I have received some emails requesting the size of the drumhead. The overall diameter is 25” and the image diameter is 23 1/2”. I will be adding a post to this string of a drawing that will show more detail of the backside of the drumhead. We think the drumhead was originally made from a modified version of an old oil lit drumhead. The best we can tell it was always electric as the San Juan drumhead on the Rio Grande.
The most interesting feature is the image appears to be an old Chromo-lithe material, which is similar to a large slide. This “slide” has been filled in with paint or color. This would explain the damage. Also as Sam March mentioned earlier the image appears to be a mirror image of the West Needle Mountains which would explain the mirror image as well.
Bill Lund