Belle Isle Zoo postcards

"Looking at the postcards themselves, they are all believed to be issued from a range of 1930-1945. They are 3½ x 5 inches from the Tichnor Brothers Collection, at the Boston Public Library. They used a linen texture, which indicates why they’re dated 1930-1945, as this is the linen period for postcard making. This period was highlighted by a new process being used and spread by Curt Teich & Co. , which printed its first linen card in 1931. This is why the postcard has a high rag content, like it was made from linen instead of paper. Furthermore it explains the amount of these postcards (because the process made producing them much quicker) along with the vibrant colors in them compared to earlier postcards, as this process also made it possible to use brighter dyes. This also tells us that the color itself is due to someone using dyes to color on the postcards after they had been produced, since photo color was not possible yet, meaning that all these postcards are hand colored. It also explains the white border along the photos, which most postcards retained (it’s hard to see with a white background but the border is there)." —Uncovering the Abandoned Belle Isle Zoo: A look at the History of the Belle Isle Zoo and the Artifacts it Left Behind (see attached student research paper).