Just as the sun was setting, the lofty needle-like pinnacle of the Wolf Lighthouse was observed, rising above the horizon and backed by the vivid crimson of the disappearing orb of day.
There was little or no wind. The surface of the sea was as placid as a mill-pond, broken only by the bow-wave of the two vessels. So calm was the air that the savoury smell from the galley of the merchant vessel was wafted to the nostrils of the officers on the bridge of the destroyer. On the lofty fore-deck a seaman was about to hoist the steaming-lamp. His figure silhouetted against the ruddy light was, when viewed from the destroyer, just clear of one end of the bridge.
For no apparent reason Terence kept his glasses focussed on the man, who, awaiting the order to send the light aloft, was taking a farewell view of the rapidly-receding coast-line of Old England, for the Cornish hills were just visible abaft on the starboard quarter.
Suddenly the fellow put the lamp on deck and shouted. Although Aubyn heard no sound, he could distinctly see the seaman's mouth working as he pointed to something on the starboard hand. Then heeling heavily to port the "Syntax" circled in the direction indicated.
"A submarine, by Jove!" ejaculated Terence. "On the tramp's starboard bow—and the old man's trying to ram her."
Gilroy, too, levelled his glass, but owing to the glare on the water he could pick up no sign of the submarine. But Terence was right in his surmise. A periscope had emerged from beneath the surface at less than a cable's length from the "Syntax." The courageous old skipper had put his helm hard a-port, with the laudable intention of ramming and sending the submarine to the bottom.
He missed; more, the hull of the cargo steamer screened the submarine from the destroyer's bow-gun.
"That's done it!" ejaculated Gilroy, as a column of water tore skywards on the far side of the luckless vessel. The merchantman heeled violently, recovered herself with a corresponding roll, as her main-mast buckled, burst its shrouds and toppled across the deck.
"Full speed ahead!"
The engine-room telegraph gong had scarce ceased vibrating ere the "Livingstone" leapt ahead like a greyhound released from its leash. With the oil-fired engines running at their utmost capacity the destroyer quickly circled round the doomed vessel, but not a sign of the modern pirate was to be seen. Having shot the cowardly bolt, the submarine had quickly dived, and perhaps was lying en perdu eighty feet beneath the surface.