People in the past were as interested in how the world worked as we are. Authors and illustrated produced works to cater to that interest — including an incredibly bizarre "flap book" that shows what human insides look like. Now you can look at the whole thing online. In 1613 Johann Remmelin published a book, Catoptrum Microcosmicum, which became a best-seller for about 150 years. Today, Columbia University published it online. The work, originally in Latin, was translated into several languages. It explained the human body, using movable flaps to take people down through successive layers. The first layer was the person delicately draped in a way that preserved their modesty. The layer of drapery came off first.
After that, Remmelin went under the skin.
This is a 1661 edition, which needed a little work before it could be scanned. The archivists at Columbia had to undo some damage to the book, as several pages had a dark stain that made it difficult to read, and also made the flaps brittle.
They lightened the stain by moistening the pages and applying a suction device to lift away some of the stain particles. Other damage they left alone. Clearly, they decided not to do anything about the female figure's resplendent moustache.
The book features a female figure and a male figure, both shown from the front and the back. Each figure is drawn with one foot standing on a skull. As you can see in the picture above, the book isn't short on Bible allusions. The skull has a snake going through it and an apple branch next to it.
Get a little closer, though, and the dissected skull just looks like Krang from Teenage Mutant Ninja Turtles.
In addition to the regular male and female figures, the book takes us inside a pregnant female torso. As you can see in the gif above, it's the creepiest experience imaginable — made worse by the fact that for an unexplained reason, we get a shot of what can only be termed a crotch-demon before we delve deeper into the anatomy.
Check out the full text, if you dare, here.