are all on the defensive, now, beyond a doubt," added David Pollard. "They'll be too busy keeping their wrists out of handcuffs to devote any of their time to trying to get at the secrets of the 'Benson.'"

"I hope you're both right," said Captain Jack, gravely.

"Why, what leads you to think that we may not be?" asked Farnum, curiously.

"Nothing in the way of facts," Jack admitted. "Yet there may be others of this infernal spy gang who have not yet shown their hands, of whose existence the Secret Service knows nothing."

"Well, what can they do, if you don't allow any strangers on board the boat?" asked Mr. Farnum, point blank.

"Nothing much," muttered Benson, "unless—"

"Well, unless what?"

"See here," asked the submarine boy, "what is usually done to such spies by the United States Government?"

"Why, the law provides that, in war time, such spies can be shot in mighty quick order," replied Mr. Farnum. "In peace times the law doesn't allow anything but sending spies to prison."

"But what does the Government usually do?" pursued Captain Jack. "It seems to me I've read of suspected spies being caught around American fortifications, trying to make notes, or take photographs."

"Yes," nodded the shipbuilder.

"And I think I've read, also, that such spies are generally warned and then let go."

"That's the usual procedure, I believe," admitted Farnum.

"Then, after the spies who have been bothering us have all been rounded up and scolded, they'll be given railroad tickets and allowed go on their way?" asked Jack.

"Frankly, I'm afraid that's just what will be in the present case," admitted Jacob Farnum.

"Then," grumbled Captain Jack, making a rather wry face, "it would seem that being a foreign spy, in this country, provides one with a calling that is a good deal safer than being just a lightning rod peddler or a bill collector."

"Yes; it's really so," admitted the shipbuilder, thoughtfully.

"If that is the case," muttered Captain Jack, "the spies here at Spruce Beach will probably keep a bit quiet until they see how things are going to turn out. As soon as their minds are made easy by our generous government, then they'll plot their next moves. If they can't accomplish anything more, they may content themselves with a general revenge of some sort on the whole lot of us."

"You're not afraid of their vengeance, are you?" asked Mr. Farnum, looking up, and into the eyes of his young captain.

"I'm not afraid, of anything, sir," retorted Jack. "The master of a submarine boat has no right to be afraid of things. Even if these scoundrels should get me, in the end, all I can to is to smile, and say: 'So be it.'"

Then, in the next breath, Benson added, earnestly:

"It doesn't matter so much if these rascals get me, but I don't want them to work any mischief to the submarine."

"Bravo!" nodded David Pollard, looking on with a smile.

It is a fact that life in a constant atmosphere of danger renders the average man all but indifferent to fear. Those who meet perils daily grow to consider danger as all a part of the day's work. Perils which, a year before, would have kept Jack Benson awake with dread for a week now appeared to him as not worth thinking about until they happened.

Jack remained ashore until half-past nine. He hoped to hear some word of what the Secret Service men might have learned, or of what these representatives of Uncle Sam were doing. But no word came, so the submarine boy went down to the beach. There was but one harbor boat in sight.

"Ah done thought yo'd be gwine back to do little ship, sah, so Ah done waited fo' you'," explained the negro in the boat. "Any mo' ob yo' pahty to go abo'd to-night, sah?"

"No," Jack answered. "I'll be the last one to put off to-night."

Nor did he forget to reward the darkey's enterprise by handing him rather more than the usual boat hire.

As he stepped aboard Jack found Hal pacing the platform deck.

"Keeping deck watch, old fellow? I'm glad see that," Captain Jack said, commendingly.

"Yes; I'm on until midnight. Then Williamson stands watch until three-thirty in the morning. After that Eph comes up and takes the trick until it's time to call us all."

"When do I come on watch?" asked Jack.

"I never heard the captain of a craft had to stand watch in port," laughed Hal Hastings "Besides, old fellow, we couldn't be sure you'd be aboard to-night. So the watches are all arranged. Anyway, you'd better turn in and get a full night's sleep, for you've more on your mind than the rest of us."

"Then tell Williamson, and have him pass the word on to Eph, that watch ought to be very strictly kept," answered the young captain.

A few minutes Benson remained on deck, chatting with his chum. When he at last went below the submarine captain lost little time getting into his berth.

When Machinist Williamson came on deck at midnight a light wind was blowing, but the air was not really chilly. In his heavy reefer the machinist felt wholly comfortable after he had lighted his pipe and started his slow walk back and forth along the deck.

There did not appear to be overmuch sense in keeping this deck watch. Only a short distance away lay the United States gunboat "Waverly," with her alert marine guard. Though there was no moon, the starlight was bright enough to enable a marine on the gunboat to see anything that might skim over the water toward the "Benson."

Yet Williamson was on watch, under instructions, and he was a faithful fellow who meant to do his full duty.

"Seems kinder tough, of course, to be so long out of one's bunk in the middle of the night," the machinist admitted to himself.

Yet, had his vision been keen enough to know what was happening on shore, almost directly opposite the "Benson," Williamson would have been tenfold more alert.

Over there on the shore, in a clump of flowering, semi-tropical bushes, crouched two men. On the ground with them lay a metal cylinder some two feet long and seven inches in diameter. There was also a coil of wire and a boxed magneto battery.

One of the pair held to his eyes a pair of night marine glasses. Incessantly this watcher kept his gaze focused on Williamson.

About two o'clock in the morning Williamson found it necessary to go below for a few moments. After reaching the conning tower he paused, for a few moments, to look keenly all about him.

Yet, look as he would through the night, the machinist's vision could not see that the bush hidden pair on shore, guessing his intention from his stop by the conning tower, had silently taken to the water. With them they towed the metal cylinder, which floated. To the cylinder was attached one end of the light wire.

Some distance out from the shore the pair halted, treading water, only their eyes above the surface. But Williamson could not make out such small objects at the distance. Then he went below.

"Now, for it," breathed one of the swimming pair, tensely.

Both swimmers struck out strongly, yet silently, making fast progress through the water by means of some of the best strokes known to swimmers.

When they reached the port side of the submarine Williamson was still below. Nor had the attention of the marine guard on the "Waverly" been attracted.

In just another swift instant the swimmers made a dive that carried them and their cylinder below the surface.

Straight up against the bottom of the hull the pair went.

When they returned to the surface the metal cylinder was in place below.

Glancing backward only once, to make sure that Williamson was not yet on deck, and that the gunboat's marine guard had not detected their stealthy work, the swimming pair struck out lustily for shore.

Back into the same clump of bushes they made their way. In the first few moments neither of the recent swimmers appeared to dare a glance into the face of his comrade. In silence they fitted the shore end of the wire to the battery.

Then one of the pair seized the handle to pomp the fatal electric spark along the wire to the hidden mine under the "Benson's" hull.

"Remember what happened to the 'Maine'!" this wretch chuckled hideously.



CHAPTER XIX

A JOKE ON THE SECRET SERVICE!

"What's that noise?" wondered Williamson.

He stopped, listening intently, for he was still below.

Against the bottom of the "Benson's" hull he heard a steady, slow, monotonous bumping. As he listened, his face took on an anxious look.

"We're in a friendly port," muttered the machinist. "It can't be anything very wrong, and yet—"

That slow steady bumping continued.

"Anything bumping against the bull of a boat at anchor, in that fashion may be wrong," concluded the man, swiftly.

His mind made up to this much, the rest was not difficult to decide. The cause of that bumping required instant investigation. Williamson caught up the tool that came quickest to hand, a pair of nippers, thrust them into his jumper and raced up to the deck.

"If it's any real mischief," he muttered, "I hope I won't be too slow—too late!"

With that he dived overboard, at the starboard rail, the side nearest the gunboat. There was a splash—then the waters closed over the machinist.

