Being 6'7" I've learned the hard way that there is a difference between standard door heights in the U.S. and Europe. When I stand straight under a standard door in the U.S. my hair just brushes the top of the door jamb, which is 80" high. Years ago I periodically travelled to the U.K. and Germany for work and found myself ducking under typical interior doorways. I have since learned the standard door height over there is 78". One time as I was exiting a bathroom stall I forgot to fully duck under the steel door frame and scalped the top of my head, drawing a little blood, which was both embarrassing and painful!
Many old (over 200 years) European doors are significantly shorter than 78". I can only imagine how many people bumped there heads as the population's average height increased.
About the art:
I created this using Inkscape and tried to emulate those old two color technical graphics from the 50's and 60's. I found Inkscape to be very clunky to use compared to Illustrator for this. Some of this is due to having much more training in Illustrator. I do like the calligraphy tool better in Inkscape, which I used to draw the figure.
I was trying to make another illustration involving the bathroom stall in the same manner but ran out of time trying to figure out the best combination of Inkscape, Illustrator and Photoshop to use. In the future I'll stick to drawing with real ink and converting to vector art. Drawing straight into vector format just doesn't come as natural to me.