"Is that fake detective part of his gang?" said Bob. "He's the one who blew him up."
"I don't know," exclaimed Hugh in despair. "We just go 'round and 'round in circles and don't seem to get anywhere at all."
"But the fact remains, doesn't it, boys," inquired Mr. Cook, "that whether we know who the gang is, and what the relations are between the two gangs—if there are two—that somebody is hard at work plotting against this country? Also they are becoming bolder for they know that their time is short; sooner or later they are bound to be caught."
"You're afraid for your factory to-night, aren't you, father?" asked Bob.
"I am, indeed," said Mr. Cook.
Bob was on the point of asking if he and Hugh might not help guard it when the telephone rang and his father was called away to answer it.
CHAPTER XVIII
KARL HOFFMANN
"Let's go down and talk to Heinrich," exclaimed Bob when his father left the room.
"Aren't you going to ask your father if we can stand guard to-night?"