He came up at about the point he had planned, where he had heard the bumping.

Held below water as he was by the under-hull of the submarine, he could move with certainty, though but slowly.

Groping, the machinist encountered the metal cylinder. Quickly he felt for its connections which, like a flash, he knew must exist. He found the wire, but reached for another. It all had to be done swiftly, for his reserve "wind" was fast giving out. Not finding a second wire, he fastened his nippers against the first wire—then cut. Now, steering the metal cylinder, he pushed it out from under the hull. Cylinder and man rose together.

Whew! What a powerful breath the man took! Then he steered the cylinder carefully against the hull, and managed to hold it there until he could reach a piece of cordage and make the cylinder fast.

This done, he dashed below, thumping hard on the door of the stateroom occupied by Captain Jack Benson and Hal Hastings.

"Eh? What is it?" called Jack, almost instantly.

"You're wanted on deck, Captain—instantly," replied the dripping machinist.

"Oh, all right, Williamson," and Benson's feet hit the stateroom floor.

A minute later he was above, Hal following only some twenty seconds behind his young chief.

Williamson swiftly told how he had heard the bumping against the hull, and how he had found the cylinder, with a wire connection.

"Gunboat, ahoy!" roared Captain Jack, snatching up a megaphone and holding it to his lips.

The response was prompt. In less than three minutes a cutter, containing an officer, a corporal and four marines, was alongside.

"The first thing for us to do is to take that cylinder aboard the 'Waverly' and investigate it," decided Ensign Foss. "I'll leave the marines here until I get further instructions from the commanding officer."

"Anything happening?" demanded Eph, reaching deck just after the cutter had put off. He eyed the marine squad curiously.

"Just what we're trying to find out," replied Jack.

"It must seem to you that I acted amiss in leaving the deck," put in Williamson.

"But you didn't," retorted Jack. "Had you been on deck you wouldn't have heard that infernal machine bumping against the hull."

"Infernal?" echoed Eph Somers, rubbing his eyes. "Say, have I been missing a whole lot by being asleep?"

The other three told him quickly all they knew of what had happened.

Within five minutes the cutter came back, bringing two more marines and a young second lieutenant of that corps.

"Lieutenant Commander Kimball's compliments, sir," reported the second lieutenant. "He will put in an appearance as soon as that cylinder has been investigated. He has sent me with instructions to see what had best be done."

"I don't believe there's much doubt as to what had best be done," replied Captain Jack, quickly. "Williamson reports having cut a wire that was attached to that cylinder. I think we can find that wire again, and, if we do, we can easily follow it to its other end."

"By jove, that's good enough," muttered the lieutenant.

"Williamson is already wet," proposed Jack. "He can dive again, and see whether he can pick up that wire. If he needs any help, I'll go overboard with him."

"Wait until I see what I can do," proposed the machinist.

This time he dived over the port side of the craft. Three or four times he came up for air, next going, below again. At last, however, Williamson came up, calling:

"I have a part of the wire in my hands."

Lieutenant Foster ordered his marines into the cutter, inviting Jack and Hal also to go with him. They rowed out alongside of Williamson, picking up the machinist and his wire.

"We'd better put your man back on the boat, hadn't we, Mr. Benson?" inquired the marine lieutenant.

"I'm not such weak stuff as that, sir," almost grumbled the machinist. "I can stand a few minutes more in wet clothes, and I want to go along to see where this wire leads."

"Good enough," nodded Lieutenant Foster, he gave the order to row along slowly, while two marines in the bow of the cutter slowly gathered in the wire, at the same time signaling back the direction in which it lay.

Only a few minutes were needed thus to follow the trail straight to the clump of bushes on shore.

"Nobody leave the boat until we have a lantern ready," directed Lieutenant Foster. "We don't want to tramp out the trail of the rascals who laid that mine."

The marine lieutenant himself was the first to step ashore, and Jack Benson was with him.

"Here are the footprints of the rascals," announced Foster, as the two stepped cautiously into the bushes.

"Yes; there were just two of them here, apparently," replied Jack, after studying the prints, and discovering the marks of only two different sizes or kinds of shoes.

"Here's the imprint of a box," added Foster. "Good heavens, the scoundrels had a regular magneto battery, insulated wire and all, for firing that mine from the shore. Mr. Benson, they meant to blow your boat into Kingdom Come!"

"It looks that way," replied Jack Benson, composedly.

On hearing that voice, so even and unaffected in its utterance, Lieutenant Foster looked at the submarine boy keenly.

"By Jove, Benson, you're cool enough to be an admiral," muttered the marine officer, admiringly.

"Why, this doesn't seem to be a joke on me," replied Captain, Jack, smiling back at the lieutenant.

"A joke!"

"It's one on the Secret Service," laughed Jack, quietly. "They are the ones who are supposed to have the job of keeping off spies and all of their kind."

"Yes; this certainly came from the spies, or their friends," muttered Lieutenant Foster. "Jove, but we have a desperate crowd to deal with when they'll go to such a length as this in time of peace!"

"Oh, it may all turn out to be a joke," put Hal, quietly. "Some one may have been doing this to try us out. That metal cylinder may prove to have been loaded with ginger-bread or peanuts. If anyone has been trying a joke on us, then I'm mighty glad we didn't get rattled."

"I reckon we shall soon know just what that cylinder did contain," muttered Lieutenant Foster. "Here's another cutter coming from the 'Waverly,' and I think I make out Lieutenant Commander Kimball in the stern-sheets."

It was, indeed, the lieutenant commander. As he stepped ashore, his face coming into the circle of light cast by the lantern, his features were seen to be white with anxiety.

"We have just looked into the cylinder," he announced, in a low voice. "We found there enough gun-cotton to blow the 'Benson' into inch pieces. It was a fearful crime to plan."

Jack Benson and Hal Hastings heard, but did not change color. There was no sense in losing nerve over a disaster that had been averted in time.

"The first thing to do, of course," continued Lieutenant Commander Kimball, "is to send instant word to Messrs. Trotter and Packwood. They have a heap of work ahead of them."

"As to our own boat's crew," replied Jack, "I fancy the best thing we can do is to go back on board, since we can't do anything here. One of us will keep watch, and the rest of us can get some of a night's sleep yet."

"Why, yes, if you youngsters can sleep, after such happenings," laughed Kimball.

By this time Lieutenant Foster and two of his marines had followed the trail of footprints as far as the hard road. Here all trace was lost.

"What you want to do, Williamson," declared Jack, as soon as the submarine people were back on their own craft, "is to get into some dry clothes and make yourself a pot of hot coffee. Then get in between blankets for a sleep. I'll finish out your watch."

Nor was Benson alone in his watch, for a cutter from the gunboat, containing a corporal and two marines, beside sailors to row the boat, moved slowly around the submarine at a distance of fifteen or twenty yards.

After the rest had gone below, Captain Jack, hanging over the rail of the platform deck, saw other lanterns gleaming in and around the clump of bushes.

"That must be the Secret Service people, pulled out of their comfortable beds," mused Benson, smiling. "Won't they feel upset at any such thing happening hours after they've arrived on the spot?"

After Eph Somers had reported on deck to take his watch, Jack went below, once more dropping into sound slumber. The smell of coffee and bacon was wafted in from the galley when the young submarine captain next awoke.

"Well," announced Eph, as Jack and Hal came forward for their breakfast, "Trotter and Packwood haven't caught the fellows that laid the mine."

"It doesn't look strongly probable that they'll catch them, either," Jack replied. "I don't believe that the fellows who did that trick are any of the regular spies. For that matter, we now of only three spies here who are men. Drummond is under arrest, and so is Gaston. Neither of them could have had a hand in it. And there were two, so, if M. Lemaire was in it, he had an unknown accomplice. But I don't believe M. Lemaire had any personal hand in laying that mine. I've a notion that he considers himself entirely too high class to go into any mere blasting operations."

