Review by Darius M. Klein: "A Classic of the Genre" is how Jessica Salmonsen has described this work. Robert Ames Bennet was primarily a writer of Westerns, but also wrote two Lost Race romances, one of which is "Thyra: A Romance of the Polar Pit". The plot concerns a group of explorers who fly in a balloon to the North Pole, where they discover, via an opening, that the earth is indeed hollow. Once inside the earth they encounter Viking and Neanderthal communities, along with survivals of Mesozoic megafauna. "Thyra" manages to intertwine the Utopian Lost Race and Lost World subgenres into a single, action-packed plot which never meanders or digresses. The first Viking community upon which the heroes stumble after they enter the bowels of the Earth (and where they find the eponymous heroine) is an unlikely Christian-Socialist Utopia. As they penetrate further into the Earth's interior, they encounter those Vikings who have given themselves over to idolatry and human sacrifice, along with a community of stereotypically aggressive and bestial Neanderthals. At the novel's climax, they have a perilous close encounter with some demonic prehistoric reptiles in the Hela Pool (a particularly well-written scene). The copy of this work which I obtained is a photocopy of the microfilm of the original 1901 edition, which has delightfully quaint illustrations; I don't know if they have been reproduced in the "Lost Race and Adult Fantasy Fiction" series' edition. Mr. Bennet's other Lost Race Romance, "The Bowl of Baal", also combines Lost Race and Lost World motifs, and is recommended here. Of the two, however, "Thyra" is the better.