“Great work, Mr. Beatty!” shouted Dave hoarsely, as another three-inch shell struck the enemy, this time at the waterline. “Mr. Curtin, half speed ahead!”

As the destroyer began to lose headway and slowly circle the undersea boat, the “Logan’s” crew cheered, this time without rebuke from the bridge. The submarine craft was rapidly filling and sinking.

At a safe distance Darrin watched, for he was humane enough to wish to rescue the German survivors, should there be any. So swift was the sinking of the enemy, however, that there was no time for them to launch and man the collapsible lifeboat that they undoubtedly carried.

Then the seas closed over the hated craft. A few moments later Lieutenant-Commander Darrin gave the order to steam forward slowly, the watch standing by to discover and heave lines to any swimmers there might be afloat. Not a head was seen, however. Three men at the after gun had been observed to jump before the submarine went down, but no trace of them could now be found.

“We’ll never know how many hundreds of decent lives the work of the last minute has saved,” declared Dalzell hoarsely as he reported on the bridge.

“Find out as promptly as possible what damage we have suffered,” Dave ordered. “We were struck several times.”

As Dan saluted and hurried away, Darrin picked up his night glass and once more resumed his scanning of the sea. Lieutenant Curtin had already received orders that the destroyer was to cruise slowly back and forth over and around the spot where the submarine had gone down.

“It seems almost wasted sympathy to try to pick up enemy survivors,” muttered Mr. Curtin rather savagely.

“But it’s humanity just the same,” Darrin returned. “And Americans must practise it.”

“Of course, sir.”

Dalzell, who had summoned the aid of other officers and some of the warrant officers, soon returned.

“Two breaches, one just above water line, and the other below it, sir,” was Dan’s beginning of the report. “I wasn’t aware that a torpedo touched us. If it did, it made a dent, but glanced off without the explosion that a direct hit would have produced. That may account for the dent below the water line. But a shell hit us above water line. Is it possible that a large fragment glanced low enough to make the dent under water? It doesn’t seem possible.”

“Not likely,” smiled Darrin.

“The hole above the water line has been repaired, but men are still working at the one below the line,” Dalzell went on, “and the pumps are working hard. The chief engineer was about to report it to you when I reached him. We have been hit at other points, but no serious damage has been done.”

“We are not in danger of sinking?”

“Doesn’t look like it to me, sir,” Dan replied, “and the chief engineer is of the same opinion.”

“Take the bridge with Mr. Curtin.”

Not more than two minutes was Dave below decks, half of that time with the chief engineer. Then he hurried back, disappearing into the radio room. In a code message he notified destroyer headquarters of the encounter, its result, and the nature of the damage to the “Logan.”

Within five minutes the answer came back through the air:

“Return to repair. Keep alert for enemy craft understood to be more numerous in your waters than usual.”

The order bore the signature of Admiral Speare’s flag-lieutenant.

“Home, James,” smiled Darrin, after reading the order.

So the “Logan” was put about. Dave did not steam fast, for it had been found impossible wholly to stop the hole below water line. Water still came in, though in diminished quantity. Fast speed would be likely to spring the damaged plates.

It was near dawn when land was sighted, and the sun was well up when the “Logan” steamed limpingly into port. Half an hour later American dock authorities had taken charge of the destroyer. Dave waited until he saw his beloved craft in dry dock and the water receding from under her as it was pumped out of the basin in which the “Logan” now lay.

In the meantime Dalzell, who had had two hours’ sleep on the way to port, was busy granting shore leave to such men of the crew as were entitled to have it. More than half of the officers also received leave.

As soon as luncheon had been finished, and after Darrin had conferred with the dock officer, he and Dan went ashore.

“Where shall we go?” asked Dan, when they had left the naval yard behind them.

“Anywhere that fancy takes us,” Darrin answered, “and by dark, of course, to a hotel for as good a shore dinner as war times permit.”

“We’d have a better dinner on board,” laughed Dan, sometimes known in the service as Danny Grin. “These British hotels are all feeling the effects of the enemy’s submarine campaign, and can’t put up a half-way good meal.”

Once in the streets of the port town, the two young American naval officers strolled slowly along. The crowds had a distinctly war-time appearance. Hundreds of British and American jackies and two or three score French naval seamen were to be seen.

“Whoever invented saluting doesn’t have my unqualified gratitude,” grumbled Danny Grin. “My arm is aching now from returning so many salutes.”

“It’s a trifling woe,” Darrin assured him. “Look more sharply, Dan. You missed those two French sailors who saluted you.”

Too good a service man to do a thing like that without regret, Dalzell turned around to discover that the two slighted French sailors were glancing backward. He wheeled completely around, bringing his right hand smartly up to his cap visor and inclining his head forward. Facing forward once more he was just in time to “catch” and return the salutes of three British jackies.

“Quite a bore, isn’t it?” asked a drawling, friendly voice, as the two young officers paused to look in at a shop window’s display.

The young man who had hailed them was attired in a suit and coat of quite distinctly American cut. He was good-looking, agreeable in manner, and possessed of an air of distinction.

“The salute is a matter of discipline, not of opinion,” Dave Darrin answered, pleasantly. “It isn’t as troublesome as it looks.”

“I have sometimes wondered if you didn’t find it tedious,” continued the stranger.

“Sometimes,” Dave admitted, with a nod. “But it shouldn’t be.”

“You are an American, aren’t you?” asked Dalzell.

