Albert Francis Birch August 22 , 1903 - January 30 , 1992 A Biographical Memoir

Francis Birch was a founder of the science of solid earth geophysics. He demonstrated how study of the physics of minerals and rocks could lead, in conjunction with knowledge of seismic structure and geochemical abundances, to an understanding of the constitution of the Earth. Birch obtained, in his Harvard University laboratory, some of the first reliable data for the elasticity (especially at high pressures and temperatures), thermal expansion and thermal conductivity of rocks and minerals. Based on his own and other experimental results and his analytical perception, he pioneered our understanding of the composition, structure, and temperature in the Earth’s interior and developed models of the Earth’s initial differentiation. Francis Birch was fascinated by the Earth and worked his whole life refining his analysis of it. At Los Alamos National Laboratory, during World War II, Birch played a crucial role in translating his considerable Harvard experience in the high pressure and temperature mechanics of materials to developing a gun-type device that evolved into the first of the two atomic bombs produced by the Manhattan Project. Although the decision for their deployment is still controversial, it is clear that these explosions decisively ended World War II in August 1945. Francis Birch returned to Harvard and remained continuously on the faculty until his death in January 1992. Birch had a remarkable and extremely productive scientific career that spanned some sixty years.