antique white ironstone industrial electric light bulb sockets w/ turn key paddle switches

Unmarked Hubbell electric light bulb sockets with the good old tab style switches, early 1900s vintage. We did not test these, but they look clean and complete and we see no reason why these wouldn't work. They're marked 250W 250V.

They do have discoloration and / or staining to the china - I haven't tried to clean that, bleach these or anything besides a quick wipe with a damp cloth. One has a chip.