I looked at the frame and the photos again. I think I can barely discern the WD below what I thought was JH, but again, I agree it could be JD. One more favor. Would you concur that the date is c. 1900?
It is 1900.
If you poke a but of damp cloth in the mark and wiggle it, the tops of the letters should become clean leaving the background black. This will help you make it out.
Miles and Tom: Thanks for your input. I used a q-tip and cleaned it some more. I was able to make out the "JD" and see the "D" under the upper "D"; however the other letter is covered by a nail. I checked under the Chester and found nothing.