"'Mere blasting operations' is good," smiled Hal Hastings, "when we stop to think what those 'blasting operations' might have done for us if it hadn't been for Williamson."

"Anyone taking my name in vain?" demanded the machinist, smiling as he put in an appearance at that moment.

"We're trying to see," Eph explained, "whether we can do any better guessing than the Secret Service men as to the fellows who were kind enough to lay that mine under us last night."

"Got it figured out?" asked the machinist, as he transferred, a generous helping of bacon, eggs and fried potatoes, to his plate.

"For myself," put in Hal, "I'd suspect that fellow Gaston, in an instant, if he had only been at liberty. That fellow has an eye that looks like all the letters in the word 'r-e-v-e-n-g-e.'"

"That's so," nodded Jack, thoughtfully, as he ate. "But we happen to know that Gaston is very safe under lock and key. By the way, fellows, I don't suppose Mr. Farnum and Mr. Pollard have heard the news yet, or they'd be out here on the double quick."

After breakfast Jack went ashore alone, to carry the exciting news to his employers. He found Messrs. Farnum and Pollard in the breakfast room at the Clayton. Both were astounded when they heard the news of the night's doings.

"Who on earth could have put up such a job against the submarine?" gasped David Pollard.

"I don't know, sir," Captain Jack replied. "But I've left Hal on board, in command, and I mean to find out something about this business, if there is any way to do it."

With that he excused himself, rising and leaving the table at which his employers were seated.

Jacob Farnum gazed after his young submarine captain, then whispered to the inventor:

"That youngster has some notion in his head of where to look for the infernal criminals. And, ten to one, his idea is a good one that will bear fruit!"



CHAPTER XX

A BRIGHT LOOK AND A DEADLY WARNING

Jack's employer gave him rather too much credit in supposing that the boy had already worked out the problem of finding those who had made the attack on the "Benson."

As the submarine boy left the breakfast room he felt as much in the dark as ever. The only known spies who were still at large, for some reason known only to the Secret Service men, were M. Lemaire, Mlle. Nadiboff and Kamanako.

"This is rather earlier than either of that pair in the habit of showing themselves," muttered Benson, as the first two names crossed his thoughts. "I wonder whether I could get the least bit of an inkling by going to the jail and talking with Gaston? If I could bluff him into telling me anything, it might be so much gained. I might catch him off his guard, if I could get him angry enough."

Full of this interesting idea, the submarine boy strolled slowly along to the little jail, forming his plans as he went.

Arrived at the jail, Captain Jack found the keeper, as yet, in ignorance of the dastardly attempt that had been made on the submarine boat the night before. He listened, aghast, as Benson told him the whole story.

"Now, I've got a notion that Gaston's crowd are very likely at the bottom of this whole deal," continued the submarine boy, in a low tone. "For one thing, while perhaps nothing much can be done to the other spies, this fellow, Gaston, is in here for a crime which, under the Florida laws, will go hard with him. It means that he'll be locked up for a few years. That may make both him and Lemaire ugly enough to put them up to almost any mischief. Was M. Lemaire here to see the fellow yesterday?"

"Lemaire has not been hero at all," replied the jailer.

"Was Mlle. Nadiboff here to see him yesterday?"

"No; she has been holding aloof. With the exception of his lawyer, the only people who ye been here to see Gaston were two fellows who came yesterday, about noon."

"Oho!" muttered Benson. "Who were they?"

The jailer turned to reach for a memorandum book.

"I keep the names given by all who come here to see prisoners, so I shall be able to answer you."

"Ah, here are the names. One fellow called himself Leroux, the other Stephanoulis."

"One name French, and the other Greek," muttered the submarine boy, thinking hard. "What did they look like?"

The jailer quickly and carefully described the pair. Jack listened attentively. Then rose, briskly.

"Did you hear any of the conversation they had with Gaston?"

"No."

"If they come again to-day can you lock them up and hold them?"

"If I have proper authority."

"If you get a telephone message from Mr. Trotter, would that be good enough authority?"

"Yes; on that I could hold them long enough to give Trotter a chance to come here and take them or else to get them committed on a regular warrant."

"If you keep within sound of your telephone bell, then, I think you'll have authority within a few minutes," replied Jack, briskly.

"That's a live, hustling boy," muttered the jailer, looking after young Benson through a window, as the submarine boy hurried away.

Before he had gone far, Jack encountered one of the nondescript surreys, hauled by an antiquated nag and driven by a battered darkey, that often do duty as cab in Florida. Poor as the rig was, it offered a chance of greater speed than Captain Benson could make at a walk, so he quickly engaged the rig and was driven to the place where the Secret Service men were stopping.

"You've brought us the only thing like a real clue that we have," declared Mr. Trotter, very frankly, after he had heard Jack's story. "Wait a moment, and I'll have Packwood get busy over the telephone."

Within the next twenty minutes not only had the jail been telephoned to; Packwood also talked with all the nearby railway stations in that section of the country.

"If those rascals can be found," declared Trotter, "I think we shall have gone a long way in clearing up the matter. As you say, the fellow Gaston has more reason than any of the rest of the crowd to want a complete revenge against you."

Then Mr Packwood left to walk through the little town around Spruce Beach, to see whether he could encounter any two worthies who answered to the description of Leroux and Stephanoulis.

Before half-past nine, however, word came that local constables at a little railway town a dozen miles away had arrested a couple of suspects and were bringing them to Spruce Beach. The prisoners had been taken while waiting for a north bound train, and had tickets all the way through to New York.

Then Jack hastened back to Messrs. Farnum and Pollard to report what was in the air.

"By Jupiter, Jack, I knew you had some thing strong in your mind when you left us," gasped the shipbuilder. "But I didn't imagine you'd run down the wretches as swiftly as that."

"We don't yet know that we've got the right hair," replied Captain Jack.

"I'm willing to wager money on it, if it comes to that," retorted Mr. Farnum.

Before noon the two prisoners were brought into Spruce Beach. Trotter and Packwood stopped, in a 'bus with the prisoners, to show them to Jack at the hotel.

"That pair look rascally enough to do any dirty trick," declared Jacob Farnum, in high disgust, as he looked over Leroux and Stephanoulis.

The prisoners were, indeed, "hard hooking." Both were men below average size, with sullen, defiant eyes. Both were dressed roughly, like laborers. Yet, when taken, each had been found to have a considerable sum of money about him.

"We can't make either of the fellows talk, but maybe they will later, when we begin to employ some of the third degree on them," whispered Mr. Trotter to Jack. "My boy, I think you've put us on the real trail. If the jailer identifies them as Gaston's callers of yesterday, we'll know where we stand."

Fifteen minutes later the Secret Service men returned. The jailer had pronounced the pair to be Gaston's callers of the day before. Moreover, the jailer had obligingly locked up the pair until Trotter and Packwood could obtain proper authority for him to hold them. Leroux and Stephanoulis had been placed in cells from which they could not possibly communicate with Gaston, whose cell lay in another wing of the jail.

"As soon as that pair found that, for some reason, their mine failed to explode under you last night," Trotter hinted, "they knew that their game was up. They hurried away and lay concealed in the distance. Then they saw the party from the 'Waverly' hunting on shore, with lantern's, and they took to the woods. That pair of rascals knew how risky it would be for them to try to leave at the local railway station today, so they struck off through the woods on foot making for another town at a distance. The constables who brought them down here say that Leroux and Stephanoulis were a surely astonished pair when they found themselves nabbed. We are getting into a bigger nest of trouble down here than we expected when we left Washington."

After, the Secret Service men had gone, Jacob Farnum turned as though to go inside the hotel.

"I'm wondering whether there are any letters for me," he said.

