What Are You Looking Through AT?

I’ve been working on windows lately. (and really what old house owner ISN'T always working on windows?) I repaired and re-varnished all the upstairs windows last summer, but had never gotten to putting stops back into the window frames after I did all that, because I didn’t want to have to cut all the stop material.

As part of the salvage that FHP did a couple weeks ago I was able to get some stop material from the windows in the old Law School. But this is not ordinary stop, it was all screwed into place (which is WAY more convenient if you ever have to take the windows out. What I noticed right away was that the stop was mitered at the corners. All stop I’ve ever stopped (pun intended) to look at was butt jointed.

When I started to remove the stop I discovered that the front was mitered and the back was butt jointed! Here is a shot of a side piece:


Here is a shot of the top piece:


And together:


And tight:


And from the back:


The windows I took the stop from were all much bigger than our windows, so I’ve had to cut them down. A few also had extra nail holes so I’ve actually replicated all the cuts with my hand miter box. I think this is a very ingenious way to fit the parts together. Has anyone else ever seen this?