Kamerlingh Onnes, Heike

Kamerlingh Onnes, Heike

(b. Groningen, Netherlands, 21 September 1853; d. Leiden, Netherlands, 21 February 1926)

physics.

Kamerlingh Onnes was the son of a well-known manufacturer in Groningen. After attending secondary school, he was admitted in 1870 to the University of Groningen, where he studied physics and mathematics. In November 1871 he passed the intermediate examination for the bachelor’s degree, whereupon he spent some time at Heidelberg. There he studied for three semesters with Bunsen and Kirshhoff, a tenure that was made possible by the Seminarpreis. Earlier he had won two other competition prizes, the gold medal of the University of Utrecht and the silver medal of the University of Groningen, both for research on the chemical bond. In April 1873 he returned to Groningen to complete his studies under R. A. Mees. In June 1876 he passed his doctoral examination, and on 10 July 1879 he defended his dissertation, entitled “Nieuwe bewijzen voor de aswenteling van de aarde” (“New Proofs for the Axial Rotation of the Earth”), a subject which, stimulated by Kirchhoff, he had started to study at Heidelberg. On the basis of this dissertation, in which he showed that he was also an excellent mathematician, he was awarded the doctorate magna cum laude.

In 1878 Kamerlingh Onnes was appointed assistant to Johannes Bosscha, who was then the director of the Polytechnic School (later the Technical University) at Delft. In 1880–1881 and 1881–1882 he lectured there for Snijders and Bosscha. During this time he was in close contact with van der Waals, who was then professor of physics in Amsterdam, and thus he became acquainted with problems related to the molecular theory of matter. An indication of this is found in his article “Théorie générale de l’état fluide” (1884).

In 1882 P. L. Rijke, professor of physics at Leiden, retired and kamerlingh Onnes was appointed his successor at the age of twenty-nine. He held this professorship, which included the directorship of the physics laboratory, for forty-two years.

The period in which Kamerlingh Onnes worked can be characterized as transitional for physics. The increasing importance of experimental physics is demonstrated by his appointment to the first chair of experimental physics in the Netherlands. Before then experimental and theoretical physics were not separated. On the other hand, the mechanistic image of physics was gradually being abandoned under the influence of Maxwell’s theory of electromagnetism; physicists were also gradually coming to believe that matter is not a continuum but has a corpuscular nature. When Kamerlingh Onnes came to Leiden most physicists still adhered to the idea of continuity, but Boltzmann and van der Waals in particular were promoting the corpuscular theory.

In his inaugural address at Leiden (11 November 1882), “The Significance of Quantitative Research in Physics,” Kamerlingh Onnes stated: “In my opinion it is necessary that in the experimental study of physics the striving for quantitative research, which means for the tracing of measure relations in the phenomena, must be in the foreground. I should like to write ‘Door meten tot weten’ [‘Through measuring to knowing’] as a motto above each physics laboratory.” This motto was a declaration of principle to which he always remained loyal.

In conducting his research and developing the necessary facilities Kamerlingh Onnes showed an enormous capacity for work, the more admirable because he was in very delicate health. His strong will and the great devotion and care of his wife, Elisabeth, enabled him to achieve what he did.

When Kamerlingh Onnes received his appointment at Leiden, he made it his purpose to give experimental support to van der Waals’s theory of the behavior of gases and especially to the “law of corresponding states.” This theory is based on the hypothesis that a gas consists of molecules circulating and exerting forces on each other. The law of corresponding states, which van der Waals had derived from his equation of state but which had a wider validity than for this form of the equation alone, says that all gases behave in exactly the same way and obey the same equation of state, when the units in which pressure, volume, and temperature are measured are adapted to the gas under specific consideration.

