This colorful set is one in a series of 24 cards issued by the BELL BAKERIES INC.. One was inserted into each package of their brand of BELL SUPERSOFT BREAD. I believe that this series is the series is designated as series D39-7 in Burdick's American Card Catalogue and is entitled "NATURAL SPLENDORS OF AMERICA" Burdick does not provide a date for this series but I believe it to have been issued in mid to late 1940's. Each card features a beautifully illustrated image of one of America's Natural Wonders, on the front signed by the Artist Charles Rosner, well know for his illustrations for many publications and advertising work in the 1930’s and 40’s. Bread card collectors will be familiar with his work on many different American bread card series. The back provides instructions to send away for a ALBUM to paste these cards into. It also states that "One Picture is wrapped in every loaf of Bell Supersoft bread".