Röntgen rays, uranium rays and radioactivity

Nature was founded in 1869 under the editorship of the astronomer J. Norman Lockyer. Lockyer had initially envisioned his new weekly as a way to inform the educated British public of the latest achievements in British science, with the ideal end result of more financial support for science in Great Britain. However, largely due to the interests of Lockyer's scientific contributors, Nature quickly shifted away from its lay audience and became a specialist periodical aimed at scientific researchers.Footnote ⁷ By 1895, Nature was one of Britain's most influential scientific publications, a forum where British men of science could debate the important scientific questions of the day before an audience of fellow researchers.

Two important developments in the physical sciences give us the opportunity to examine Nature's place in the world of British scientific publishing at the end of the nineteenth century: the German physicist Wilhelm Conrad Röntgen's November 1895 discovery of X-rays (or, as they were often called before 1900, ‘Röntgen rays’) and the French physicist Henri Becquerel's March 1896 discovery of ‘uranium rays’, which Marie Curie renamed ‘radioactivity’ in 1898 after discovering that the phenomenon was not confined to uranium.Footnote ⁸ Röntgen's discovery was a scientific and popular sensation. It made the news in many English-language newspapers and journals and Nature was no exception. The ‘Notes’ column of 16 January 1896 mentioned Röntgen's findings, announcing that Röntgen had used his new waves to obtain pictures ‘showing only the bones of living persons’ and predicting that the ‘scientific world will look forward with interest to the publication of the details of Prof. Röntgen's work’.Footnote ⁹Nature's very next issue, published on 23 January, prominently featured the new discovery: the issue contained two letters to the editor and two longer articles on Röntgen rays. The physicist Arthur Schuster wrote to the editor to urge his fellow physicists not to discard the idea that Röntgen rays might be an unusual manifestation of light waves, a conclusion Röntgen's paper had rejected. J.T. Bottomley's letter noted that Röntgen's paper had concluded with the speculation that his rays might be longitudinal vibrations in the luminiferous ether and called attention to a passage in Lord Kelvin's Baltimore Lectures that seemed to anticipate the discovery of such a wave. Most famously, this issue of Nature printed the first translation of Röntgen's paper into English, written by the Manchester physicist Arthur Stanton.Footnote ¹⁰ The electrical engineer A.A.C. Swinton supplemented Stanton's translation with an article in which he reported, ‘I have, with the assistance of Mr J.C.M. Stanton, repeated many of Prof. Röntgen's experiments with entire success’. Swinton's article also included the first X-ray photograph taken in England.Footnote ¹¹

These letters and articles were the first in a rapid flood of pieces on the new phenomenon. In 1896, there were 139 articles in Nature about Röntgen rays, an average of nearly three per week. Two other British scientific weeklies, Chemical News and The Electrician, provide useful points of comparison: in 1896, Chemical News mentioned Röntgen rays twenty-eight times (an average of once every other week), The Electrician eighty-six (an average of 1.65 mentions per week).

Nature thus stands out for its sheer amount of material on Röntgen rays, but the comparison between Nature and its fellow weeklies shows that Nature's treatment of Röntgen rays was not necessarily unique. The formats of the pieces in Nature were wide-ranging; they included abstracts from other journals (usually foreign ones), reports of lectures about the rays, theoretical speculations like Bottomley's letter, summary articles written by Nature's staff, and original reports of experimental results like Swinton's. Chemical News and The Electrician both published material on Röntgen rays extremely similar to Nature's. Chemical News's coverage largely comprised reprints of articles published elsewhere or summaries of foreign research, but a handful of researchers did send preliminary experimental results to Chemical News or submit letters about the rays to Chemical News's occasional correspondence columns.Footnote ¹² Similarly, The Electrician included a large number of abstracts of foreign articles on Röntgen rays (most frequently from the Comptes rendus), as well as summary articles about the current state of Röntgen ray research and reports on lectures given about the rays. The Electrician also published correspondence discussing the nature of the rays,Footnote ¹³ and a few original research articles about Röntgen ray experiments.Footnote ¹⁴Nature was therefore the most popular weekly venue for pieces about Röntgen rays, but the types of article were not necessarily unique among British scientific weeklies aimed at an audience of researchers.

