The Public Domain review is an outstanding resource, collecting some of the most fascinating and entertaining pieces of art that have fallen out of copyright’s legal restrictions. This website is full of treasures.
One of my personal favorites is this children’s book by Charles Bennett, where a cat exhausts his nine lives. It is charming and macabre, back when children’s books were permitted a macabre streak. The rhymes are cute but it’s the illustrations that make it. The cat ghost at the end, oh my.