What I didn't have was any of the actual daily records of his life in the Secret Service -- if there was newspaper coverage of arrests and investigations, there must be more details. I also have wondered why would someone who in all the decades in the US census was selling insurance or bonds or working as a clerk would have decided to become an Operative for the Secret Service?
The actual records from the National Archives might answer some questions.
Oh how revealing those records turned out to be!
One letter, dated 28 November 1906 from the Chief, thanks Harry for information sent to the Secret Service,
BUT "in the hope we may be able to see you down here later on" and is addressed "dear Dicky"
This sounds like John Wilkie, the Chief of the Secret Service, already knows Harry Bogart Richardson.