Nequa, or, The Problem of the Ages,
by Jack Adams (1900)

Reginald's Science Fiction & Fantasy Literature 1700–1974, states that Nequa was one of the first "Feminist science fiction novels." Reginald reveals that the author on the title page, Jack Adams, was a pseudonym for Grigsby, but the back page of the copy I own lists Dr. T. A. H. Lowe as the writer.

Whoever wrote it, the book describes a trip to a world inside the earth where both sexes are equal, after women have put an end to war and demanded freedom from the domination of laws made only by men.

There are airships that ride storms, a Library of Universal Knowledge with electric keyboard to order instantly delivered books, electric "carriages," and tables laden with food that appear out of the floor. There are pages of explanation on the demise of the old political way of competition and the growth of the new way of "Motherly love," and on the last two pages, Jack Adams, while "dressed in the costume which is peculiar to women in the outer world," reveals that he is a she whose name on the surface of the earth is Cassie Van Ness.

He/she reveals this secret to her lover as he leaves the center of the earth without her. Has anyone ever found volume two?

—Mark Esping