Even as he fumbled with the sliding locks a terrific roar rent the air. Where the destroyer had been but a brief instant before there was nothing but a cloud of smoke and a shower of flying debris, while, at an altitude of about five hundred feet and rocking violently in the agitated air, was a large flying-boat.
"Hang on to the bag, Moke," exclaimed Farrar. "'We needn't scuttle it now. Hullo, here's Little Willie."
The last remark referred to the coxswain of the patrol boat. More fortunate than his former messmates he was floating upon the surface at a distance of less than twenty yards from the sub and his companion. Not only had he lashed a lifebelt round his waist but others encircled each leg. A fourth he grasped with his left hand, while his right arm was waving frantically to attract the attention of the aircraft that had strafed a vessel flying the ensign under which he served.
"Wonder if it's the 'Avenger'?" soliloquised the sub. "Shouldn't be surprised, but they are all so beautifully alike. Can't tell t'other from which."
He was not long left in doubt. The flyingboat circled above the scene of her latest success; then spotting the immersed men, she shut off her motors and glided gracefully downwards, alighting with a healthy splash at a distance of nearly half a mile from the sub and his companions.
Then the motors throbbed again, and under the action of her hydrostatic propeller the flying-boat glided on the surface towards the spot where the patrol craft had foundered.
"By Jove!" ejaculated the sub. "We're in luck's way. It is the 'Avenger,' and there's old Barcroft, bless his chirpy figurehead!"
"Who's Barcroft?" inquired the Moke.
"Pal of mine, and a thundering good sort," replied Farrar. "Don't let that portmanteau go now."
"I don't mean to," declared Sylvester grimly. The "Avenger" eased down. Maintaining a precarious hold on her flaring sides a bluejacket "stood by" with a coil of rope.