"I'll go to the office and inquire," proposed Jack Benson. At the desk he received two letters for his employer, and turned away with them in one hand when his steps were arrested by the sound of a sweet feminine voice at the further end of the desk.

The speaker was Mlle. Nadiboff.

"She looks as sweet and as contented as ever," thought the submarine boy, with some wonder. "Really, she doesn't look as though a care had crossed her path."

"Can you furnish me with a chauffeur, and order my car up?" Mlle. Nadiboff was inquiring.

"I am very sorry, Mademoiselle, but we haven't a single chauffeur that we can spare," replied the clerk, respectfully.

"Then may I rent one of your own cars, with a man to drive it?"

"Again, I am very sorry, Mademoiselle, but all the hotel cars are engaged."

The pretty Russian stamped her foot impatiently.

"Oh, no matter, then," she cried. "I will go to the garage and take out my own car. I know how to manage it."

"I regret very much to have to report, Mademoiselle," replied the clerk, speaking as respectfully as ever, "that one of the hind wheels has been removed from your car."

Mlle. Nadiboff stared at the clerk in amazement.

"Who has dared do such a thing?" she demanded, angrily.

"I am sorry, but I do not know," answered the clerk.

"Then I suppose it would be impossible, even, for me to hire one of your livery rigs?" she continued icily.

"You have guessed right, Mademoiselle."

"Oh, but this is insupportable!" cried the pretty Russian, turning away.

As she did so, she caught sight of Jack Benson for the first time.

"Oh, I would like just a word with you, my Captain," she called softly, moving after the boy, who had started toward the door.

She overtook Jack, resting a gloved hand on his sleeve.

"Do not stop," she urged, softly. "I will keep on with you, out onto the veranda."

In silence Jack stepped outside with her. Mr. Farnum had vanished for the moment, so Benson was alone with his pretty companion.

"Now, tell me, my Captain," she begged, "why it is that I cannot get either my own car, or any other conveyance, for a little drive?"

"I could only guess, Mlle. Nadiboff, and you can do that as well as I," Jack replied, gravely.

"But I desire you should guess for me, my Captain. What do you say?" she insisted, her eyes scanning his grave face.

"At the risk of seeming rude, Mademoiselle, I am not going to be prying enough to make any guesses about your affairs," Captain Benson answered, quickly.

He thought he had gotten out of the matter as cleverly as it could be done.

"Some one is taking altogether too great an interest in my affairs, my Captain. I trust you have no hand in it, for it is possible that interference with my comfort will prove dangerous to the offenders. Yet, pardon me, for I am sure that you, my Captain, would not cause me any uneasiness. Let those who do beware!"

As she let go of his arm and turned to go inside, Mlle. Nadiboff's smile was bright, almost friendly. Yet back of that smile, in her expressive eyes, lurked a look that made the boy start.

It was a look that spoke of deadly, things, and Captain Jack Benson had come quite to believe that Mlle. Nadiboff could be not only quite deadly at need, but also equally reckless.



CHAPTER XXI

A FRENCH RAT IN THE CORNER

As Mr. Farnum came around a bend in the veranda Jack hurried to him, handing over the letters. Then he related the little scene he had just witnessed in the office, and described how Mlle. Nadiboff had walked out with him.

"So the little minx was hinting at more mischief to come, was she?" demanded the shipbuilder. "Jack, I believe she's equal to it. Her crowd are anyway, if it's true that Gaston, from his cell in jail, could plan the attempt to blow the 'Benson' last night."

Hal, too, soon came up and heard. He turned anxious gaze upon his chum.

"Jack, old fellow," he pleaded, "I know you're not much given to being afraid of things. But, at least, look out for yourself a bit. Be more prudent than you usually are about yourself. That crowd of foreign spies, having failed and having brought themselves into trouble, mean to have revenge. Any of us are liable, but you'll be the shining mark of all to be picked out."

"There can't be many more of that crowd left at large," laughed Jack, lightly.

"I wonder why the Secret Service men don't arrest Lemaire and the Nadiboff young woman?" asked Mr. Pollard, the last to rejoin the little group.

"Trotter and Packwood must have some good reasons of their own," Jack replied, thoughtfully. "For one thing, they hardly have any evidence that they could use against the pair."

"They could at least drive them from Spruce Beach," retorted the inventor.

"Perhaps the Secret Service man are giving the pair enough rope for their hanging," proposed Jack.

At that moment the two detectives were espied going past in a buggy. They waved their hands to the party. Jack replied by a signal to halt. He and Hal ran down to the road to speak to the detectives.

"If it's a fair question to ask," demanded Hal, "what are you going to do with Lemaire and Mlle. Nadiboff?"

"To tell you the truth, we don't know," Trotter answered. "We haven't anything we could very well fasten on them. But of this you may be sure; our various moves are known to them, and they're on the tenterhooks of anxiety wondering what's going to break loose next. More than that, both are sharp enough to have guessed that it would be impossible for either of them to get away from Spruce Beach, now, without our leave. But we'll have to leave you, now, boys. You've been of so much help to us that I don't mind telling you what we're up to at this moment. We're driving back to jail, and we're going to try to put the screws on Leroux and his Greek companion. If we can make 'em think we've gained new evidence against 'em, they may get scared and begin to talk. If they talk fast enough, they'll begin to tell some truth."

The buggy rolled along again.

"You didn't tell them a word about Mlle. Nadiboff's threats to you," muttered Hal.

"I didn't mean to," Jack replied, simply.

"Why not?"

"Well, for one thing, I couldn't swear that she did threaten me. She may have meant it all for nonsense."

"Yes," mocked Hal Hastings. "That, would be just like her!"

The submarine not being due to go out that day, the chums decided to remain on shore, in order to keep in touch with the march of events. The day was so balmy that Mr. Farnum dropped into a chair on the porch, Pollard occupying the chair next to him. Hal, buying a magazine at the hotel news stand, sat on the edge of the porch, his feet touching the ground. Jack, his mind too full of problems to permit him to read, paced up and down the grounds. Finally he strolled, out past the gate, crossed the road and began to stroll along the shingle of bench.

Jacob Farnum removed his cigar from between his lips long enough to remark:

"As long as the lad keeps in sight, Pollard, it will be worth our while to keep an occasional eye on him."

"And when he goes out of sight—? asked the inventor, slowly.

"It will be high time to call him back. Somehow, Dave, I'm growing uneasy over the boy. I can't help the feeling that he's running into a good deal of danger that's likely to explode under him at any moment, just as that mine was intended to last night."

"It makes one feel uncanny to be at Spruce Beach," growled the inventor, savagely.

"Well, we can't run away," retorted Jacob Farnum, blandly.

"Why not, if we feel like it?"

The shipbuilder laughed.

"Why, Dave, a spirited lad like Jack Benson would be furious over anything that looked like a retreat. He'd be savage. Now, Dave, we can hardly afford to put such a slight on the boy who has had so much to do with our success."

"I suppose not," grunted Mr. Pollard, settling back in his chair.

"The odd part of it," said Farnum, presently, "is, that while we're the center of an international cyclone, so to speak, the rest of the folks at Spruce Beach don't know a word about it. Look at the crowds of folks around us who haven't even a breath of an idea of what has happened, or is, likely to happen. Not a soul around here, except our own few, have any idea that an attempt was made, last night, to blow up that mysterious-looking little submarine craft riding at her moorings out yonder."

"I wonder what the crowd would do, if it did know?" asked Pollard, gazing out curiously over the throngs of pleasure-seekers. "That shows what a dreamer you are, Dave, and how little you know of your own fellow citizens. What would the crowd do? Why, it would change itself into a mob. Mlle. Nadiboff would be hustled off out of town, Lemaire would be lynched, or mighty close to it, and it would be strange if the mob didn't march on the jail itself."

