An omnibus edition of Undersea Quest, Undersea Fleet and Undersea City.
When Jim Eden's uncle, the inventor of a valuable undersea device, disappears while testing a new undersea mining process, Eden heads for the undersea mining colony to investigate on his own.
Jack Williamson (John Stewart Williamson, 1908–2006) was an American science fiction author.
Jack Williamson has been in the forefront of science fiction since his first published story in 1928. Williamson is the acclaimed author of The Humanoids and The Legion of Time. He is considered to be "The Dean of Science Fiction".
Jack Williamson. Wikipedia.