Monthly or quarterly research publications in 1896 contained far fewer articles about Röntgen rays than did the weeklies. The Philosophical Magazine contained eight articles about Röntgen rays that year; the Proceedings of the Royal Society of London ran twelve articles on the rays in 1896–1897; the Philosophical Transactions of the Royal Society did not run any articles on Röntgen rays until 1897. These numbers reflect the differences in format and submission process between the weeklies and other research periodicals. Unlike the weeklies, which ran brief submissions, the Philosophical Magazine, the Proceedings and the Philosophical Transactions ran lengthy articles detailing experimental methods and extensive data. Furthermore, monthly and quarterly research publications had a much longer delay between submission and publication than did the weeklies, especially publications such as the Philosophical Transactions, which were affiliated with a scientific society and whose articles were more extensively refereed before publication.

The data from both the weekly and the monthly or quarterly publications underscores two important points: first, that in 1896 Nature was not the only British scientific weekly where a researcher could or would submit interesting new research results; second, that scientific weeklies played a unique role in researchers' publishing strategies at the end of the nineteenth century because they offered researchers a forum where short articles could be printed quickly. The closest monthly competitor for these pieces was the Philosophical Magazine, whose ‘Intelligence and miscellaneous articles’ section contained pieces similar in length and content to the articles in weeklies. But the Phil Mag's monthly publication schedule usually meant a longer wait time between submission and publication than the wait for the weeklies. A few researchers sent the Philosophical Magazine pieces on Röntgen rays for ‘Intelligence and miscellaneous articles’ in 1896, for example, but none of these pieces appeared before April.Footnote ¹⁵ This suggests that specialist weeklies were able to capitalize on the intense interest in Röntgen's discovery by giving researchers the opportunity to present preliminary observations and theories about the nature of the rays to an audience of scientific specialists within a week of submission.Footnote ¹⁶

But, we might wonder, why would these researchers want to publish short pieces quickly at all? As Alex Csiszar's recent work has shown, by the end of the nineteenth century establishing priority for scientific discoveries was dependent upon being the first to publish an idea or experimental findings. Being the first to publish had been a way of establishing priority well before the nineteenth century, of course, but it was one method among many. By the late nineteenth century, however, being the first to lecture, teach or write a private letter about a discovery was no longer considered compelling evidence of scientific priority. The claim had to be made in print. The published item need not be long; there simply had to be something in print indicating that a particular man of science had presented his ideas to the public before his colleagues had done so.Footnote ¹⁷ Weekly periodicals were therefore well suited to establishing priority claims in the midst of a research boom.

When compared with the enthusiasm and the avalanche of research that followed the discovery of Röntgen rays, British weeklies' response to Becquerel's uranium rays was quite mild. Nature's ‘Notes’ and ‘Societies and academies’ columns mentioned Becquerel's discovery a handful of times in 1896, and J.J. Thomson devoted an article to a discussion of Becquerel's experiment and how it might cast light on the nature of Röntgen rays, but relatively few contributors seemed interested in uranium rays.Footnote ¹⁸ Similarly, The Electrician mentioned Becquerel's discovery only once in 1896, in a short note about recent experiments related to Röntgen rays.Footnote ¹⁹Chemical News was more enthusiastic, reprinting the full version of Becquerel's original paper on ‘uranium rays’ and also abstracting his subsequent articles on the rays.Footnote ²⁰ It might be tempting to accuse British publications of ignoring Becquerel (with the exception of Chemical News), but in fact the limited coverage of ‘Becquerel rays’ was typical of the physics community at the time. As Lawrence Badash has pointed out, physicists were in the midst of ‘an heroic age of radiations’, and at first Becquerel's rays did not stand out among the pack; they appeared to be an odd phenomenon confined to uranium salts, with no useful application.Footnote ²¹ In 1896, the Académie des sciences heard approximately a hundred papers about Röntgen rays but only three about Becquerel rays.Footnote ²² Becquerel himself followed his discovery of Becquerel rays with eleven months of unrelated research on optics. Not until the Curies discovered that materials besides uranium salts were capable of emitting Becquerel rays, in 1898, did most physicists begin to think of these rays as a phenomenon worthy of intense investigation.