"Then it would never do to let the crowd know all that's happening, would it?" asked Pollard.

Jack, from thinking over the problems that had come up in connection with the spies, had at last let his attention wander to the crowds. Down at the beach hundreds were taking an afternoon dip. Other hundreds were strolling up and down the sands. Children were building sand castles or houses. A good many small boats were out with pleasure parties. Yet many, both grown-ups and children, looked positively bored. They needed excitement.

"How near this crowd came to having something to talk about," muttered young Benson to himself, with a smile. "If that mine had gone off last night, no one at Spruce Beach would have felt dull to-day."

Finding that the afternoon air was making him dull and inclined to gape, Captain Jack turned back from the beach. He sauntered along the road, and was about to cross it, when he heard a sharp snap. It was like a subdued shot.

In the same instant a hissing sound went pseu! in front of his face. A distinct breeze, small though it was, fanned his eyes. Then chug! Something landed in the trunk of the tree he was passing.

"That was a shot!" guessed the submarine boy, like a flash, and in the next breath he muttered: "Aimed at me, too!"

Jack pitched forward, falling upon his face. If one shot had been fired, another might be as soon as the unknown marksman realized that he had missed.

Several people, near by, fancied they had heard a shot, and turned, curiously. Then, as soon as Benson was espied lying on the ground a rush was made in his direction.

At that moment Hal Hastings happened to be looking over toward the beach. Like a flash he was up and away, his magazine falling from his lap to the ground.

"Now, what on earth has taken Hastings off like that?" demanded Mr. Farnum, looking around in surprise. "There are other people running, too. Come along, Dave!"

Hal shot his way through the rapidly gathering crowd. He reached Jack Benson just as the latter leaped up, laughing.

"Why all this excitement, just because I stubbed my toe against a dew-drop and fell?" demanded Benson, laughing.

"Weren't you shot?" gasped Hal.

"If I was, I'll make the rascal prove it," asked back Captain Jack. "But, now you mention it, I think the tree was hit."

Jack turned and looked the tree trunk over at about the height of his own head from the ground.

"See here," he remarked, laying a finger on a small perforation in the bark, "I think a bullet, or something of the sort, went in here."

"We'll soon find out then," proposed Hal, whipping out his jack-knife, opening a blade and beginning to dig. The crowd grew in size. Messrs. Farnum and Pollard had great difficulty in forcing their way through.

After some time spent in patient work Hal dug out a steel-jacketed bullet, short and of small calibre.

"You want to find the man with a weapon that bullet fits, and then make it warm for him," advised one man in the front rank of the crowd.

"Why?" queried Captain Jack, coolly, examining the missile, then dropping it carelessly into his pocket. "Some fellow fired an accidental shot, very likely, and is at this moment the most scared man at Spruce Beach. What's the use of jumping on anyone just because he had a moment of carelessness?"

"That's right, young level-head!" nodded another man, approvingly.

Messrs. Farnum and Pollard hung back somewhat. They were near enough to hear and see, and they had their instant suspicions. But the crowd knew nothing of the spy outrages, and it was not necessary to inform strangers.

So, within a few minutes the crowd broke up, straying off in quest of something more interesting. The submarine party kept on up to the hotel porch.

"That was a revengeful move, pure and simple," declared Jacob Farnum, in a low voice.

"Of course," assented Jack. "It's going to be something of a task though, to find out, for certain, just who fired that shot."

Even as the four stood there on the veranda a door opened, and M. Lemaire, faultlessly attired for an afternoon stroll, stepped out.

"Ah, good afternoon, gentlemen," was his unconcerned greeting, as he recognized the quartette.

This French spy had evidently dressed himself with a good deal of care. He carried himself with much precision and lightly twirled a natty cane.

"Pardon me, monsieur," spoke Jack, stepping forward, and looking past the Frenchman; "is that one of your friends down the road?"

As the Frenchman turned to look, young Benson swiftly and adroitly took his cane from him.

Like a flash, his eyes full of fire, Lemaire heeled about, then leaped at the young submarine captain.

But Hal Hastings stepped between them so neatly that the Frenchman collided with him instead.

"Hold this fellow a moment, please," requested Captain Jack. "I've found something interesting."

Hal Hastings grabbed Lemaire's right arm. Jacob Farnum instantly possessed himself of the other. David Pollard sprang forward so that he could take a hand, if need be.

Captain Jack stood holding the spy's walking stick, ferule end upward. It was a rather long, slender-looking ferrule of steel. But what interested young Benson most was that he had found that the ferrule was hollow.

Quickly the submarine boy examined the rest of the cane.

"Release me! Hand that stick back to me!" hissed the Frenchman. "Oh, some one shall pay for this unpardonable outrage!"

But Hal and Mr. Farnum only gripped the spy the more tightly.

"I believe I've found out something," announced Jack, in a low voice. "Wait a second or two."

He had come upon a concealed spring near the head of the cane. Stepping to the edge of the porch, the submarine boy pointed the ferrule end at the ground, then pressed upon the spring.

A sharp, though not loud report followed, and a bullet plowed into the ground. There was a flash at the end of the ferrule, though but a barely perceptible amount of smoke.

"So, M. Lemaire, you carry a pistol cane, that uses smokeless powder and shoots steel-jacketed bullets?" inquired Jack, turning to the prisoner, who, white-faced, stood gnashing hi's teeth in helpless rage. "I wonder if the bullet Hastings dug out of the tree trunk will be found to fit this weapon?"

"You miser-r-r-rable dog!" screamed Lemaire. "Thief! Liar!"

"Oh, keep cool about it, do," urged Jack, smilingly.

"What's this?" demanded Trotter, suddenly appearing on the scene. Packwood was just behind him.

Jack swiftly told what had happened, and what he had just discovered, at the same time passing the cane to the Secret Service man.

"Lemaire, I guess you'd better come with us, for safe-keeping," advised Trotter, dryly.

"You ar-r-rest me?" snarled the Frenchman.

"Oh, yes; if you insist upon a name for it."

M. Lemaire's face looked uglier than Jack had ever dreamed it possible for a man's face to look. As Hal and Farnum let go his arms the spy took a quick step toward Jack Benson.

"Stop that!" commanded Trotter, sharply, leaping to grab the spy.

"I only want to say one word to this young scamp!" hissed Lemaire. "I will not hurt him."

"You can wager he won't," added Captain Jack, clenching his fists and watching the other alertly. "Let him speak to me, if he wants."

Trotter thereupon halted, though he watched the Frenchman with lynx-like wakefulness.

Lemaire, however, merely leaned forward until he had placed his lips close to one of the young submarine captain's ears.

"See here," hissed the spy, "hold your tongue about everything, and make sure Gaston and myself are released. Else, no corner of the earth will be a safe place for you. You can find no place in the world where you will be safe from destruction—unless you get us out of this one bad fix!"



CHAPTER XXII

GALLANT, EVEN TO THE FOE!

"You may have him now," announced Captain Jack, ironically. "I reckon he has spoken his piece."

Trotter's answer was to leap upon the Frenchman, pinioning his arms behind him. Packwood snapped handcuffs over the prisoner's wrists.

"Here is the bullet that Hastings dug out of the tree—the one that was probably fired at me," added Captain Jack. "And here is M. Lemaire's cane-pistol. You can see whether the bullet fits the cane."

Trotter took them, with a swift, admiring look at Benson's cool, handsome face.

Then, guiding their prisoner, the Secret Service men moved off hastily, for two or three hundred beach walkers had just discovered that something exciting had happened, and were hurrying forward.

Lemaire was forced into the buggy and driven rapidly away. Once out of sight the Secret Service men turned, driving straight for the local jail.

Before anyone in the excited crowd could ask what had happened the submarine people had vanished.

