Lord Rutherford (1871–1937): the Newton of the Atom and the Winner
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Essays DOI: 10.1002/anie.200803876 History of Science Lord Rutherford (1871–1937): The Newton of the Atom and the Winner of the Nobel Prize for Chemistry, 1908 John Meurig Thomas* atomic physics · history of science · radiochemistry · Rutherford, Ernest 1. Introduction three towering achievements associated was largely his “boys”—a term which he with his name—the theory of nuclear used affectionately to describe his stu- When Ernest Rutherford, later disintegration (with Frederick Soddy, dents and collaborators—who had de- known as Lord Rutherford of Nelson, 1902–1903), his model of the nuclear veloped radar and other devices of died unexpectedly in 1937, the New atom (1911), and the discovery of the strategic military significance. It was York Times stated: “…It is given to but artificial disintegration of the nucleus his assistants Chadwick and Cockcroft few men to achieve immortality, still less (1919)—the first two, while based on (later Nobel Prize winners each in their to achieve Olympian rank, during their experimental evidence, were theoretical own right) who built the UK Atomic own lifetime. Lord Rutherford achieved concepts. Even more ironic is that Energy Authority. both. In a generation that witnessed one Rutherford was awarded the Nobel of the greatest revolutions in the entire Prize in Chemistry (not Physics) in history of science he was universally 1908. When news of this award reached 2. The Trajectory of Rutherford’s acknowledged as the leading explorer of him he laughingly commented that he Life the vast infinitely complex universe with- had observed many rapid transforma- in the atom, a universe that he was first to tions among radioelements, but none as This section deals first with his place penetrate.” rapid as his transformation from a of birth, New Zealand, then his period And when Sir Mark Oliphant, a physicist into a chemist.[2] as a researcher at Cambridge (1895– fellow Antipodean and student, collea- Distinctions between physics and 1898), followed by his professorships at gue, and friend of Rutherford in Cam- chemistry are often arbitrarily drawn; McGill University, Montreal (1898– bridge, who, along with Paul Harteck, and it is futile pedantically to emphasize 1907) and Manchester (1907–1919), discovered tritium, wrote a foreword to them, especially where great scientists and his position as the Cavendish Pro- a definitive work[1] on Rutherford in like Faraday and Rutherford are con- fessor of Physics at Cambridge (1919– 1999 he described him as “the greatest cerned. In this regard the comments 1937). experimental scientist since Faraday”. made by Rutherford in August 1931, Oliphant also recalled that “Max Born, when the centenary of Faradays discov- whose own contributions to theoretical ery of electromagnetic induction was 2.1. New Zealand (1871–1895) physics were formidable, told me that celebrated, are worth repeating:[3] “The Rutherford was the greatest scientist he more we study the work of Faraday, with The New Zealand of the Ruther- had ever known, including even Ein- the perspective of time, the more we are fords youth was an agrarian society that stein.” impressed by his unrivalled genius as an had been settled by Europeans for only Historians of science the world over, experimenter and a natural philosopher. a few generations. Yet they brought to not to mention active scientists them- When we consider the magnitude and the Antipodes their English and Scottish selves, generally argue that Rutherford extent of his discoveries and their influ- values of hard work, thrift, and a respect was the most accomplished experimen- ence on the progress of science and of for education, and endeavored to create tal physicist since Faraday. Yet the case industry, there is no honour too large to the institutions that would reward their can be made (see Section 2.3) that of the pay to the memory of Michael Faraday— pioneering activities. Rutherford absor- one of the greatest scientific discoverers bed these qualities, and throughout his of all time.” life he exhibited the energy and re- Rutherford, like Faraday, took out sourcefulness of his father and the thirst [*] Prof. Sir J. M. Thomas no patents even though he possessed the for knowledge of his mother, a former Department of Materials Science skills and made discoveries, especially teacher.