Interestingly, although the Curies' discovery was widely regarded as groundbreaking and it quickly sparked the imagination of the British and American popular press, specialist periodicals in Britain contained only limited coverage of the Curies' work or their 1898 discovery.Footnote ²³The Electrician, which had so thoroughly summarized the Comptes rendus articles on Röntgen rays, contained almost no material on the Curies' radioactivity work before 1903 (the year the Curies won the Nobel Prize). Nature's coverage of the Curies' pre-1903 work on radium and polonium was confined to brief mentions in the ‘Societies and academies’ column. The Philosophical Magazine ran only one article from the Curies, a summary of a recent paper in the Comptes rendus de l'Académie des sciences, in February 1900.Footnote ²⁴ As with Becquerel, Chemical News led the British coverage of the Curies' radioactivity work, reprinting both a shortened English version of the Curies' November 1899 Comptes rendus paper on radioactivity and a full translation of Marie Curie's doctoral thesis in 1903.Footnote ²⁵

Why was the coverage of radioactivity in British publications so limited compared to the coverage of Röntgen rays? Significantly, in contrast to the material on Röntgen rays, few researchers in England contributed their own radioactivity work to British weeklies or society journals before 1903.Footnote ²⁶ In March 1902, the staff of The Electrician even remarked on the limited British coverage of Becquerel rays and the Curies' research in their leading ‘Notes’ column, writing,

These patterns of publication in radioactivity suggest something important about journals in the late nineteenth and early twentieth centuries. Several historians of science have argued that the twenty years preceding the outbreak of the First World War were an era of increasing international ties between scientific workers. The number of international scientific congresses increased dramatically between 1870 and 1914, fuelled in part by a desire to standardize terminology and units, and in part by the enormous boom in railway networks across Europe.Footnote ²⁸ With scientific internationalism on the rise, we might expect that scientific journals would take on a more international character, but this did not happen. Instead, many of the most influential scientific journals in Europe remained focused on serving a particular national scientific community. One good example is the Annalen der Physik und Chemie, Germany's most important journal of the physical sciences.Footnote ²⁹ Throughout the nineteenth century, the Annalen regularly published translations of important papers by foreign physicists, but German and Austrian researchers were responsible for the vast majority of the content of the Annalen. A similar case is that of Le radium, a Parisian publication founded in 1904 and devoted to radioactivity research.Footnote ³⁰ Like the Annalen, Le radium regularly published pieces by foreign scientists, but most of these articles by foreign scientists were translated by Le radium's editorial staff for the benefit of the French scientific community, and the majority of Le radium's original articles were written by French scientists.Footnote ³¹ Similarly, as we shall see later in the paper, Nature was explicitly dedicated to the British scientific community and the vast majority of its contributors were British. British periodicals such as Nature lacked a supply of articles on radioactivity primarily because there was not yet a strong community of radioactivity researchers in Britain.

Keeping in the race: scientific priority and Ernest Rutherford's career strategies

Nature's engagement with the new science of radioactivity would change dramatically with the rising career of the New Zealand-born physicist Ernest Rutherford, who by 1905 would arguably overtake the Curies as the world's most important radioactivity researcher.Footnote ³² In 1894, after earning his BSc from New Zealand's Canterbury University College, Rutherford applied for and won an 1851 Exhibition Scholarship from the British Crown in the first year the competition was open to students born in the colonies.Footnote ³³ He chose to continue his work in physics at the Cavendish Laboratory in Cambridge under the supervision of J.J. Thomson.

The young New Zealander worked at Cambridge until 1898, when he was hired as a professor of physics at McGill University in Montreal. Rutherford, who was only twenty-seven years old, had not expected to be named to the McGill position, despite Thomson's enthusiastic recommendation.Footnote ³⁴ McGill was a highly desirable appointment for a research physicist. The university was well funded and its Macdonald Physics Laboratory was one of the best-equipped research laboratories in the world; when it opened in 1893, the Macdonald building received international attention for its architecture, its enviable library, its expensive collection of experimental equipment, and the generous endowment of $150,000 designed to pay for the building's maintenance.Footnote ³⁵ Rutherford's ten years at McGill would be extremely fruitful for the burgeoning science of radioactivity. In 1903, Rutherford and his colleague, the chemist Frederick Soddy (1877–1956), demonstrated that radioactivity was the result of atomic disintegration and that radioactive atoms released matter as alpha, beta and gamma rays and changed their elemental identity. In 1907–1908, Rutherford and his colleagues in Montreal (minus Soddy, who had returned to England in 1903) undertook a spectroscopic study of alpha rays and were able to show that alpha rays were composed of helium particles.Footnote ³⁶

