miked.18145
  Junior Editor

I have some old Corning and 1 KOPP glass lens.. I have a couple groups of letters I would like know meaning of. These include the follwing strings 1. "D.S. RDL (on a 1935 lens). #2 Corning lens and initials are " D.F. RDL." #3 Corning lens 1935 all by itself on the same raised lip that all the writing is there is a lone letter "g". wondering what means. On a 1935 Corning Lens after the made in the usa approximately 1.5 inches there is just a letter "B". On the same lens it sz 5" DIA F.R......what does the F.R. stand for??? Sorry for all the questions.......my railroad person couldnt tell me. Thanks more »