1880-1966

English physicist who independently discovered the powder method for x-ray analysis of crystals. After receiving his Ph.D. at Yale in 1909, Hull joined General Electric as a research physicist in 1914, and later served as assistant director of its research laboratory. In 1916 scientists Peter Debye and Paul Scherrer devised the powder method technique of x-ray analysis. Unaware of their work, a year later Hull used this same method to examine the crystal structure of several common metals, including iron. He then turned his attention to electronics, inventing several components used in electric circuits, including the magnetron, an oscillator that generates microwaves.