Here they never soldered as far as I know but rather used screws and special nuts. Those nuts had 3 "wings" that crook towards the screw head like fingers of a half-closed fist. All wires were wrapped around the screw, the nut screwed on and tightened, then the entire splice was wrapped with cloth tape. I've seen that method used in wiring from the early 1900s/late 1800s through early 1960s. I've got to look around, I'm pretty sure I cut some of those out and kept them.