These four hurried to a room that Mr. Farnum had reserved while they remained at Spruce Beach.

"What was it that rascally Frenchman whispered to you?" demanded the shipbuilder.

Jack promptly repeated the threat, whereat Mr. Farnum's face grew decidedly grave.

"The worst of it is, Jack, I think the fellow not only meant the threat, but has the connections necessary to carry it out," said the ship builder, slowly. "I am quite prepared to believe that these spies work in large groups, when necessary. I am beginning to think that it will be wise move to get you way from here—in time."

"That would give Gaston a fine chance to go clear," retorted young Benson. "I am a very important witness when his case comes up."

"You are also a very important young man for our submarine company," replied Jacob Farnum, "so important, in fact, that I don't want to have you put out of this world through any of their plots for revenge."

"But don't you see, sir, that, if I run away from here, the fellow Gaston is very likely to be liberated?"

"Let him go, then," urged Mr. Farnum, though it was plain that he spoke reluctantly.

"It's just what I won't do, sir. I wouldn't be a good citizen if I should allow a criminal to escape justice just because I was, afraid to stay and testify against him," argued Captain Jack.

"I admit the force of all you say," assented Mr. Farnum, slowly. "Yet, if I should find, after thinking it all over, that it will be best to instruct you to leave here quietly, you won't refuse to obey, will you?"

"Yes," declared Jack Benson.

"What? It would be the first time you ever balked at orders, then."

"But this is different, Mr. Farnum. I refuse to obey any order that will tend to defeat the ends of justice."

Jacob Farnum winced at that statement of the matter. He had been anxious only to save Jack from the attempts of a dangerous crowd.

"Jack is right," broke in David Pollard, decisively.

"When he puts the case in that way, I don't dare say that he isn't," admitted the shipbuilder. "At the same time, I can't bear the thought of the lad being butchered to gratify the grudge of any of the rascally crew that we've offended here at Spruce Beach."

A slight, rustling sound at the door caused them all to wheel about. Jacob Farnum's eyes beheld a slip of white paper lying on the floor, just inside the door. Jack Benson saw it, also, but he sprang past the paper, pulling the door open.

Around a turn in the corridor the submarine boy heard the sound of fleet footsteps.

Jack pursued, but could find no one, and the sound of moving feet had also ceased. As soon as he was satisfied that he could not catch the prowler, the submarine boy returned to the room.

"Do you see this?" asked the shipbuilder, holding out the slip of paper.

"Another warning, I suppose?" Benson ventured.

"Yes; and it shows that you are being followed and watched. Something worse is almost certain yet to happen."

Jack took the slip of paper, reading these printed words:

"You have been fairly warned. Are you going to be a fool? Obey, or—"

That was all. The meaning of the words was plain enough, but Jack, with as cool a smile as ever, folded the slip, dropping it in one of his pockets.

"This will interest Trotter," he remarked.

"There is no use whatever in advising you, suppose?" asked the shipbuilder.

"If these threats were directed against you, would you cringe from them?" demanded the young submarine captain.

"Of course I wouldn't," replied Farnum, a sudden flash lighting his eyes as he spoke.

"Then why should you expect to see me turn coward?"

"I won't say another word about it, Jack!" replied the shipbuilder, gripping his captain's hand. "I have dreaded to see you go down under the mysterious assaults of these scoundrels. I have hated to see a boy come to that harm while serving me. But I realize, now, that it would hurt you worse to run away than it would to stay and face any kind of punishment or even death itself."

"That's the talk, sir," nodded Hal. "And no one is going to harm him, either. There are too many of us—if we keep our eyes open."

That "if" covered a wide field of possibilities. Not one of them could foresee all that the ingenuity of the enemy would provide in the way of danger.

To quiet his own agitation Jacob Farnum had recourse to a cigar. He lighted it, smoking with a very solemn look on his face.

"What's all the excitement, I wonder?" muttered Hal, presently.

The distant sound of running feet, then cries came to their ears, though none in the little party could distinguish the words.

"There's some big excitement on. Come along," urged Jack, reaching for his cap.

"Humph! We've had excitement enough to last reasonable people for a long time," grumbled the shipbuilder, but he, too, sprang for his hat.

Ere they had run far through the corridor they encountered other guests fleeing.

"What's the matter?" called Jack.

"Fire in the south wing," called back one man. "We don't know, yet, whether the hotel is doomed."

Just then the fire alarm bell of the hotel began to sound loudly in all the corridors.

That brought the remaining guests on the run, some appearing not completely dressed.

As the rushing throng began to thicken at a door on the ground floor the sound of a whistled of clanging gongs was heard without. The Spruce Beach fire department was responding to the alarm.

Captain Jack bounded out. Hal kept close at his chum's heels while Messrs. Farnum and Pollard came along less fleetly.

Through half a dozen windows on the second floor of the south wing flames now leaped, while the smoke curled up in dense clouds. This wing was built wholly of wood, and was doomed, even though the rest of the hotel could be saved.

Jack halted, at last, Hal bumping into him.

Some of the firemen were hauling hose from a cart, while others were attaching an end of one length to a fireplug. A hook and ladder truck was hauled to the scene, its crew standing by ready at need.

Whish! Two four-inch streams struck the flames, yet seemed only to feed them to greater fury.

"We can't put that blaze out, men!" roared the local fire chief. "Turn the streams against the main building and stop the blaze from spreading. Let the axe crew follow me!"

Swiftly a couple of long ladders were unlimbered and placed close to the main building. The fire chief and his men scaled these with agility and tried to fight their way into the rear of the blaze.

Jack stood scanning the windows on the third floor, just above the present belt of fire. Then, through one of the windows on the upper floor he saw a sudden red glow thrust its way.

"The fire is eating through to the top," he turned to explain to Messrs. Farnum and Pollard, who had just reached the boys.

"I think they'll save the main building, however," returned Mr. Farnum, as the ringing sound of ax-blows reached them and the heavy streams of water were carried after the wielders of the axes.

"I hope everybody is out, up there in the wing," uttered Hal, glancing in that direction.

As if in answer a window was suddenly raised with frantic haste.

A face, a figure appeared there, framed by the sill and sides. Then a red tongue of flame shot up in the background, illumining the face of a terrified woman.

"Why, it's Mlle. Nadiboff!" gasped Jack Benson.

The pretty Russian shouted down appealingly, though her words were drowned by the crackling of the blaze and the lusty strokes of the fire fighters.

"Quick! We must get a ladder up there!" shouted Jack, turning back to the truck. "We can't let a human being be burned before our eyes."

But there were no firemen at hand. They had followed their chief. Hundreds of citizens stood about, but they needed a leader.

"Come on, men!" roared Jack. "Help me off with this longest ladder."

A dozen pair of hands reached for it at once. Off came the ladder with a bound, while other men pressed up to aid.

"Right up to the sill of the window where that woman is!" shouted young Captain Benson. Up went the ladder, exactly in place, while a score of voices shouted:

"Get out on the ladder and come down, young lady! Can you?"

As if in answer, Mlle. Nadiboff was seen suddenly to reel backward as though overcome by the smoke that poured up at her from the floor below.

"Where are you going?" shouted Jacob Farnum, hoarsely, as the submarine captain threw off his jacket like a flash.

"Up there—of course—to help her!" Jack shouted back at him, as he leaped at the rungs.

"It's the only thing a man can do," admitted Farnum, hoarsely. "Good luck to you, Jack!"



CHAPTER XXIII

"GOOD-BYE, MY CAPTAIN!"

The first part of the climb was easy.

Unmindful of the cheers that followed the submarine boy raced up the ladder.

Then he struck the belt of heavy smoke. Flames, too, leaped out at him. He went through that zone of red with all possible speed, yet swift as he was, he felt as though he were being roasted.

