they appear to be from around that time.

They could well be from that time period, but they are still around today. We used to call them "door" fuses.

Can you guess why we consider them a REAL PITA???

Regular shotgun stick won't work. Fusing stick has nothing to grab. You've gotta climb/bucket up, remove it and replace it hoping it ain't faulted, or find a large closing fork and try it very sloppy.

I HATE when these things happen!!!

Yeah! The newer ones are made of fiberglass I was told by a trouble person from Hydro.. He also told me they are more prone to arcing and burning up than the older porcelain ones. ):
A.D

Many of them have gone into flames on the poles around here. Most have been replaced, but there are still the replacement doors hanging on the crossarms.

Ian A.

Wow. I've heard linemen refer to primary cutouts as "doors", which never made sense to me. Now it does. Kinda like "cord cap", and "solid neutral", terms that recall a time when there were both solid and fused neutrals, etc.

So what is the origin of the "cord cap" term?