[2] A bright student, he won a University of Cambridge early in his career, that would have scholarship to Nelson College (situated Pembroke Street Cambridge, CB2 3QZ (UK) interested businessmen. Rutherford at the tip of the South Island). Another Fax : (+44)1223-334-567 himself did not see his discoveries as competitive scholarship allowed him in E-mail: [email protected] opening the era of atomic energy. But it 1890 to enter Canterbury College in 9392 2008 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Angew. Chem. Int. Ed. 2008, 47, 9392 – 9401 Angewandte Chemie Christchurch, where he expanded his horizons culturally and intellectually. After completing his BA degree in 1892 he proceeded to take his MA (in mathematics and mathematical phys- ics), and in 1894 he began his first independent research. But he had fur- ther cause to remain in Christchurch, for his heart was captivated by Mary New- ton, his landladys daughter. (He was to marry her in 1900). His research cen- tered on the magnetization of iron by high-frequency discharge, work which enabled him to devise a sensitive meth- od of detecting radio waves. He had recognized that an already magnetized needle would lose some of the strength, in an alternating magnetic field, making it a suitable detector for wireless signals and a device of potential commercial Figure 1. J. J. Thomson’s research group in the Cavendish Laboratory, Cambridge, 1898. Rutherford is fourth from the left in the middle row; to his right is C. T. R. Wilson, of cloud- applicability. He published two papers chamber fame, who won the Nobel Prize in Physics in 1927. Of him, P. M. S. Blackett, another on this topic in the Transactions of the Cavendish physicist to win the Nobel Prize (1948), said: “Of the great scientists of his age, he was [4] New Zealand Institute. perhaps the most gentle and serene, and the most indifferent to prestige and honours.” The Rutherford applied for an 1851 Ex- polymathic Paul Langevin (1872–1946) was also a member of the Cavendish Research group at hibition Scholarship in 1894; the rules that time (bottom row, third from the left, next to J. J. Thomson). had just been changed to allow candi- dates from the British Commonwealth to apply for such prestigious awards. In addition, Cambridge University had al- tion of different gases, and other rele- 2.3. Montreal (1898–1907) so just changed its statutes and now vant characteristics. permitted graduates from other univer- In 1896 radioactivity was discovered By the time Rutherford found his sities to pursue research there. Enrolling by Becquerel, and soon both Marie feet in McGill University, the omens in 1895, Rutherford was the first re- Curie, in Paris, and Rutherford, in Cam- were particularly good. First, the labo- search student under the new regula- bridge, pursued quantitative studies of ratories of the Department of Physics tions. He joined the Cavendish Labora- the phenomenon. The attention of the there were exceptionally well equipped: tory, whose Director was J. J. Thomson worlds scientific community, especially they were arguably the best in North (Figure 1).[5] after Pierre and Marie Curie (and Gus- America at the time. This was because tave Bmont) discovered polonium, was of the munificence of Sir William Mac- now riveted to radioactivity. For the Donald, a rich benefactor who had said 2.2. Cambridge (1895–1898) next four decades Rutherford and his that he wanted McGill to have the colleagues focused on radioactivity resources in physics comparable to Two months after Rutherfords ar- through its connections with atomic those of the Cavendish Laboratory in rival in Cambridge, X-rays were discov- physics, nuclear physics, and nuclear Cambridge. Not only was there the most ered (in November 1895) by Wilhelm chemistry. advanced equipment, even the stores Conrad Rntgen. And since this new In his work on uranium, using ab- had chemicals that hardly a department radiation exerted a marked effect upon sorption experiments (with rays imping- of physics or chemistry anywhere in the the discharge of electricity in gases (a ing on foils of various thicknesses) he world could rival, there being a good topic of great interest to Thomson),[6] observed that one type of radiation was supply of the then very costly radium Rutherford was quick to seize the op- readily stopped, another penetrated fur- bromide, for example. Second, the 21- portunity of collaborating with “J.J”. ther. He named the two types of radia- year-old Frederick Soddy, a former The collaboration yielded a classic pa- tion alpha and beta, because, he ex- student of Aberystwyth in Wales and per in 1896 on the theory of ionization.[7] claimed, he was a simple man and liked Merton College, Oxford, and a brilliant X-rays generate the positive and nega- simple experiments and explanations! experimentalist, had just been appoint- tive ions, which are attracted to electro- A physics professorship at McGill ed lecturer in chemistry at McGill. des, so that he could readily measure University in Montreal fell vacant in Rutherford and Soddy entered into a currents. Work of this kind continued for 1898. Thomsons advice was sought, and most rewarding eighteen-month collab- much of 1896 and 1897, with Rutherford he gave a glowing reference for Ruth- oration from October 1901 to April examining the ions velocities, their erford.[8] 1903, during which time they produced rates of recombination, the electrifica- nine major papers laying the founda- Angew. Chem.