Beneath the surface
There are some historical achievements that we still marvel at today. How was it that people who hadn’t invented the automobile managed to build the Great Pyramids? Without clockwork, how did the Mayans make accurate calendars? What’s Stonehenge all about?
I do feel for this questioner. He’s seen all this art from the Middle Ages and wants to know how his ancestors could paint such detailed skeletons if they didn’t have our modern technology to do x-rays? Yes, it seems that he forgot about skeletons.