"The fellow who visited us," George argued, "was light and quick on his feet. This bum detective waddles a lot like an old cow."
"Then we've passed the boy who called to see us, and failed to leave a card," grinned Will. "We may meet him as we return!"
"Here's hoping we bump straight into him if we do meet him," George exclaimed. "I'm just aching to get my hands on that fellow!"
"I'm not particularly anxious to catch him just yet," Will suggested. "I want to find out what the kids are up to before we pounce down upon them."
While the boys stood in the passage, whispering together, the light moved on until it came to a chamber which seemed to be rather shallow, for the reflection of the searchlight was still in the gangway.
"Now we've got him!" exclaimed Will. "I think I remember that chamber, and, unless I'm very much mistaken, it opens only onto this passage! While he's poking around in there, we'll sneak up and see what's he's doing!"
Before the boys reached the entrance to the chamber they heard the sounds of a pick. When they came nearer and looked in they saw the detective poking away at heap of "gob" which lay in one corner of the excavation. He worked industriously, and apparently without fear of discovery. Now and then he stooped down to peer into a crevice in the wall, but soon went on again.
"I wonder if he thinks he can find two boys in that heap of refuse?" laughed George. "I wonder why he don't use a microscope."
The detective busied himself at the heap of refuse for a considerable length of time, and then began further Investigation of little breaks in the wall. Using his pick to enlarge the openings he made a systematic search of one break after another.
"Looks like he might be hunting after some pirate treasure," George chuckled. "I never heard of Captain Kidd sailing over into the sloughs of Pennsylvania. Did you?"