I believe this was used for a food product (based on its shape) and that late 19th century is correct date-wise.
If it were not for the "A," I would say this was a product of the JR Watkins company which has been around long enough (and still is in business) but the "JR" is short for Joseph R... so the mystery continues.
I do not find an A. Watkins mentioned in Ketchups, Pickles and Sauces nor is the mark mentioned in either of my two manufacturer references.