The major disadvantage of Rutherford's job at McGill was its location. As we shall see from Rutherford's correspondence, despite the presence of colleagues such as Soddy, the young physicist felt intellectually isolated in Montreal. The Macdonald Physics Laboratory, however well equipped with instruments, could not replace the sense of intellectual community Rutherford had experienced at the Cavendish. But intellectual isolation was not the only perceived consequence of Rutherford's remote ‘colonial’ appointment. In November 1899, Rutherford sent a paper to the Philosophical Magazine titled ‘Radioactivity produced in substances by the action of thorium compounds’. Rutherford believed that his results, which suggested that radioactive thorium could induce radioactivity in other substances, were some of his most interesting and important findings to date. But just two weeks after he submitted his paper, he discovered something most unwelcome: his chief competitors in the field of radioactivity research, Pierre and Marie Curie, had just published a new article in the Comptes rendus in which they argued that radium and polonium could induce ‘excited radioactivity’ in other substances.Footnote ³⁷ By the time Rutherford's paper appeared in the February issue of the Philosophical Magazine, his findings were no longer as groundbreaking as he had initially believed. His paper ended in a morose footnote acknowledging that the Curies had been the first to publish about the phenomenon of excited radioactivity.Footnote ³⁸

Being scooped by his French rivals was a blow to the ambitious Rutherford, who was extremely concerned about establishing priority for his work. A letter Rutherford wrote to his mother in 1900 reveals his competitive spirit, as well as his desire to publish his work quickly:

Rutherford's biographer, David Wilson, writes that losing the race to be first on excited radioactivity taught Rutherford ‘the hard lesson of the sheer distance of Canada from the centres of scientific activity in Europe where researchers could get their results printed, and claim priority of discovery, within a few days of submitting their work’.Footnote ⁴⁰

But Rutherford's misfortune was Nature's gain. Prior to the 1899 excited radioactivity scoop, Rutherford had not contributed to Macmillan's weekly; that would soon change. There were three major publications where Rutherford sent his work: the Proceedings of the Royal Society of London, the Philosophical Magazine and Nature. Rutherford was also on the board of two foreign journals, Le radium and Jahrbuch der Radioaktivität und Elektronik, but Rutherford preferred to direct his own papers to English-language journals. Both the Proceedings and the Philosophical Magazine had significant lag times between submission and publication (the Proceedings averaged six months, the Phil Mag three), which made Nature and its weekly publication schedule ‘exceedingly valuable’ to the priority-conscious Rutherford.Footnote ⁴¹ The ‘Letters to the editor’ column was particularly useful for this purpose: while longer articles in Nature might take up to a month to make it into print, the magazine still published many of its letters to the editor the same week they were submitted. Rutherford contributed over a dozen letters to the editor between 1901 and 1908 (when he began a job at the University of Manchester).Footnote ⁴²

Interestingly, Rutherford's desire to publish quickly did not lead him to seek out other weeklies besides Nature. Although Chemical News regularly covered Rutherford's papers and presentations, and although he and Soddy published a multi-part article on thorium emanations in Chemical News in 1902, after Soddy left McGill Rutherford ceased to contribute articles to Chemical News.Footnote ⁴³ Similarly, although Rutherford would later recall that he had admired The Electrician's material on theoretical physics (in particular Oliver Heaviside's contributions), and although Thomson had sent an abstract of one of Rutherford's forthcoming articles to The Electrician while Rutherford was at Cambridge, after leaving for McGill Rutherford did not send his experimental findings to that publication either.Footnote ⁴⁴ Why Nature and not Chemical News or The Electrician – especially given that Chemical News had been far more interested in radioactivity than had Nature? It was partly a question of discipline. Chemical News catered to Britain's chemists. Soddy identified as a chemist, but Rutherford viewed himself as a physicist (and was, indeed, rather bemused when he won the Nobel Prize in Chemistry), which explains why Rutherford co-authored with Soddy but did not single-author pieces for Chemical News. Similarly, The Electrician aimed itself at an audience of engineers and industrial scientists, and Rutherford considered himself neither.

Rutherford's choice of Nature over other weeklies was likely also about the relative prestige of these publications. As early as the 1870s and 1880s, scientific researchers in Great Britain were choosing Nature over other weeklies because it reached a readership that was positioned to evaluate scientific knowledge claims. Publishing in Nature legitimized one's work or views on a debate as properly scientific.Footnote ⁴⁵ An 1895 letter from William Crookes, editor of Chemical News, illustrates that Nature's readers were considered more scientifically qualified than the readers of other scientific weeklies:

In order for his results to reach the ‘right people’, Crookes felt that his paper had to appear in the pages of Nature, and not just Chemical News.