“Yes. Matthews is my name. I’m over here on what appears to be the foolish mission of trying to buy a lot of fine Irish linen, and that is a commodity which seems to have disappeared from the market.”

Somehow, it didn’t seem quite easy to escape introducing themselves, so Dan performed that office for the naval pair. Darrin would rather not have met strangers in the port that was the destroyer base. Mr. Matthews walked along with them, and presently it developed that he was staying at the hotel where Dave and Dan had decided to dine. So, after an hour’s stroll, the three turned toward the hotel.

“I’ll see you later,” declared Matthews, affably, starting for the elevator on his way to his room.

“Dan,” said Darrin, laying a kindly arm on his chum’s coat-sleeve and speaking in a low voice, “I’d just as soon you wouldn’t introduce us to chance acquaintances.”

“That struck me afterwards,” Dalzell admitted, soberly. “Yet, for once, I do not believe that my bad habit of friendliness with strangers has done any harm. Matthews appears to be all right.”

“I hope he is,” Dave answered.

Later Matthews joined them below.

“It struck me, gentlemen,” he declared, “that my introduction was rather informal. Permit me to offer you my card.”

He tendered to each a bit of pasteboard that neither could very well decline. It was a business card that he had offered, and its legend stated that Matthews was connected with a well-known Chicago dry-goods house.

“But in these times,” smiled their new acquaintance, “an American passport is a better introduction than a mere card.”

Whereupon he produced his passport. After a glance at it the two young naval officers did not see how they could escape offering their own cards, which Matthews gladly accepted and deposited in his own card-case.

He did not intrude, however, but soon moved off, after a cheery word of parting. Dave and Dan went out for another stroll, returning in time for dinner.

Hardly had they seated themselves when Matthews, fresh and smiling, stopped at their table in the dining room.

“I’m afraid you’ll vote me a bore,” he apologized, “but American company is such a treat in this town that I’m going to inquire whether my presence would be distasteful. If not, may I dine with you?”

“Be seated, by all means,” Darrin responded, with as much heartiness as he could summon.

When the soup had been taken away and fish set before them, Matthews asked:

“Don’t you find the patrol work a dreadful bore?”

“It’s often monotonous,” Dave agreed, “but there are some exciting moments that atone for the dulness of many of the hours.”

“And frightfully dangerous work,” Matthews suggested.

“Fighting, I believe, has never been entirely separated from danger,” retorted Dalzell, with a grin.

“Have you sunk anything lately?”

Both naval officers appeared to be too busy with their fish to hear the question.

Matthews looked astonished for only a moment. Then he waited until they were half through with the roast before he inquired:

“How do you like the work of the depth bombs? Are they as useful as it was believed they would be?”

Dave Darrin glanced up quickly. There was no glint of hostility in his eyes. He smiled, and his voice was agreeable as he rejoined:

“Now, I know you will not really expect an answer to that question, Mr. Matthews. The officers and men of the service are under orders not to discuss naval matters with those not in the service.”

“P-p-pardon me, won’t you?” stammered Matthews, a flush appearing under either temple.

“Certainly,” Dave agreed. “Men not in the service do not readily comprehend how necessary it is for Navy men not to discuss their work, especially in war-time.”

Matthews soon changed the subject. After they had gone forth from the dining room he shook hands with them cordially, and took his leave.

“Is he genuine?” asked Dalzell.

“Must be,” Dave replied. “His passport was in form. You know how it is with civilians, Danny-boy. Knowing themselves to be decent and loyal, they cannot understand why service men cannot take them at their own valuation.”

Just as the two were going out for another stroll the double doors flew briskly open to admit a group of more than a dozen British naval officers.

“Hullo, there, Darrin! I say there, Dalzell!”

Surrounded by Britain’s naval officers, our two Americans had to undergo almost an ordeal of handshaking in the lobby.

“But I thought you were far out on the water, Chetwynd,” Dave remarked to one of the officers.

“And so I was, but a bad break in a shaft sent me in,” grumbled the commander of an English destroyer. “Beastly luck! And I was needed out there,” he added, in a whisper, “for the Germans are attempting a big drive underseas. We’ve new information, Darrin, that they’ve more than twice the usual number of submersibles loose in these waters.”

“I’ve been told the same,” Dave nodded, quietly.

“What brought you in?”

“Shell hits, I think they were, though one dent might have been made by a torpedo,” Darrin answered.

“Then you had a fight.”

“A short one.”

“And the German pest?”

“Went to the bottom. I know, for we saw her sink, and her conning tower was so damaged that she couldn’t have kept the water out, once she went under. Besides, we found the surface of the water covered with oil.”

“I’ll wager you did,” agreed Chetwynd, heartily. “You Yankee sailors have sunk dozens of the pests.”

“And hope to sink scores more,” Darrin assured him.

“Oh, you’ll do it,” came the confident answer. “But come on upstairs with us. We’ve a private parlor and a piano, and plan a jolly hour or two.”

From one end of the room, in a lull in the singing, an exasperated English voice rose on the air.

“What I can’t understand,” the speaker cried, “is that the enemy appear to have every facility for getting the latest gossip right out of this port. And they know every time that a liner, a freighter or a warship sails from this port. There is some spy service on shore that communicates with the German submarine commanders.”

“I’d like to catch one of the rascally spies!” Dan uttered to a young English officer.

“What would you do with him?” bantered the other.

“Cook him!” retorted Dan, vengefully. “I don’t know in just what form; probably fricassee him.”

Little did Dalzell dream how soon the answer to the spy problem would come to him.