Rob H.,
I found this image on the web:
http://robinsonsantiques.com/picture-nails-hooks/picture-hooks-1-4.htm#hooks1
Sent email to the nice folks at Roninson's Antiques, here is their response:
>begin reply<
They were just intended to keep both sides of the wire close together in the
center as you put the loop over the center (top) hooks. This would (at least
in theory) keep the frame always straight as it could not slide easily.
Watch "new arrivals" for the latest updates to the site.
If you need immediate assistance call. The shop is open Sun-Tues & Thur-Fri
9-5 eastern time
Always Call Ahead for appointment before coming out
We are closed Wed & Sat but Open 24/7 on the net.
Steve
RobinsonsAntiques.com
763 West Bippley Road
Lake Odessa, MI. 48849
Phone 616 374-7750
http://www.RobinsonsAntiques.com
>end reply<
As always, thanks for the interesting photos,
Kerry