Kamerlingh Onnes was greatly interested in this theory, for he had concluded that the conformity in the behavior of gases could be found in “the stationary mechanical similarity of the substances,” as he stated in his Nobel address. He was “mightily attracted” by the idea of carrying out precise measurements in order to verify the results of this theory. For this purpose he would have to consider the behavior of gases with simple molecules having low condensation temperatures. Moreover, since it would be important to have a large range of temperatures at his disposal, it was desirable to use the lowest temperatures possible. Just five years earlier (December 1877) Cailletet and Pictet, using different, methods, had liquefied air for the first time and so opened this new temperature region. It was necessary for Kamerlingh Onnes first to build an apparatus for the liquefaction of air in large quantities. Here the advantage of his method became evident. He did his work with great accuracy and perseverance, systematically, and with attention to all details, thus obtaining important results and advancing far ahead of all other researchers in this field. In 1892 his apparatus for the “cascade method” (using liquid methyl chloride and ethylene) for the liquefaction of oxygen and air was ready . (Boiling points of oxygen and air of normal composition are –183°C. and –193°C., respectively.) In the meantime much information was obtained about the behavior of pure gases and binary gas mixtures, a study that could be extended, after 1892, to lower temperatures.

The research of Kamerlingh Onnes and his collaborators followed two lines, one related to van der Waals’s theories (equation of state, viscosity, capillarity), and the other to the theoretical work of Lorentz (magnetorotation of the plane of polarization, Kerr effect, Hall effect). In a volume commemorating Kamerlingh Onnes’ forty years as a professor Lorentz referred to an earlier book (1904), similarly in his honor:

Many a physicist would be glad if, at the end of his career, he could look back at researches of the quantity and importance of those which are described in that book. But in the following years all this proved to be only an overture to a higher flight in which results and points of view were reached of which originally even the most daring imagination had not been able to dream.

This “higher flight” became possible by the liquefaction of hydrogen and helium, which have boiling points of –252.7°C. and –268.9°C. (20.4 K. and 4.2 K.). In February 1906 the hydrogen liquefier was ready, and on 10 July 1908 helium was first liquefied. Construction of the helium liquefier was facilitated by knowledge of the law of corresponding states. With this liquefaction a vast new temperature region was opened for research—a field in which, until his retirement in 1923. Kamerlingh Onnes remained absolute monarch.

It was evident that the simple van der Waals law, ,where p, T, and V are pressure, temperature, and volume and R, a, and b are constants, could not represent the results of the measurements quantitatively. Therefore Kamerlingh Onnes set up the experimental law where A (= RT for one mole), B, C, . . ., which he called the virial coefficients, depand on the temperature. For this dependance he wrote with similar expressions for C, D, F, and F. In this way he had twenty-five coefficients to describe the measured values. This did not lead to a better formulation of the law of corresponding states, but the second virial coefficient B and sometimes C as well are commonly used to represent deviations from the ideal gas law.

The study of the resistance of metals was Kamerlingh Onnes’ second major field. Originally accepting the idea expressed in 1902 by Kelvin, he expected that with decreasing temperature the resistance, after reaching a minimum value, would become infinite as electrons condensed on the metal atoms. Later, when this proved to contradict experimental results, he supposed that the resistance, caused by Planck vibrators which lose their energy at low temperatures, would become zero. This proved to be true although, for certain metals, in a way different from that he expected. In order to diminish the influence of impurities, very pure mercury resistors were prepared. To Kamerlingh Onnes’ great surprise the resistance showed a discontinuous decrease to zero. Discovered in 1911, this phenomenon, which he called superconductivity (later superconductivity), was found for various metals having different temperatures. J. Bardeen, J. N. Cooper, and J. R. Schrieffer gave a theoretical explanation of this phenomenon in 1957.

Kamerlingh Onnes had originally hoped that this property would allow him to establish strong magnetic fields without cooling difficulties; but he soon found that the superconductive state disappears in a magnetic field of a temperature-dependent value, never very high in the cases he studied. Also, a current sent through a superconducting wire destroys the superconductive state by its own magnetic field. Only today, after the discovery of alloys that can support strong the possible to take advantage of superconductivity for cheap production of very intense magnetic fields.

