service with the Boy Scouts had done so much
to develop. It was comparatively easy for him to follow the course he
had planned, and he knew that with every step they were getting further
from the heart of Semlin and nearer the boathouse which was his
destination. There was every reason to suppose, too, that he would not
have to handle Hallo single-handed much longer. Behind him, when he
glanced back from time to time, the trail was plainly marked by the
little scatterings of corn.

"I'm glad it's night time," he reflected, with a grin. "In daylight
there would be birds after that corn, and it wouldn't serve as a trail
for very long. But it's good fun; it's like a paper chase, or hare and
hounds. Only this time the hare wants to be caught!"

Then he thought of Hallo, and decided that at least one of the hares
wasn't anxious to be caught at all.

"Still he doesn't know what I'm doing, I guess," thought Dick, "There's
no use in spoiling the pleasure of this little walk for him by telling
him, either. He'll know soon enough, if I have any luck."

They were in open country by this time, with very few houses in sight.
Suddenly Hallo broke out.

"Where are you taking me?" he cried, fearfully.

"Oh, you're beginning to recognize the route now, are you? Yes, we're
going back to the place you came away from in such a hurry not so very
long ago!"

"You were there!" said Hallo; suddenly, "I thought I knew your voice--in
the boathouse! That was you who came in the launch?"

"I don't have to answer," said Dick. "Hurry along! You slow up when you
talk. And your talk isn't interesting enough to make it worth while to
delay."

"I--"

Whatever Hallo meant to say was never finished. For suddenly the ground
shook, and there was a dreadful roar. A huge flash lit up the sky, and
behind them bedlam seemed to break loose. There was a succession of
reports, like repeated volleys of rifle fire, and sometimes a louder
roar.

"There goes the arsenal, so you can quit worrying," said Dick. "Even if
I let you go now, you couldn't prevent that, could you? Oh, I knew what
you were driving at, all the time!"

CHAPTER XV

THE TABLES TURNED

But even Dick, for all the wild mood of anger that had held him since he
had had Hallo in his power, had to consent to a halt now. If the
Servians planned not only to inflict a severe blow on the Austrians by
the destruction of war material, but to spread terror as well, they
succeeded adm