Then, at a greater height, the boy was forced to close his mouth, barely breathing, for the smoke surrounded him. He felt as though he were stifling, but he kept on.

Up on the sill the watching crowd below saw him. Then Jack Benson leaped inside.

Ah! He could breathe, here, just a bit more, though the smoke had followed him.

At the further end of the room, by the door that opened upon the corridor, the flames were eating their way up through from the floor below. There was a red barrier there that shut off any hope of retreat by the corridor.

Yet these things Jack Benson saw only as his gaze swiftly swept the room.

Mlle. Nadiboff lay in an unmoving, unconscious heap on the floor, some ten feet back from the window. She was in evening dress, as though prepared to descend to dinner.

"She can't go through the line of fire in that rig," muttered Jack, even while his head reeled from the weight of smoke on his lungs.

Furiously he sprang at the bed, snatching off the blankets. These he threw on the floor, rolling the Russian woman up in them.

Then he bent over to lift her. Ordinarily he could have performed the task with ease, for his young arms were strong. But now, three-quarters strangled by the smoke he had inhaled, Jack fairly tottered, with the insensible human form in his arms, back to the window:

As he stepped out upon the ladder Jack vaguely heard the cheers that volleyed up at him.

To most of those below it looked as though he were moving easily. But Hal, waiting on the rungs of the ladder, just below the fearful belt of smoke and flames, saw differently at a glance.

Holding firmly to his burden, Jack started down carefully, but as swiftly as his quaking knees would permit.

"Come along! Steady with you!" bellowed up Hal Hastings, as he fought his way up to his chum.

An instant later Hal growled out

"Let her go. I have her—safe!"

Hal was just above the smoke belt, and his own head was reeling, now. Tongues of flame leaped out at them all. Speed alone could save them from one of the most painful of deaths.

Down through the belt they moved. As they neared the ground willing hands reached out to catch them.

"Pull those blankets off the girl! They're afire," shouted one man, and was obeyed. Mlle. Nadiboff, after the blankets had been stripped away, was carried off, still unconscious though safe as far as fire was concerned.

The clothing of both the submarine boys had caught and was smouldering. Both Jack and Hal submitted to being thrown on the ground and rolled until the last spark had been extinguished.

"Bring milk—a lot of it, for these young men," ordered a physician who stood in the crowd. For Jack and Hal, on their feet again, leaned almost helplessly against Farnum and Pollard. Their lungs were so filled with smoke that both boys felt as though they could never breathe again.

When the milk was brought, however, and forced down their throats under the doctor's orders, they found that this somewhat oily fluid brought back a good deal of the missing power to breathe. After a while both boys began to move about again. Yet both felt a strange feeling of oppression and weakness.

"For the rest, your feelings will simply have to wear off," the physician told them. "You'll be all right in time. And it was a fine, manly piece of work that you both did."

After nearly an hour of stubborn work the firemen saved the main building, though that southern wing was practically destroyed.

When the danger was over hotel discipline asserted itself once more. News was passed that the belated dinner was ready, and the lately excited guests filed in for their meal, though many complained of a loss of appetite.

Neither Jack nor Hal felt like eating then. They sat by Messrs. Farnum and Pollard, though the submarine boys contented themselves with sipping more milk.

"That was one way of answering the enemy's threats," laughed the shipbuilder, in an undertone.

"We don't know that Mlle. Nadiboff was in any way connected with the threats," replied Jack, in an equally low tone.

"She belongs in the enemy's ranks," observed David Pollard, dryly.

As the quartette were leaving the table one of the negro waiters stepped up to them.

"De lady dat was brought down outah de fiah done wanter see Marse Benson in de parlor," announced the waiter.

"Mlle. Nadiboff?" inquired Mr. Farnum. "Then I guess we had all better go in Jack, I'm going to keep you in my sight."

As they entered the parlor the submarine people saw three or four women standing about a sofa on which lay the pretty Russian.

At sight of the newcomers the Russian signed to the attendants of her own sex to raise her, and then to withdraw. Jack went forward to the sofa, his friends taking seats on the opposite side of the room.

"Pardon my not rising, my Captain," begged Mlle. Nadiboff, as Jack Benson left his friends to go forward and greet her. "I find I have not my full strength yet."

Since she offered her hand, Jack, under the circumstances, took it simply, then released it. He stood before her in the uniform that had suffered in the fire.

"I am told that you, my Captain, nearly lost your own life in saving my less than worthless one," continued the Russian woman. "It was a strange thing for you to—considering. Will you believe me when I tell you that I greatly respect your courage and your manhood?"

"Yes," bowed Jack. "Though it was nothing but a sailor's easy trick."

"You would make little of it, would you, my Captain?" smiled Mlle. Nadiboff, plaintively. "True, you risked much for a life that has been worth but little. Still, I sent for you to do more than assure you of my appreciation of your generosity."

As she spoke, the young woman thrust one hand into the bosom of her dress. She drew out a little envelope which she held in her hand for a few moments.

"You have been threatened, my Captain?" she whispered, looking up at him.

"Oh, ye-es," assented Captain Jack Benson, shrugging his shoulders.

"And by very desperate people."

"So far," smiled the boy, "they have injured only themselves."

"Yet you do not know how far their vengeance can reach."

"Nor shall I lose any sleep thinking over it," Captain Jack replied, looking down at her with his baffling smile.

"Your enemies had one trick prepared for you," whispered the Russian, "that you might have found it hard to meet."

"Yes?"

"Of course you do not suspect it, but we have even one of the waiters here—a worthless, reckless black—in our pay."

"It may have been he who thrust the paper under our door before—before the fire?" ventured Jack.

"It was," nodded Mlle. Nadiboff, seriously. "And it was the same waiter who, on receiving this envelope from me, would have mixed the contents with the next cup of coffee served you in the dining room of this hotel. But I am overcome by your generosity, my Captain. Take this envelope—and do not place what it contains in your coffee."

Though Jack Benson may have started inwardly, his hand did not tremble in the least as he reached out and took the envelope, which he dropped into one of his pockets.

"Thank you, Mademoiselle," he said, simply.

"There is nothing about me, my Captain, that you can admire," spoke the Russian woman, sadly. "I have not led the right kind of life. But I have just that grain of good in me that enables me to admire one as fine and manly as I have found you to be. You have given me my life—a worthless one, at best. So I give you your life—and may you make as splendid use of it as you have started out to do. And now, good-bye, my Captain. You cannot continue to know such as I."

Despite what he knew of this dangerous woman, Jack Benson felt himself touched.

"What is going to become of you, Mademoiselle?" he asked. "Will you be dragged down in the snares that have entrapped your confederates!"

"I do not know. How could I know?" she asked, looking quickly up at him. "Yet, if my accomplices escape, and find that I have served you, my Captain, do you know the forfeit they will exact?"

"Your life?" whispered Benson.

"Yes!"

"Then, if I can, I am going to help you to escape them," promised the submarine boy. "Yet that can happen only on your most solemn word—given, pardon me, in a moment of absolute honesty—that you will never again play the spy, for the secrets of the United States Government."

"Oh, I will promise that," replied Mlle. Nadiboff, quickly. "Yet I hardly need to. After what I have done, just now, no one in my peculiar line of work would ever trust me again. I shall be shunned, hereafter, if not destroyed, by those who have worked with me."

"I shall do my best to get you safely away from Spruce Beach," promised Jack Benson. "Have you more to say to me, Mademoiselle?"

"Nothing, but good-bye, my Captain."

She held out her hand. Once more Jack took it, bending low over it. Tears shone in her eyes, but Jack did not see them, for he turned, going back to his friends.

Not until they were well away from the parlor did Jack Benson offer any account of the interview that had just taken place.

"Let me have that envelope, then," requested Jacob Farnum, gravely.

