This was the situation, then, when submarine D-16 set forth from London, to do, with her new power, what damage she could to the enemy’s fleet.
One day, while the lads had been looking over the vessel, as she lay in drydock, they had seen a man run furtively from the place as they approached; but they were unable to catch him. A second time they had seen him, though not close enough to identify him.
Although both had thought considerably of the matter, neither had mentioned it to the other, and it had been allowed to drop. Nor had they come upon the man again before they put to sea.
The sinking of the German vessel related in the first chapter had been the first venture of the D-16, and now the vessel was heading toward the coast of England again, having gone as far toward the strong fortress of Heligoland as Lord Hastings had deemed advisable at that time.
All day the little vessel continued on her way, traveling upon the surface, for there was now no need to submerge. She went very slowly, and night found her not many miles from the scene of her first encounter.
A sharp lookout was kept for some sign of an enemy, but there was none.
With the coming of the first light of day, Jack and Frank ascended the bridge together, and turned their eyes toward the west. A faint cloud of smoke on the horizon gave evidence of a ship of some sort.
“Probably a British vessel,” said Jack.
“Can’t tell,” returned Frank. “A German cruiser may have succeeded in running the blockade and getting in behind.”
“That’s true, too,” Jack agreed. “It’s a mystery to me how they do it. England is supposed to have them safely bottled up. It’s beyond me how they get out.”