What the heck is this?

[TonewolfAmps]

Someone brought in an old 1940s Dickerson guitar / lap steel amp to get working and this component was in it. It ran from the high input jack tip to the grid of the first preamp tube (6sf5). I tested it with my meter it has no continuity or resistance (well up to 20M anyway lol). There were no other resistors or capacitors in parallel with it from the input to the first tube grid. I replaced it with a normal grid stopper resistor and fixed some other things and the amp works great but I wanna know what this was.

[sluckey]

It's a bias cell (bias battery).

[teemuk]

It's a "bias cell". Basically a battery.