If it helps at all...
Here are a couple articles that may help shed light on the "Jesse James Proof" saying
http://www.antiqueguns.biz/guns/cannonball%20safe.htm
http://www.ottawaherald.com/story/061408cannonball

This short article (http://www.richmondfed.biz/about_us/our_tours/money_museum/v...) says they were in use from the 1890s to 1920s. I found online that the Farmers and Merchants Bank was founded in 1906.

Though a tedious article to read through if you aren't interested in iron man competitions/weight lifting, there are some interesting facts about the type of safe (the smaller version of it, anyway) here, too:
www.la84foundation.org/SportsLibrary/IGH/IGH0603/IGH0603m.pd...

There is actually a lock museum...maybe they could help, too, in explaining the history of that type of safe and the advertising of it and such. http://www.lockmuseum.com/about.htm
or this early office museum:
http://www.earlyofficemuseum.com/