"What are you going to do with it, sir?" Jack asked, as he passed it over.

"Do with it?" repeated his employer. "I'm going to take it to the nearest druggist, and find out what the stuff is."

"We'd better take this latest news to our friend Trotter," suggested David Pollard.

"By all means," nodded Farnum. "And I'll meet the rest of you there."

The little house wherein the Secret Service, men had taken up their headquarters was not far away. When the inventor and the submarine boys rang the bell Mr. Packwood admitted them.

"Step right into the next room," advised Mr. Packwood. "You'll find some one there you know."

A the submarine folks entered the room they saw Trotter seated at a table on which were writing materials. At the other side of the table standing very erect, and in a very respectful pose, was the Japanese, Kamanako.



CHAPTER XXIV

CONCLUSION

"Good evening, honorable gentlemen," said the Japanese, turning when he heard the new arrivals entering.

"Mr. Kamanako is going to leave us," announced Trotter, with a smile. "He goes north to-night. Here is the slip of paper, my boy, that will take you past any meddlesome inquiry. But it is good only until midnight, so I advise you to be sure to catch to-night's express."

"I shall, and thank you, honorable sir," replied the Japanese, bowing.

"Then I won't detain you any longer, or you may miss your train."

Once more the Japanese bowed, then turned to Captain Jack Benson.

"Honorable Captain," he said, "I had pleasure to show you something about jiu-jitsu. You did me honor to show me most excellent thing you called American strategy. I shall not forget it."

With bows to the others Kamanako quickly took his leave.

"We had nothing very strong on which we could hold that fellow, so we had to let him go," declared Mr. Trotter, after the outer door had closed. Then he added, with a sigh: "That's the worst of catching spies, under such laws as we have in this country. Rarely are we able to punish them as they deserve."

"He won't come back, will he?" asked Jack.

"Not for a while, anyway. We have made the fellow nervous, and he will give us a wide berth for a considerable time."

"Why don't you hit all these people the hardest kind of a blow?" demanded young Benson.

"I wish I knew how to," sighed Trotter.

"Then spoil them with too much publicity," proposed the submarine captain. "Let the whole country know all about them and their records, and just how they look."

"If I could! But how am I to do it?"

"Why, there's a writer here at Spruce Beach," Jack continued; "a man named Hennessy. Let him write all the facts of this whole story, or such of the facts as you want made public. Let Hennessy have the photographs of this spy crew. He can print the yarn in his newspaper and in some magazine, and can use all the photos. Then these people will find themselves so well known that about all of them value as spies will be gone."

"By Jove, but that's a clear-headed idea," muttered Trotter, rising from his chair. "It will do the trick, too. Where is this man, Hennessy?"

"Stopping at the Clayton, sir."

"Packwood, will you go over and get that reporter?" asked Mr. Trotter, turning to his associate.

In the next minute Jack was telling Trotter of the fire-incident and the envelope that Mlle. Nadiboff had given him. By the time the submarine boy had finished his recital Jacob Farnum hurried in.

"That stuff," he reported, "is morphine sulphate, and the druggist says there was enough of it to take you clear out of this world and into the next."

"Hm! That Nadiboff woman!" muttered Trotter. "She has been as dangerous as any of them, and yet it is hard to be rough with her after her one act of gratitude to you, Benson. I could see that she went north on the train, of course, but she'd be liable to suspicion and punishment by some of the members of the gang of that infernal Gaston. He has yet other men, I suspect, who may be watching the trains further on, and Mlle. Nadiboff, after saving you, Benson, from their latest death trap, might run right into their vengeance. She ought to be gotten away from here by some other means."

"She can be—by ship," hinted Jack, quietly.

"Let me see," mused Trotter. "Yes; that can be done, if you want to take some trouble. At about eleven to-night the Savannah freight steamer, bound for Havana, will pass by about a dozen miles out. You could pick her up by watching for her searchlight. Do you feel like sending Nadiboff to Cuba, in that fashion?"

"If it suits her, we'll do it," Jack replied quickly enough.

"It may be very bad for her if it doesn't suit her," replied Trotter, grimly. "Well, hurry along and see if you can do it. Drummond and Miss Peddensen are going north to-night, also."

As the submarine party left the house they met Packwood and Hennessy coming along.

"I think you'll get as good a news story as you can want to-night," said Jack to the reporter. "You remember, Mr. Farnum promised you one before the tip was given to any other reporter."

Hennessy expressed his, thanks warmly, and the quartette hastened on to the hotel. Captain Jack had little difficulty in seeing Mlle. Nadiboff in the parlor. When he explained to her the plan, she gladly accepted.

"You will not believe me, my Captain," she smiled, wearily, "but I am wholly through with spying. I shall never again disgrace my womanhood in that way."

Owing to the fire Mlle. Nadiboff was not burdened with baggage. She carried her evening dress in a new dress suit case bought by Hal at one of the stores. In going away she wore a plain gray dress and dark brown jacket purchased from one of the maids at the hotel. Mlle. Nadiboff's jewelry and money, with which she was well supplied, had been in the hotel safe, so that she left with the means of pursuing her journey in comfort.

"It is a whim of mine, my Captain," cried the Russian, gayly, as they left the hotel, "but will you give me your arm down to the shore?"

"Gladly," Jack agreed.

They took a shore boat and went out to the "Benson." While Captain Jack helped the pretty visitor aboard Hal hastened below to bring her up a chair.

"You have your wish, at last, Mademoiselle, to visit this craft," Jack laughed, then added, gravely: "I am sorry, indeed, that I cannot invite you below."

"I have lost my desire to see the interior of the boat," she replied, with equal gravity.

A start was made in plenty of time. Gayly the "Benson" bounded out over the waves, as though even that grim little steel craft of war could appreciate the fact that its dangers were over.

In time Captain Jack picked up the Havana bound freighter by the rays of her searchlight, and moved on out to intercept her. He signaled that he had a passenger to put aboard. The steamship lay to, lowering a side gangway, and the "Benson" ran neatly in. The transfer was made.

Just as she was helped over the side Mlle. Nadiboff placed her hand in Jack's.

"Good-bye, my Captain," she said, sadly.

"Good-bye, Mademoiselle," answered the submarine boy. "And remember that you are done with the spies."

"Forever! Again, good-bye, my Captain."

As both craft moved off on their respective courses Captain Benson saw a little white handkerchief fluttering at the freighter's stern rail. As long as it could be visible over the waters that handkerchief fluttered. "I guess the little Russian must have tied her handkerchief there," observed Eph, dryly, and Captain Jack smiled; while Jacob Farnum turned to whisper to the inventor:

"Dave, our youthful captain has the greatest respect in the world for a woman, but he'll never be made a fool of by one of the wrong kind."

Henceforth, as long as she remained at Spruce Beach, the submarine craft was wholly unmolested and avoided by spies. Gaston, who turned out to be the real leader of one party, instead of M. Lemaire, was sentenced to prison for assault. Leroux and his Greek accomplice confessed to the attempt to explode the mine under the "Benson," and were sent to the penitentiary. There, also, journeyed M. Lemaire, for a long term, on account of his all but successful shot at Jack Benson.

With the exception of those sent to prison none of the spies have as yet been heard from.

For a considerable time the "Benson" remained at, or near, Spruce Beach. Hennessy's articles attracted great attention to the craft. The Navy people were charmed by the new capabilities shown by this latest of the Pollard submarine boats.

Later the submarine boys were destined to turn their attention to new and thrilling work with submarine craft And now came most stirring times that put their grit, intelligence and resource to the hardest kind of tests.

These newest happenings will be related in full in the next volume of this series, which will appear under the title: "The Submarine Boys' Lightning Cruise; Or, The Young Kings of the Deep." The reader of this new volume will find a rare treat in store for him!

THE END