by Franklin W. Dixon
The third Hardy Boys mystery begins with the boys being duped by a stranger at the rail station. They change a large bill for him, which turns out to be counterfeit. In the revised edition the brothers would never be so daft, so it was their chubby chum Chet who takes the fall. Counterfeiting, the...
This one was pretty unremarkable except for the interesting scenes at the secret factory/lab building. I really enjoyed those. I also really, really want a false wall in my room.
I think the Hardy Boy books helped me with learning deductive and inductive skills. I had to work through logic. Who knew? I enjoyed all these books.