The Digging Leviathan by James P. Blaylock

His steampunk novel Homunculus won the Philip K. Blaylock, one of the pioneers of the steampunk genre, has written eighteen novels as well as scores of short stories, essays, and articles. World Fantasy Award winning author James P. Blaylock's Zeuglodon is the most fun I've had reading in ages, with an unabashed budding cryptozoologist protagonist, mummified mermaid, underground passages, lost world, and the scariest busybody since Margaret Hamilton put Toto in her bicycle basket. Zeuglodon, set in the world envisioned in James Blaylock’s The Digging Leviathan, is a landscape of color, mystery, and adventure, in which reality and fantasy are shifting currents, and nothing is quite what it seems to be. But to awaken him might mean the end of his dream, the closing of the Windermere Passage, and the three intrepid explorers marooned in a savage land forgotten by time itself….

George, must descend into the depths of the hollow earth in order to return the Sleeper to his ancestral home on the shores of Lake Windermere. Pursued by kidnappers thinking of riches and murder, Katherine Perkins and her two cousins, junior members of The Guild of St. A skeletal hand clutching an iron key lies hidden within a mermaid’s wooden sarcophagus a hand-drawn map is stolen from beneath the floorboards an old museum an eccentric sleeping inventor dreams of a passage to the center of the hollow earth, and by dreaming of the passage, brings it into being….

The Digging Leviathan by James P. Blaylock