The second floor door to a modern day restaurant. In medieval times the structure could have been any type of food establishment or shop. Anything needing to be stored would have been hauled up by rope and wenches to this upper floor, or loft.
Now does this shot below give you any ideas? Hint: look at the copper part. What do you know about copper and brass and buildings?
Hint # 2: look at the copper pipe going into the wall of the building. What goes into a building only in copper pipes? Further hint: it used be delivered into buildings via lead pipes. Until we realized that that delivery system could cause neurological damage.
Still a thingamajig? This set of copper pipes with a brass mechanism delivers water. This whole section of dirt next to the driveway of a 100 year old apartment building spent the entire weekend dug up right through the sidewalk and into the street. At night there would be boards over the trench. By this morning? Voilá! Shiny new copper pipes with a brass regulator. I’m quite sure the residents of the building are glad that they have a new, useful, thingamajig delivering water.