Here is a wonderfully glazed strain I got from the Yankee Pole Cat's recent On Golden Pond show. It is marked with an unmistakable Pennsylvania keystone and what I think is "41893."
Does anyone have any more information on this?
Update: With the help of Elton Gish and Matt Grayson, this peice has been identified as likely being produced by Franklin Porcelain and distributed by the E.S.S. Co from between 1906 and sometime in the 1920s.
A little further research by myself would have turned up this very similar piece which is in Caleb Thimell's collection:
I am glad to see that both the 41892 and 41893 styles have turned up.
Thanks Elton and Matt!