In 1913 Kamerlingh Onnes received the Nobel Prize in physics “for researches on the properties of matter at low temperatures, which researches have among others also led to the liquefaction of helium.” He received honors from the Dutch and foreign governments and was a member of many academies and societies. An especial honor was his election to membership in the Royal Academy of Sciences in Amsterdam before he was thirty.

Kamerlingh Onnes was also concerned with the application of low temperatures in everyday matters such as food preservation, refrigerated transport, and the production of ice. In 1908, at the opening ceremonies of the first International Congress of Refrigeration in paris, he “formally proposed the creation of an international organization of refrigeration which would further the work of the congress.” He insisted that one of the commissions be devoted to scientific problems. In the Netherlands he stimulated the foundation of the Nederlandsche Vereeniging voor Koeltechniek, of which he was president until his death. Another organization for which Kamerlingh Onnes was responsible was the Vereening tot Bevordering van de Opleiding tot Instrumentmaker (1901). The workshops of his laboratory were organized as a school, the Leidsche Instrumentmakersschool. This establishment has been of great importance in training instrument makers, glassblowers, and glass polishers in the Netherlands.

BIBLIOGRAPHY

I. Original Works. Most of Kamerlingh Onnes’ writings can be found in the Proceedings of the Section of Sciences of the Royal Netherlands Academy of Sciences in Amsterdam and the Verhandelingen (later Verslagen ) of the meetings of the Academy. Reprints of these works are in Communications from the Physical Laboratory at the University of Leiden. Review articles on most of his research can also be found in the Reports and Communications presented by the president of the First Commission of the International Institute of Refrigeration to the third and fourth International Congresses of Refrigeration.

Among his works are “Algemeene theorie der vloeistoffen,” in Verhandelingen der K. akademie van wetenschappen, 21 (1881), and the following writings that appeared in Communications from the Physical Laboratory at the University of Leiden : “On the Cryogenic Laboratory at Leiden and on the Production of Very Low Temperatures.” in Communication, 14 (1894), which gives a review of the work of the first twelve years, including the liquefaction of oxygen; “The Importance of Accurate Measurements at Very Low Temperatures.” in Communication, supp. 9 (1904), his address as rector magnificus of the University of Leiden on its 329th anniversary; “Die Zustandsgleichung,” in in Communication, supp. 23 (1912), repr. from Encyklopädie der mathematischen Wissenschaften, V, pt. 10 (1912), written with W. H. Keesom; “Untersuchungen über die Eigenschaften der Körper bei niedrigen Temperaturen, welche Untersuchungen unter asderen auch zur Herstellung von flüssigem Helium geführt habn,” in Communication, supp. 35 (1913), his Nobel adress; and “On the Lowest Temperature Yet Obtained,” in Communication, 159 (1922), a paper read at the joint meeting of the Faraday Society and the British Cold Storage and Ice Association, repr. from Transactions of the Faraday Society, 18 (1922).

The liquefaction of hydrogen is described in Communication, 94 (1906), and that of helium in Communication, 108 (1908). The empirical eauation of state is introduced and discussed in Communication, 74 (1901). The superconductivity of mercury is treated in Communication, 122B and 124C (1911).

II. Secondary Literature. In Memoriam Heike Kamerlingh Onnes (Ledien, 1926) contains many of the newspaper obituaries and addresses at scientific societies, a review of his work, and a sketch of his personality; most of these are in Dutch. A similar work is Ernst Choen, “Kamerlingh Onnes Memorial Lecture,” in journal of the Chemical Society (1927), p. 1193. see also Gedenkboek aangeboden aan H. Kamerlingh Onnes 10 Juli 1904 (Leiden, 1904), and Het Natuurkundig laboratorium der Rijksuniversiteit te Leiden in de jaren 1904-1922 (Leiden, 1922).

J. Van Den Handel