[riffic]

> going back to the 19th century

18th, even. From the same Wikipedia article you shared:

> The Postal Inspection Service has the oldest origins of any federal law enforcement agency in the United States. It traces its roots back to 1772 when colonial Postmaster General Benjamin Franklin first appointed a "surveyor" to regulate and audit the mails. Thus, the Service's origins—in part—predate the Declaration of Independence, and therefore the United States itself.