"I guess that's the best plan," admitted Ned.
"Perhaps we could learn something more of the men who were in the house," suggested Fenn.
"How?"
"By going down there and making inquiries. I know those buildings. There's a watchman hired to stay on guard all night. Perhaps he saw the men and could tell us who they were."
"It's a good idea," said Ned. "We'll go down and see him to-morrow night. That will be Sunday, and there's not likely to be any one around to hear us question him."
"We must not take Frank along," remarked Bart. "We'll have to keep this thing quiet from him, at least until we know more about it."
"It's the first time we haven't all been in a thing together," commented Ned. "It seems queer to have something on Frank doesn't know about."
"We're doing the best we know how," said Bart. "It's for Frank's interest we're working. I hope it will all come out right."
Sunday evening the three chums went to the building where Ned had been taken by the Upside Down boys. Frank had not called on any of his chums since the dinner the night before.
The boys found the night watchman, who had just come on duty. Ned knew him, for the man, James Rafferty, had once been employed as a porter in the bank of which Ned's father was cashier.