Pics of surgistors make me think the device along the top edge in your last pic is that. Sounds like what we'd now call a PTC thermistor. Basically its high resistance when cold, and low resistance when hot. It slowly brings voltage up instead of the usual surge of current that happens when you throw the switch. Its nice for the switch and the transformer.
Looks like its fairly mechanical in nature. I see what looks like a bi-metal strip along the bottom and what I presume must be contact points at the left. Taking a guess at it, initially the current runs through the resistor until the heat causes the bi-metal strip to bend over and close the connection across it.
A modern part would be something like an Amphenol CL-80. They aren't mechanical but functionally serve a similar purpose.
Looks like its fairly mechanical in nature. I see what looks like a bi-metal strip along the bottom and what I presume must be contact points at the left. Taking a guess at it, initially the current runs through the resistor until the heat causes the bi-metal strip to bend over and close the connection across it.
A modern part would be something like an Amphenol CL-80. They aren't mechanical but functionally serve a similar purpose.