Edward Bullard

Sir Edward "Teddy" Crisp Bullard FRS^[1] (21 September 1907 – 3 April 1980) was a geophysicist who is considered, along with Maurice Ewing, to have founded the discipline of marine geophysics. He developed the theory of the geodynamo, pioneered the use of seismology to study the sea floor, measured geothermal heat flow through the ocean crust, and was one of the first to find new evidence for the theory of continental drift.^[2][3]

Early life

Bullard was born into a wealthy brewing family in Norwich, England. He was educated at Norwich School and later studied Natural Sciences at Clare College, Cambridge.^[1][4] He studied under Ernest Rutherford at the Cavendish Laboratory of University of Cambridge and in the 1930s he received his PhD degree as a nuclear physicist.

As it was the Great Depression and he was married he had to find a career to survive on. In the 1930s nuclear physics did not seem to be it so he switched to geophysics. During World War II he was an experimental officer at HMS Vernon, and worked on the development of degaussing techniques to protect shipping from magnetic mines.

Career

Bullard held a chair at the University of Toronto from 1948–50 and was head of the National Physical Laboratory between 1950 and 1955. He returned to Cambridge in 1955, first as an assistant in research, then as a Reader and finally to a chair created for him in 1964. He was a founding fellow of Churchill College, Cambridge

Bullard became one of the most important geophysicists of his day. He also did studies of the ocean floor even though he suffered from seasickness and could rarely take scientific trips on the ocean. He was important to dynamo theory, hence his most important work concerned the source of the Earth's magnetic field. He was often frustrated by efforts to increase geophysical interest at the University of Cambridge. In his career he won the Hughes Medal, the Vetlesen Prize and the Gold Medal of the Royal Astronomical Society.In 1965, he was awarded the Alexander Agassiz Medal from the National Academy of Sciences for his significant investigations of the earth from its surface to its core.

Then during the early 1960s Bullard and his associates used a computer to try to fit all of the continents together. Instead of using the shorelines, like other geophysicists had done, he used a depth of 914 meters (3000 ft) below sea level. This depth corresponds to about halfway between the shoreline and the ocean basins and represents the true edge of the continents. By doing this he discovered a near perfect fit among the continents put together. With this discovery he helped further the idea of a supercontinent that earlier geophysicist, Alfred Wegener, had suggested calling Pangaea.

After retiring from Cambridge he settled to a position at the University of California, San Diego. Bullard died in La Jolla, California 1980. His papers are held by the Churchill Archives Centre.

See also

• List of geophysicists

References

External links

• University of California San Diego obit at the Wayback Machine (archived July 13, 2007)
• Bullard photo
• Cambridge article
• Edward Bullard at the Mathematics Genealogy Project