Edward Bulwer-Lytton - The Coming Race (1871)

http://en.wikipedia.org/wiki/Vril

"The Coming Race (original title), also reprinted as Vril: The Power of the Coming Race, is a novel by Edward Bulwer-Lytton, first published in 1871. The novel is an early example of science fiction. However, many early readers believed that its account of a superior subterranean master race and the energy-form called Vril was accurate, to the extent that some theosophists accepted the book as truth. Furthermore, since 1960 there has been a conspiracy theory about a secret Vril-Society."

246 pg. eBook