Before the narrative which follows was placed in my hands, I had never seen Dr. Walter T. Goodwin, its author. When the manuscript revealing his adventures among the pre-historic ruins of the Nan-Matal in the Carolines (The Moon Pool) had been given me by the International Association of Science for editing and revision to meet the requirements of a popular presentation, Dr. Goodwin had left America. He had explained that he was still too shaken, too depressed, to be able to recall experiences that must inevitably carry with them freshened memories of those whom he loved so well and from whom, he felt, he was separated in all probability forever.