Wow, met one Yancy Smith at latest South Philly Type-IN. Next thing I know–a bundle of typewritten questions lands on my desk. Not sure if he needs to quiz more typosphereans, but his email is: smity701@newschool.edu . Well, must get back to this — some hard ones, like: “To you, what defines your collection?”
phillytyper 
I’m not sure I could quickly provide the answers to all of the queries I can read in that photo! You’ve got your hands full.
One note: I’d recommend, for the sake of your readers, that you change the destination of your link to “Davis Typewriter Works” to the present address for ongoing work, videos, and historical research which we are still doing all these years later. http://davistypewriters.blogspot.com/