And just as the seller described, there was the imprint on the bell top:
Finding the patent turned out to be easier than I had expected. When I plugged in the issue date of March 6, 1923 and the word "Dow" for an assignee, patent number 1,447,397 popped right up:
A name as unusual as "Vierling" begged for a little more digging to see what else I could find (searching a name as common as "O’Brien" isn’t as likely to produce results). And I found another Vierling from Minneapolis who was a prolific inventor of mechanical pencils from the 1920s through the Second World War: Frank J. Vierling. Frank’s patents were assigned to a number of companies, including Brown & Bigelow (the firm that produced the Redipoint, later Ingersoll Redipoint) and even Autopoint.
But Frank did something really interesting shortly after April 6, 1921, the date on which Mary, who I’m assuming was his wife, sister or some other relation, applied for the patent for her pencil. Check out patent number 1,531,427, which he applied for on June 14, 1922:
And number 1,693,099, which he applied for on June 3, 1926:
All four of these Frank Vierling patents have something in common with each other, but not with anything else Vierling invented: they are all essentially minor variations on Mary Vierling and Elizabeth O’Brien’s basic design!
Whatever the relationship was between Frank and Mary, history leaves me with the distinct impression that it drove Frank up the wall that Mary patented and sold the rights to her patent for a pencil. You know what they say . . .
hell hath no fury like a man scorned!