I have a mystery object that someone thought important enough for three
patent dates, so I hope someone here will recognize it.

It's a black disk about 1" diameter of hard synthetic material. One side
has a flat ring and then is convex with a small metal disk on the middle
with a "15" engraved on it. The flat ring has four little holes making a
square, but they don't go all the way through. It also has raised print
reading "PAT'D/Aug 15, 1916/Feb 27, 1917/June 22, 1920/OTHERS PENDING"

The other side has a matching ring and concave section. At the center of
the depression is a small metal post. The flat ring has two small posts
(that don't line up with the holes on the other side).

I can send a scan of the side with writing to anyone who's interested.

Thanks!

Carol
--
Carol A. Nickolai

Anthropology
University of Pennsylvania
email: [log in to unmask]
voicemail: 215-751-8989, 0077#