All the members of Dick & Co. were now in full retreat. They
were courageous lads, but, with the immediate landscape in seeming
danger of blowing up, getting away was the wisest possible course.

"Say, what do you make of that?" demanded Greg breathlessly, when
the Grammar School boys had halted, well out of sight of the cottage
and down in the woods.

"Bang!" replied Tom dryly. "That's all I heard."

"And blood," almost chattered Hazelton.

"But what it means is a big puzzle," Dick added. "If Rip and
his crowd are or were in the cottage, they would hardly explode
anything purposely and perhaps kill a man. That man appeared
to be dead---he must be dead. Rip and Dodge are mean fellows,
but they're hardly up to killing people."

"There was an explosion," remarked Tom judicially, though his
voice was still husky. "Now, while I don't know everything, I
believe there always has to be an explosive in order to bring
about an explosion. Am I right?"

"You stand on ground that no one can dispute," nodded Dick. "But
how did the explosive come to be in a building that belongs to
the water company, and which is supposed not to have been occupied
in some years?"

"What was the man doing in there, for that matter?" demanded Tom.