Interestingly, Rutherford also did not make use of another weekly publication, Science, which also had a correspondence column (‘Discussion and correspondence’) and whose New York editorial offices were closer to Montreal than Nature's London offices. Nor did Rutherford seek to publish his work in Canadian journals, even though his submissions could have reached those journals faster than they could reach journals in Great Britain. Rutherford's Britain-focused publishing strategy suggests that in addition to concerns about priority and prestige, Rutherford also sought to reach the right national audience. Rutherford's personal correspondence reveals that he felt Montreal was distant both geographically and intellectually from the centres of the physics world. In March 1901, Rutherford wrote to J.J. Thomson to seek advice on whether he should apply for the chair of physics in Edinburgh, recently vacated by the retirement of Peter Guthrie Tait. The letter acknowledged the excellent facilities at McGill but expressed some frustration at Montreal's distance from other scientific centres:

Rutherford ultimately decided not to apply for the Edinburgh chair, reasoning that the field of candidates was likely to be quite large and would include some of Tait's former protégés. But it appears that his feelings about his ‘colonial appointment’ did not change significantly over the next few years. In 1906, Rutherford again brought up his feeling of isolation when telling his mother of the offer at Manchester:

Rutherford's career goals likely explain his reluctance to direct his work to North American periodicals, even if those periodicals might have been able to get his work into print more quickly than British periodicals. Although Canada was a self-governing British colony, that did not guarantee that British professors back in the ‘home country’ would be aware of papers published in Canadian journals. Correspondence in Lockyer's personal papers suggests that there was a strong feeling in the Canadian scientific community that their scientific accomplishments did not always receive their due in the United Kingdom. Rutherford may have been concerned that publishing in North American journals would cause his work to be overlooked in Britain and in Europe.Footnote ⁴⁹ Publishing in British journals increased the likelihood that Rutherford's research would be read by radioactivity physicists in Europe's scientific centres. It also helped ensure that Rutherford's name was familiar to British universities who might be looking for a new professor of physics. Notably, prior to moving to Manchester, Rutherford turned down offers of physics professorships from Victoria University College in New Zealand, the University of Western Australia, and Columbia University in New York, suggesting that his true goal was to return to the United Kingdom.Footnote ⁵⁰

Radioactivity, Rutherford and changes in Nature

Rutherford's use of Nature affected not only his own career but the journal as well. Lawrence Badash argues that Rutherford ‘transformed the letters-to-the-editor section of Nature from one of genteel comments on scientific activity and reports of the first robin of spring, to announcements of the greatest fundamental importance and hard-hitting scientific controversy’.Footnote ⁵¹ This observation is not entirely accurate – Nature was a forum for ‘hard-hitting scientific controversy’ well before Rutherford started contributing, and many of those discussions were far from ‘genteel’.Footnote ⁵² However, Rutherford did make a significant mark on Nature by establishing the ‘Letters to the editor’ column as a major venue for priority claims, setting it apart from other scientific weeklies in Great Britain.

When prolific nineteenth-century contributors such as George J. Romanes, E. Ray Lankester or John Perry composed letters to the editor of Nature, they usually did so as part of a larger project, or as a focused commentary on someone else's work.Footnote ⁵³ The letters about their own work were generally counterparts to longer forthcoming papers. But Rutherford, like the researchers who had written to Nature about Röntgen rays, used letters to the editor as an end in themselves. Rutherford did not wait until he had a full paper in press for the Philosophical Magazine or the Proceedings before sending an abstract to Nature; he sent his most interesting experimental results immediately, both as a way of keeping his colleagues updated on his work and as insurance against being scooped as he had been in 1899. During his years at McGill, Rutherford wrote frequent letters to Nature filled with data and experimental observations about the heating effects of radioactivity, the amount of helium emanating from radium, the dependence of radioactivity on the concentration of radioactive materials, and the electrical charge on the alpha rays emitted from radium.Footnote ⁵⁴ These frequent research updates from one of the world's pre-eminent radioactivity physicists made Nature indispensable to anyone working on radioactivity – not just in Britain, but in Canada, the United States, Paris, Berlin and Vienna. Rutherford would continue submitting letters even after returning to the United Kingdom, albeit less frequently than he had before, suggesting that his use of Nature was still part of his publishing strategy but no longer as vital a part as it had been when he worked at McGill.Footnote ⁵⁵

