Midwest house built in the early 1900s has a thing on the wall, what is this thing?
Answer: This is the century-old equivalent of your circuit breaker panel. The two sockets on top are for screw fuses and the thing on the bottom is a knife switch like you’d see in the Frankenstein movies. The knife switch is missing its handle which would be bolted to where the hole is in the throwing arm. This is a 2 pole fused disconnect and was likely used for some large appliance like an electric stove or heater or something.