The Sunless City: A Classic Sci-Fi Novel

This novel was originally published in 1905 and describes Professor Josiah Flonatin's discovery of an underground (or, better to say, underwater) city, situated on the bottom of a "bottomless" lake somewhere in the Rocky Mountains. Everything in the city is different from what Flonatin is used to. The local currency is tin, the streets are paved with gold, and the city is ruled by women...