During lunch the wireless room reported that a vessel was sending out calls for urgent aid, and in response to a request for further details came the startling news that the Dutch liner, "Noord Brabant," had been forcibly boarded by the crew of the "Vorwartz" fifteen miles due east of Wadi Jemel. Several of the Dutchmen had been wounded when attempting to resist; the strong-room had been forced, and nearly ten thousand pounds worth of gold had been removed. Not satisfied with this, Karl von Harburg discharged a torpedo at the ill-fated "Noord Brabant," which, exploding under her starboard quarter, completely flooded the after compartments. Leaking badly, for the shock had strained the water-tight bulkheads, the liner headed slowly for Sherm Sheikh, an inlet in the mainland, where her captain hoped to run her aground on the mud and sand that form the bottom of the cove.
"Here we are," exclaimed Captain Restronguet, running his finger over the chart of the Red Sea. "Ninety miles from Wadi Jemel; three hours run at our maximum speed. Keep her going for all she's worth, Kenwyn. I'll be with you in the conning-tower in less than ten minutes. Let the 'Noord Brabant' know we're on our way, and keep me informed of how she's progressing."
While the "Aphrodite" tore on her errand of mercy, Carclew was keeping vigilant watch upon the electric detector; but, to the disgust of all on board, instead of the "Vorwartz" making her presence felt more strongly the sensitive current grew more and more feeble. Was it possible, then, that the "Vorwartz" was able to attain a much greater speed than her rival, and in consequence slipping farther and farther from the doggedly-pursuing avenger?
Just as Captain Restronguet, accompanied by his guest, was about to proceed to the conning-tower, a final message came from the ill-fated "Noord Brabant"--"Sinking; are taking to the boats."
But the "Aphrodite" was not the only vessel hurrying to the rescue. The P. & O. Liner, "Persia," a magnificent internal-combustion propelled ship of 40,000 tons, that had been built to "knock spots off" the largest North German Lloyd boat on the Australian route, was returning on her maiden voyage. Warnings of the presence of the "Vorwartz" had been given her. Her cargo was a precious one; moreover she carried His Majesty's mails; but at the urgent call of distress all other considerations were set aside.
The officers of the "Persia" knew the risks they were running. It was recognized that Karl von Harburg would not attempt to attack or intercept the liner unless the "Vorwartz" were submerged, consequently the speed of the submarine would then be considerably lower than that of the liner. The "Persia" being a subsidized vessel under the recent Admiralty regulations, had a large percentage of Royal Naval Reserve officers and men in her crew; she was armed with light, quick-firing guns, and, in fact, was a powerful "protected" cruiser.
Owing to the danger the captain and the first officer were both on the "Persia's" bridge. Elaborate precautions had been taken to keep the news from the passengers, but, as is frequently the case, the intelligence was soon common property. That night no one went to bed; since it was within the bounds of possibility that in the event of being torpedoed by the ruthless "Vorwartz" it would be necessary to take to the boats. All lights were carefully screened; yet in spite of these preparations the "Persia" had the narrowest escape in her career.
Unseen and unheard by the officers of the watch, a torpedo discharged from the lurking "Vorwartz" glided within ten feet of her rudder. Just at daybreak the "Aphrodite" sighted the boats of the ill-fated "Noord Brabant." Towed by two motor pinnaces the life-boats, crowded with passengers, were slowly making their way northward. The "Aphrodite" had arrived in the very nick of time, for the sudden change from intense darkness to daybreak revealed the fact that three suspicious-looking Arab dhows were making ready to pounce down upon the unarmed boats.
"Red Sea pirates, by Jove!" exclaimed Captain Restronguet.
"Certainly looks like it, sir," replied the sub. "It's a curious fact, but our cruisers systematically search every little harbour on the Arabian coast and find nothing beyond a few dhows owned by Arab traders whose papers are quite in order. But once let a vessel go ashore or get into difficulties, armed dhows, manned by cut-throat Arabs, gather round like flies about a honey-pot. Goodness only knows where they come from."