Rieber started from the University of California where he became interested in making an echo from underground strata to locate oil. He moved to Los Angeles, where his father was a professor of classical languages and a college dean. Frank invented a complex recording seismograph carried on a motor truck, wherewith he set off explosive bombs and registered echo earthquakes from every important underground layer. These layers identified oil-bearing strata, so that the marks on a revolving drum practically mapped a section underground for a guide to oil drilling. He moved to New York and established war inventions, among them phonograph disks for repeating whole conferences of many talkers. He founded Geovision Ltd., a company which greatly abbreviated the scanning of echoes for subterranean mapping. Then he died suddenly, like Hinkley, in the full flower of a brilliant mind. Rieber and I corresponded for years on invention gadgets, comparing notes by letters, and meeting all too rarely. To me he was one of our most productive physicists, always inspiring. He was convinced that discovery of petroleum will endlessly increase and will become automatic. He and I looked downward into the shell of the globe. This decade I devoted primarily to writing and publication, some of the writing voluminous and still unpublished. In 1941 I moved into an office in Hawaii Hall of the University of Hawaii in Honolulu. My paper work consisted primarily in completing, revising, and illustrating a memoir on “Origin and development of craters,” in cooperation with the Geological Society of America. The censor chosen by the Society was Dr. Howel Williams of the University of California, who cordially endorsed the book. The Society subscribed $350 from its Penrose Fund to assist with drafting and clerical work on the substantial results of our observations of Hawaiian craters in the twentieth century. The groundwork had long been laid, for beginning under Alexander Agassiz at the Museum of Comparative Zoology in Cambridge and during my visit to Vesuvius in 1906, I planned a book on volcanology. Later, in 1910 after careful study of the work of Dana, Hitchcock, and Brigham on Hawaiian volcanoes, I started analysis of Kilauea Volcano in the nineteenth century. Thus this one large volume with photogravures, maps, and diagrams covers the history of observations and conclusions from Hawaiian Volcano Observatory work for thirty years.