Rutherford's personal correspondence reinforces the impression that Nature played a significant role in spreading news of the latest radioactivity research, especially among researchers living outside Europe. In the correspondence between Rutherford and the American physicist Bertram Borden Boltwood, for example, both men frequently mentioned Nature both as a place to print their own articles and as an important source of information about others’ research.Footnote ⁵⁶ Boltwood, who obtained his PhD at Yale in 1897, was arguably the most important radioactivity physicist in the United States.Footnote ⁵⁷ Boltwood began his career as a consulting chemist, working out of his own private laboratory in New Haven. He became interested in identifying the steps in the radioactive decay series and charting how a radioactive material's elemental identity changed as it emitted alpha, beta and gamma rays. He continued this work after being appointed as an assistant professor of physics at Yale in 1906. Like Rutherford, Boltwood was struggling with the disadvantages of being at a distance from major radioactivity research centres like Paris and Cambridge. Nature proved invaluable both as a fast source of pertinent abstracts and as a place to publish his own work. In an April 1905 letter to Rutherford about his work on the radioactive decay series, Boltwood wrote, ‘I have held up this letter somewhat, hoping to find some details of the R.S. paper on the new (?) element “which gives off thorium emanation” in the Nature which came last night’.Footnote ⁵⁸ A 1906 letter from Boltwood illustrates the American's practice of sending preliminary results both to American journals and to Nature. Boltwood wrote to share some new work on the radioactive decay series. He was pleased with his results and told Rutherford, ‘I have sent off a brief communication to the Editor of Nature and a note for the December number of the Am. Jour [American Journal of Science]’.Footnote ⁵⁹ Similarly, Rutherford frequently referred to recent pieces in Nature when discussing scientific matters with Boltwood. In June 1904 he assured Boltwood that Soddy's recent findings in Nature did not disprove Boltwood's own theories, writing, ‘I would not lay any especial stress on negative results of attempts to grow radium as in Soddy's letter to Nature’.Footnote ⁶⁰ Rutherford's letters also refer to sending early results to Nature; in October 1906, for example, he wrote, ‘I have done a few expts. recently which show that the emanations are completely absorbed in cocoanut charcoal at ordinary temperatures … You will see an account in Nature of the same in a week or so’.Footnote ⁶¹ Even after Rutherford's return to England, Nature continued to feature heavily in the letters between Rutherford and Boltwood.Footnote ⁶²

While the Curies remained at most an ephemeral presence in Nature, other international radioactivity scientists followed Rutherford, Soddy and Boltwood into the pages of Nature. The most notable among these was the German chemist Otto Hahn, a future Nobel Prize-winner (for the discovery of uranium fission) who studied at McGill with Rutherford in 1905–1906. Like Rutherford and other anglophone colleagues, Hahn soon adopted the practice of writing to Nature about interesting preliminary results.Footnote ⁶³ This was likely due to Hahn's desire to keep his English-speaking colleagues updated on his work in Germany, but also speaks to a perceived underdevelopment of radioactivity research in Germany. In June 1907, for example, Hahn wrote to Rutherford to share the good news that he had passed his examinations to become a privatdozent (an instructor at the university level), which he attributed to the fact that his examiners ‘were so terror stricken that they asked only some simple radioactive questions about the matter and did not want to hear anything else’. In the same letter, Hahn also spoke of feeling ‘lonely among all these chemists who don't really believe in radioactivity’ now that he had returned to his native Germany.Footnote ⁶⁴

At this point, we might wonder whether Rutherford and his fellow radioactivity physicists were unique in using the ‘Letters to the editor’ in this way. Another new science, genetics, provides a useful point of comparison. Between April and July 1900, three European scientists – Hugo de Vries in Amsterdam, Carl Correns in Munich and Erich Tschermak in Vienna – each published a paper in a German botanical journal, the Berichte der deutschen botanischen Gesellschaft, detailing experimental work on heredity and citing the work of an obscure Austrian monk named Gregor Mendel.Footnote ⁶⁵ Mendelism found a champion in Britain in the form of William Bateson, a Cambridge botanist and fellow of the Royal Society. In his efforts to spread the Mendelian theories of heredity, Bateson frequently engaged in barbed debates with biometricians W.F.R. Weldon and Karl Pearson, who argued that the statistical evidence in favour of Mendel's theories was inadequate.Footnote ⁶⁶

