Lith printing is one of those "where does it go" processes. It's not a lost process from the dark ages of photography. It is simply a neat way of printing an image. The basic idea is to use an extremely diluted developer with an extended developing time. The image appears with what is known as infectious development - the dark areas develop faster than the rest of the image. Black and white paper can end up with nice colors and some wildly graphic images. Lith is one of those processes that ,done once, is constantly whispering in the back of your mind.