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Arthur Day (image source: xxx)
Biographical Information
Born in 1869
Died in 1960
Dr. Arthur Day has a list of accolades and degrees that would impress anyone in or out of the field of Geophysics. Below is a link to specific information with respect to Dr. Day's education and degrees, as well as positions held in the scientific community. His associations with the scientific community as well as his contributions to the world of geophysics, and especially Plate Tectonics, are legendary.
He received his Ph.D. from Yale University in 1894, followed by further degrees (Sc.D.) from Columbia, Princeton, and University of Pennsylvania. (love that Ivy League!!!) Dr. Day is well represented in the societies he worked with throughout his distinguished career. He served as the Secretary and Vice President of the National Academy of Sciences, Vice President and President of the Geological Society of America, and President of the Philosophical Society of Washington, to name but a few.
Specific contributions to plate tectonic theory / solid Earth geophysics
Dr. Day's career spans decades, but arguably his greatest tenure was as the director of the Geophysics Laboratory, through Carnegie Institute. He held this position from 1907 until 1936. His research experience was extensive in physics, physical chemistry, volcanology, and seismology. Much of his early work in understanding the geophysical nature of the Earth's interior came from his famous drilling projects in and around Yellowstone National Park. His greatest passion was seismology and volcanoes. After his retirement, he traveled to New Zealand to continue his life's work, where he was forced to give up field work due to a physical breakdown.
Other interesting scientific contributions
Outside of the arena of Plate Tectonics, Day was a major contributor to the war effort during World War 1 by coupling with Bausch and Lomb to provide high quality optical glass for gun sites, rangefinders, and periscopes. If you Google "The Optical Glass Rivalry" you should find more about his involvement and contributions.
Other cool stuff you should know
The Geological Society of America established one of it's highest honors in Dr. Day's name, The Arthur L. Day Award, given to scientists who demonstrate excellence both in and out of the laboratory. One of Dr. Days strengths was getting foundations to fund the different projects he and his colleagues were passionate about during the early part of the twentieth century. Pioneering work in seismology is largely due to the individual efforts of this scientist. See "Shaking Things Up" for further information on these early investigations.
Bibliography:
Abelson, P. H.., Arthur Lewis Day, National Academy of Sciences Biographical Memoirs, 27 - 47. 1975
Sullivan, Eugene C., Arthur Louis Day, American Ceramic Society Bulletin, 20 (No. 7), 252 - 254, 1941