Vacuum History Fact
March 12, 1824
Birthday of Gustav Kirchhoff, German physicist who, with Robert Bunsen, established the theory of spectrum analysis. He found that when light passes through a gas, the gas absorbs those wavelengths that it would emit if heated, which explained the numerous dark lines (Fraunhofer lines) in the Sun's spectrum.
March 12, 1895
Birthday of Leo Esaki, Japanese physicist who shared (with Ivar Giaever and Brian Josephson) the Nobel Prize in Physics (1973) in recognition of his pioneering work on electron tunneling in solids. Esaki's discovery led to the creation of the Esaki diode
, with practical applications in high-speed circuits found in computers and communications networks.
March 14, 1939
John Dubrovin files U.S. patent No. 2337849 for a mechanical oil-sealed vacuum pump, sold as the now classic Welch Duo-Seal� pump.