he attention of Schwalbe and his crew was centred upon the battleship;
the Kapitan momentarily expecting to see the huge vessel reel under the
impact of the terrible torpedo, while the men began to entertain grave
doubts as to whether the British ship would accept their token of
surrender. The fact that the super-Dreadnought showed no signs of
slowing down revived Kapitan Schwalbe's doubts. Knowing the difficulty
of hitting, even at a comparatively short range, a swiftly moving
target, he began to wonder whether he did the right thing in falling in
with von Hoffner's diabolical plan.

His hurried thoughts were suddenly interrupted by some light object
enveloping his head and shoulders. Before he could tear the fabric
away he heard two distinct splashes, followed by shouts of astonishment
from the crew; for with one clean sweep with his knife Ross had severed
the halliards of the ensign staff.

The lads dived deep, swimming the while with long, powerful strokes,
for both were accomplished in the art of natation. They were longer in
coming to the surface than they anticipated, owing to the weight of
their half-boots, which they had been unable to remove without risk of
causing suspicion.

When at length their heads emerged almost simultaneously, they found
themselves nearly fifteen yards from the doomed U75.

"Strike out!" spluttered Ross. "Get as far away from her as you can.
Never mind about old Schwalbe. He can't hurt us."

Ross was right, for however much the Kapitan wanted to wreak his
vengeance upon his former prisoners, he was unable to do so. In his
role as that of an officer waiting to surrender, the possession of a
revolver would tend to "give the show away". He had left his pistol in
his cabin--an example that his Unter-leutnant had followed. And now
his attention was directed upon the British battleship.

Meanwhile, the lads, swimming strongly, saw the _Tremendous_ heel as
she ported helm. For a minute, not knowing how a ship behaves when the
helm is suddenly put hard over, they thought that the treacherous
unterseeboot had successfully carried out her cold-blooded plan. Yet
no explosion occurred, and the battleship recovered her normal trim.

With their eyes only a few inches above the surface, the lads could see
nothing of the track of the torpedoes. They had no indication that
they had been fired until the _Tremendous_ let fly with her 12-pounders.

"I think we've saved her," said Vernon