Johannes Diderik van der Waals higher temperatures. Nitrogen, oxygen, hydrogen, and helium subsequently succumbed to liquefaction. Heike Kamerlingh Onnes was significantly influenced by the pioneer work of van der Waals. In 1908, Onnes became the first to make liquid helium; this led directly to his 1911 discovery of superconductivity. Van der Waals started his career as a school teacher. He became the first physics professor of the University of Amsterdam when in 1877 the old Athenaeum was upgraded to Municipal University. Van der Waals won the 1910 Nobel Prize in physics for his work on the equation of state for gases and liquids. Johannes Diderik
Helium by Dutch physicist Heike Kamerlingh Onnes by cooling the gas to less than one kelvin. He tried to solidify it by further reducing the temperature but failed because helium does not solidify at atmospheric pressure. Onnes' student Willem Hendrik Keesom was eventually able to solidify 1 cm of helium in 1926 by applying additional external pressure. In 1913, Niels Bohr published his "trilogy" on atomic structure that included a reconsideration of the Pickering–Fowler series as central evidence in support of his model of the atom. This series is named for Edward Charles Pickering, who in 1896 published observations of previously