Gustav F. Ebding

Gustav F. Ebding (February 9, 1887 - August 14, 1975) was an American machinist and inventor, advocate of a concave-type Hollow Earth theory (comparable to that proposed by Cyrus Teed, a.k.a. Koresh), and sometime political activist, having legally challenged Hoover's 1928 election as illegitimate (and subsequently faced an insanity charge for his trouble) and mounted a failed run for Congress in 1930.