Genetics and radioactivity had much in common. Both were new fields of research, both were international sciences with communities of practitioners across Europe and North America, both were rapidly advancing at the beginning of the twentieth century. Given these similarities we might expect that geneticists would also use Nature's ‘Letters to the editor’ to announce their most recent work, but a quick examination of the parties involved in discussions about Mendelism in Nature reveals that despite the excitement surrounding the field, geneticists before the First World War did not use Nature to establish priority for their work. When we compare Bateson's use of the ‘Letters to the editor’ with Rutherford's, for example, we see that Bateson did not use the column to announce new results, as Rutherford did. Instead, Bateson wrote ‘Letters to the editor’ to disparage his opponents and criticize recent anti-Mendelian scientific papers, a pattern of contribution more consistent with nineteenth-century contributors like George J. Romanes or E. Ray Lankester.Footnote ⁶⁷ Furthermore, despite the wide international reach of genetics, the scientists writing to Nature about Mendelian inheritance were all living and working in the United Kingdom.Footnote ⁶⁸ Geneticists from outside the United Kingdom were not represented in these discussions. Why was genetics so different from radioactivity in the way its practitioners engaged with Nature?

The important difference between the two fields seems to have been how concerned their practitioners were with priority. In Britain, Germany, France and the United States, geneticists were struggling for national support and recognition of their new discipline – university positions, laboratory space and government support were all at stake.Footnote ⁶⁹ Geneticists were therefore less concerned than radioactivists about establishing priority over international rivals and more focused on establishing the value of their theories within their own national contexts, which is likely why Bateson used Nature to criticize his scientific enemies. Furthermore, if we return our attention to radioactivity, we see that the most frequent international contributors to Nature were researchers who corresponded frequently with Rutherford, and, in particular, men like Hahn who had studied for a time in his laboratory. Scientists who spent their careers in their native countries – for example Marie Curie or Stefan Meyer – seldom contributed to Nature. In contrast to radioactivity, foreigners rarely came to work in British genetics laboratories in the early twentieth century. In Britain, Germany, France and the United States, geneticists were struggling for national support and recognition of their new discipline, which may have dampened enthusiasm for sending their students and papers abroad. The contrasting example of genetics strongly suggests that Rutherford and the radioactivity community were unique in their use of the ‘Letters to the editor’ prior to the First World War.

Interwar physics: the Rutherford–Bohr–Copenhagen network

In the late 1910s and early 1920s, Nature's ‘Letters to the editor’ continued to follow the pattern we have seen thus far in this article – international scientists contributed a handful of letters, but the column was still heavily dominated by British contributors. Nature's discussion of relativity provides a helpful example of this trend. Although little was published in Nature about relativity prior to the First World War, the journal was a major host of discussions about relativity following Arthur Eddington's eclipse expedition in 1919. The relativity discussions in Nature, however, were almost entirely confined to British participants like Eddington, Oliver Lodge, Norman R. Campbell and Herbert Dixon.Footnote ⁷⁰ Even the special issue of Nature devoted to the discussion of relativity contained contributions from only three foreign sources – Einstein himself, the German mathematician Hermann Weyl and the Dutch physicist Hendrik Lorentz.Footnote ⁷¹

In the field of quantum mechanics and atomic physics, however, the material in Nature continued building on the international trends we saw in radioactivity research. Rutherford continued contributing, as did his colleagues at the Cavendish Laboratory (where Rutherford moved in 1919), but international contributors took on a new prominence in the years following the First World War. The continued growth in international physics contributions was closely linked to the career of one of Rutherford's students: the Danish physicist Niels Bohr.

