Staring at the Walls

I'm literally staring at the walls, and I'm confused by what I see.

This is a close-up of the painted fabric wall in my room. As I said earlier, this type of wall covering appears in a few places around the house. I assume that it's original, meaning it dates back to 1893. If not, then it's probably from the big remodel the Hart family did in the 1930's. Either way, it's a lot older than me.

It's a bit hard to see in this photo, but there's a discolored area in the middle of this part of the fabric wall covering. It's rectangular and runs left to right. Some of the cracks in the paint roughly follow the borders of the discolored area.

My hunch is that there used to be a shelf mounted to the wall here, and over the years, the sun bleached the paint around it, leaving this rectangular section a slightly different color. The screws, nails, bolts, or whatever hardware held the shelf to the wall may have also cracked the paint as it got old, leaving a kind of border marking its presence.

There's also some handwriting on the surface; I assume they're measurements. Clearly, you wouldn't have scribbled on a finished wall, so the writing must have come much later, after someone decided to cover up this surface. (Possibly the same time that the drywall went in, if not the same person.) Just for fun, I tried measuring walls, doors, and bits of trim hoping to find something that measured 34 inches, 33¼ inches, or 53½ inches. No luck. So what were they measuring and where are those pieces now?