Over the years have seen some very creative wiring in houses!! To save wire only run a hot wire to a bathroom for lights then hook to a metal water pipe for a neutral to make it work. Older houses with a fuse box with both hot an neutral with a fuse. So when you measure from the hot or (neutral) to ground you get 60 volts AC. The house I grew up in was wired like this. Have a Army generator from 1952? model PE75 that has the 60 volts to ground on both pins. The design dates from 1936 and was used until the mid 70s. the outlet was 2 pin twist lock. ?