Bohr had come to Rutherford's laboratory in Manchester as a postdoctoral researcher in 1913, following his successful stint at the Cavendish Laboratory under J.J. Thomson. He returned to Denmark in 1913 and published his famous model of atomic structure later that year. At the beginning of the First World War, Bohr returned to Manchester as a reader, and while in Rutherford's laboratory he adopted the practice of sending preliminary results to Nature as a letter to the editor.Footnote ⁷² In 1916 Bohr accepted a professorship in theoretical physics at the University of Copenhagen; four years later, in 1920, the university approved the foundation of an Institute for Theoretical Physics, which would become one of the most influential scientific centres of the mid-twentieth century. Bohr also won the 1922 Nobel Prize in Physics for his work on atomic structures. He and Rutherford would remain close friends and frequent correspondents until Rutherford's sudden death in 1937.Footnote ⁷³

Bohr was one of the most prolific scientific mentors of the twentieth century, and Bohr's pupils followed their mentor onto the pages of Nature as Rutherford's pupils had followed him. Most of their pieces were letters to the editor and followed the pattern of using Nature's correspondence columns to establish priority for exciting results. Contributions from Bohr's research centre at Copenhagen were frequent in the interwar years.Footnote ⁷⁴ One especially noteworthy contribution from the institute was a 1923 letter co-authored by the Danish physicist Dirk Coster and the Hungarian physicist George Hevesy, announcing the discovery of one of the missing chemical elements Rutherford's student Henry Moseley had predicted. Coster and Hevesy proposed naming the element with atomic number 72 ‘hafnium’, in honour of Copenhagen.Footnote ⁷⁵

Bohr was not the only Rutherford protégé to make his mark on Nature during the interwar years. One of the most influential Nature papers of the 1930s was authored by the British physicist James Chadwick, who had followed Rutherford to the Cavendish Laboratory at Cambridge. In 1932, Chadwick read a paper by Irène Curie (Marie and Pierre Curie's daughter) and Frederic Joliot suggesting that gamma radiation from beryllium disintegration had the power to force the ejection of alpha and beta particles from lighter elements.Footnote ⁷⁶ Chadwick hypothesized that the emission from beryllium was in fact an as yet undiscovered atomic particle with a mass of one and a neutral charge. After three weeks of intense work with the beryllium emissions, Chadwick felt his suspicion had been confirmed and submitted a letter to the editor of Nature on the ‘Possible existence of a neutron’. The letter was printed on 27 February 1932.Footnote ⁷⁷ A great deal of material on neutrons would be published in Nature through to the end of the 1930s, drawn both by Chadwick's initial choice of Nature and by the growing international prominence of the ‘Letters to the editor’. Nature's letters about neutrons came from such diverse locations as Paris, Vienna, Chicago, Warsaw, Calcutta, Kiev, Leningrad, Moscow and Osaka.Footnote ⁷⁸

The Rutherford–Bohr–Copenhagen connection was also responsible for perhaps the most famous pre-war letter printed in Nature's pages. In January 1939, the journal received a submission from two Austrian-born physicists, Otto Frisch and Lise Meitner. Meitner's former colleagues in Berlin, Otto Hahn and Fritz Strassmann, had bombarded uranium nitrate with neutrons and discovered that their sample subsequently contained barium.Footnote ⁷⁹ Frisch and Meitner wrote a letter to the editor of Nature offering an explanation for what had occurred. They suggested that the uranium nucleus had, in fact, split in two, and they proposed a mechanism for how the nucleus could have split: the now-famous ‘liquid drop’ model of nuclear fission.Footnote ⁸⁰

Frisch was likely the one who suggested that the pair submit the piece to Nature. Although Meitner was known and respected in Britain – Nature published a congratulatory note on her sixtieth birthday, along with a glowing account of her scientific career – she had never published an article in Nature, preferring instead to direct her work to German scientific journals.Footnote ⁸¹ Frisch had been at Copenhagen since 1933, when Hitler's rise to power prompted him to leave his post at the University of Hamburg for one at Bohr's Institute for Theoretical Physics. He had co-authored many letters to the editor in Nature with his colleagues in Denmark and it seems likely that Frisch suggested Nature as the best journal for their theory given his previous familiarity with the ‘Letters to the editor’ column.Footnote ⁸² The case of Meitner and Frisch's famous letter further illustrates the impact of the Rutherford–Bohr–Copenhagen network on publication patterns in Nature.

This tactic of using Nature's ‘Letters to the editor’ to announce results eventually spread to those who were not Rutherford or Bohr students. The wide international range of the contributions about neutrons nicely illustrates the spread of this publishing strategy. This use of the ‘Letters to the editor’ also eventually spread to fields such as genetics, where (as we saw earlier) the contributors before the First World War had not used the ‘Letters to the editor’ to announce new work and had been almost entirely British. By the 1930s geneticists from such diverse locations as Prague, Helsinki, Berkeley, Princeton, Stockholm, Hamburg and Moscow were also sending their latest findings to Nature. Footnote ⁸³