Swimming, the boys could plainly follow its flight. As the Undaunted swung out of the way to avoid it they could see that the missile had a clear path to the Sylph.
With a gasp the boys saw the torpedo speed toward the little scout cruiser. Lord Hastings had not seen the projectile launched—because a view of the German ship had been obstructed until the Undaunted swung out of the way—and no effort was made to avoid it.
The torpedo crashed into the Sylph on the water line, and the explosion which followed must have torn through all the various compartments to the engine room, for there was a second loud explosion, steam leaped up on all sides of the Sylph, and when it had cleared away, there was no Sylph to be seen.
The little scout cruiser had disappeared; vanished, had been destroyed.
Of Lord Hastings and the other officers and men, the lads could see nothing.
For a moment the boys were unable to speak, so astounded were they at the suddenness of this terrible disaster.
"Great Scott!" gasped Frank at last. "Do you realize what has happened?"
Jack was more calm.
"Perfectly," he replied faintly, with a sob in his voice. "The Sylph has gone, and with her Lord Hastings and all on board—all our friends, the only ones we have in the world."
The two boys unconsciously swam closer together.