Stirling, when the three chums had retired to the cabin.

"That they had to be very careful," replied Denbigh. "That I don't doubt. I'll give them a week at the very outside. If we are not free men then, I reckon we're booked to Davy Jones his locker."

The cabin was plainly furnished. An electric light was burning, but the porthole had been previously closed and locked. Overhead an electric fan was buzzing, while fresh air was admitted by means of ventilation pipes communicating with the open air.

"We might do worse," remarked O'Hara as he proceeded to undress. "The rotten part of it is, we can't see what's going on outside. The beggars have cooped us up pretty well."

"They are evidently busy," said Stirling, as the bustling of some hundreds of men was plainly audible above the hum of the fan. "Perhaps they do the worst of their dirty work during the hours of darkness."

The three officers proceeded to make an examination of their quarters. The walls were of pitch-pine, but upon O'Hara sacrificing one of his razors, it was found that the woodwork merely formed a casing to a thin steel bulkhead. The ceiling, too, was of steel, coated with a patent cement to preserve the metal and to prevent "sweating". The door was of steel, and was fitted with a "jalousie" or latticed shutter; but their captors had taken the precaution of bolting a solid metal plate over the opening.

"Not much chance for anyone who happens to be a somnambulist," said Denbigh. "Well, it's no use kicking against the pricks when you're barefooted. I'm going to turn in. By Jove, I do feel horribly sleepy."

"And so do I," added Stirling, unable to stifle a terrific yawn.

"I believe I'm asleep already," muttered O'Hara drowsily.

A moment later the three chums were lost in oblivion. An opiate secretly administered by the doctor had been mixed with their food. So soundly did they sleep that they were unaware of a terrific crash that took place during the middle watch—the explosion of a torpedo launched from the supposed Dutch liner at a large French vessel.

Von Riesser had risked an example of frightfulness. The huge, heavily-charged missile—powerful enough to sink the largest battleship afloat within a couple of hours from the moment of impact—had literally torn to pieces the lightly-built hull of its victim. Before the luckless passengers and crew rushed for the boats—and these were for the most part shattered—the French craft sunk like a stone.

It was not until the sun was almost overhead that Pat O'Hara awoke. The deadlight of the porthole had been unshipped and the cabin was flooded with dazzling sunlight.

He sat up in his bunk. His head seemed to be splitting. Everything in view was slowly moving to and fro with a semicircular motion.

"What the deuce have I been up to?" he soliloquized. "Where was I last night? By Jove, I must have had another touch of that rotten malaria."

Presently the erratic movements of his surroundings quieted down. He became aware that Denbigh and Stirling, lying in their bunks on the other side of the cabin, were still sleeping and breathing stertorously.

"Now how in the name of goodness did those fellows get into my cabin?" asked the puzzled Irishman, for he was under the impression that he was on board the Nichi Maru. "Has someone been having a rag?"

From the alley-way came the sound of voices. He listened. The speakers were making use of a foreign language. It was not the soft, pleasing Japanese tongue—something harsh and guttural.

"German!" ejaculated O'Hara. "By my blessed namesake I remember it all now."

He leapt from his bunk and, crossing the cabin, shook Denbigh by the shoulders. The Sub's only reply was a grunt of semi-conscious expostulation. O'Hara turned his attentions to the Scot.

"Fore!" muttered Stirling, engrossed in the joys of a round of golf in dreamland.

"More like twelve, be jabbers," retorted O'Hara. "The sun's well over the fore-yard. Show a leg and shine, you lazy bounder."

The discipline imbued in the old Dartmouth College was too strong to resist the nautical invitation to get up. Stirling rolled from his bunk—fortunately it was the underneath one—and subsided heavily upon the floor.

"Pull yourself together, man," counselled O'Hara. "Those rotten Huns have been hocussing our grub."

"If they have, they have," muttered the imperturbable Stirling. "That's no reason why you should bellow into my ear like a ninety-thousand horse-power siren."

Leaving the Sub huddled upon the floor O'Hara proceeded to dress.

Suddenly he exclaimed:

"The dirty spalpeens! They've been to my pockets while I was asleep."

This announcement literally electrified his companion, for Stirling remembered that he had over twenty pounds in Australian sovereigns in his purse. Alas! The gold had vanished.

"Your pistol?" asked Stirling.

The Irishman whipped his uniform cap from a hat-peg.

"It's there," he reported. "And might you be wanting it to let daylight into the fellow who collared your cash?"

"Not much use without cartridges," replied Stirling savagely. "It might have got us into hot water if they had found it. Better pitch it through the port-hole, old man, before it lands you in queer street."

"No fear," declared O'Hara. "It may come in handy some day."

Some time elapsed before the two men were able to rouse Denbigh from his stupor. He, too, discovered that a small amount of gold that he happened to have on him at the time of the capture of the Nichi Maru had been taken from him. Some silver and a few Japanese coins had been left.

"We've been drugged right enough," said Denbigh. "I wonder why? There's some underhand game afoot during the hours of darkness. To-night we'll do without wine at dinner, and see how that acts."

Having completed their toilet the three Subs left the cabin, for the door was now unlocked and the metal covering to the jalousie removed. Without stood a seaman on sentry duty. He drew himself up stiffly as the British officers passed, but made no salute, nor did he attempt to bar their progress.

At the foot of the companion-ladder a petty-officer stopped them.

"Breakfast awaits you in this cabin," he said in German. Neither Stirling nor O'Hara understood, while Denbigh was sufficiently on his guard to feign ignorance of the nature of the announcement.

"Der vos a meal for you in dere," announced von Langer, stepping from behind the shaft of a ventilator.

"Thank you!" replied the three Subs in unison.

"But it's nearly lunch time, isn't it?" added O'Hara.

"Dey vos tell me der Englische are very fond of sleep," retorted von Langer with a laugh. "Himmel! I tink dot is very true."

The meal over, the prisoners went on deck. Out of curiosity Denbigh walked to the rail and leant over the side. He was not surprised at what he saw. The ship's sides had been painted during the night. The black band still remained, but the yellow paint had been replaced with a coat of blue. Already the tropical sun was blistering the still wet paint, revealing patches of the original hue underneath. The funnels, too, had been redecorated. They were now red with black tops.

Some minutes later Kapitan von Riesser descended from the bridge and walked aft. Seeing the British officer he crossed the deck.

"You like our new colour scheme?" he asked.

Denbigh did not reply to the question. He asked another.

"Mr. Stirling and I both lost some gold during the night. Our cabin was entered while we were asleep and the money taken from our pockets. Was the—er—theft committed at your instigation?"

For a moment von Riesser hesitated.

"There was no theft," he replied. "The gold was taken from you prisoners——"

"Contrary to——" began Stirling hotly.

"In accordance with my instructions," continued the Kapitan. "Gold is of no use to you. Instead, you will be furnished with Notes to its equivalent as