In 1962, John Cockcroft (1897–1967) reflected back on the “Miraculous Year” (Annus mirabilis) of 1932 in the Cavendish Laboratory:
The father of nuclear physics. Rutherford (on the right) at Cavendish Laboratory.
“One month it was the neutron, another month the transmutation of the light elements; in another the creation of radiation of matter in the form of pairs of positive and negative electrons was made visible to us by Professor Blackett's cloud chamber, with its tracks curled some to the left and some to the right by powerful magnetic fields.”
Rutherford reigned over the Cavendish Lab from 1919 until his death in 1937. The Cavendish Lab in the 1920s and 30s is often cited as the beginning of modern “big science.” Dozens of researchers worked in teams on interrelated problems. Yet much of the work there used simple, inexpensive devices — the sort of thing Rutherford is famous for. And the lab had many competitors: in Paris, Berlin, and even in the U.S.
Mary Newton, 1896, a memento for Ernest to remember her while away from New Zealand. In 1898, on Thomson’s recommendation, Rutherford was made professor of physics at McGill University in Montreal, Canada. During his last years at the Canterbury College in Christchurch, Rutherford had met and fallen in love with his landlady’s daughter, Mary Georgina Newton. The couple had been engaged before Ernest left New Zealand. His new job allowed Ernest Rutherford to marry Mary Newton in Christchurch, New Zealand in 1900. The couple’s only child, a daughter named Eileen Mary, was born in 1901. Eileen would go on to marry Sir Ralph Howard Fowler, a British physicist and astronomer. Rutherford’s daughter died after giving birth to her fourth child in 1930, leaving him devastated.
It is tempting to simplify a complicated story. Rutherford directed the Cavendish Lab for 18 years, and yet many accounts focus exclusively on the dramatic year 1932, as John Cockcroft highlighted in the quote above.
A more complete account asks what else was happening in the lab in 1932, what was happening in the dozen years before that, and in the five years that followed. One also needs to know how the events at the Cavendish Lab stacked up against events in the rest of the physics world.
J.J. Thomson was appointed Master of Trinity College, Cambridge in 1919, and thus began Rutherford's remarkable final act in the story of nuclear physics.
Ernest Rutherford and Mary Georgina Rutherford
Thomson's new position demanded his full attention, so he resigned as Cavendish Professor and as director of the Cavendish Laboratory. A board of electors, including Joseph Larmor (1857–1942) and Arthur Schuster, chose Rutherford to succeed Thomson.
Rutherford shrewdly negotiated to be certain that Thomson would not interfere in the lab, but allowed him to keep a few rooms for himself, his assistant, and a few research students.
Thomson in turn made certain Rutherford was elected a Fellow of Trinity College, with rights “to dine there when I please.” (Eve, pp. 269–273). This promised peace between the two giants in the Cavendish Laboratory.
Ernest Rutherford 1909
It is often said that Rutherford had little time for research of his own when he moved to the Cavendish Laboratory in 1919.
True, he did have more administrative duties than at earlier stages in his career. Moreover, he did more for science beyond the lab, as president of the British Association for the Advancement of Science (1923) and of the Royal Society (1925–1930), as chairman of the Advisory Council of the government's Department of Scientific and Industrial Research (1930 on), and in 1933 he became president of the Academic Assistance Council.
Sir Ernest Rutherford and Eileen (Bay) de Renzie, outside cottage in Wales
The latter helped Jewish scientist-refugees displaced by Nazi policies in Germany. He was also asked to give many lectures, including four lectures per year as Professor of Natural Philosophy at the Royal Institution in London from 1922 on.
Rutherford studied the radiations emitted by radioactive substances and coined the terms alpha, beta and gamma
Nevertheless, Rutherford continued to investigate the nucleus. Rutherford's McGill period emphasized research on naturally occurring radioactive decay. In Manchester, it was the nuclear theory of the atom. And as Cavendish Professor he disrupted the nucleus.
Rutherford’s teacher, J.J. Thomson had discovered the electron 12 years earlier.
Rutherford brought this new field of research, the artificial disruption of the nucleus, with him from Manchester to Cambridge. He brought his equipment and radioactive materials along, but most importantly, he invited his former student, James Chadwick, to join him in further experiments.
Such experiments always involved a bit of “What will happen if we do this?” However, Rutherford had several clear questions and goals in mind. During the Great War and in early 1919, he and his assistant Kay tried systematically to “disrupt the nucleus.”
Rutherford the early years by Ian Cox & Mike Whittal
They quickly found in 1919–1920 that nitrogen and other light elements ejected a proton (Rutherford said “a hydrogen atom” rather than “a proton”) when hit with α (alpha) particles. Rutherford and his collaborators saw scintillations– flashes of light – when the high-speed particles hit a zinc-sulfide screen in a darkened room.
What was left behind in the target material? And what became of the α particle? This puzzle demanded close work.
Some historical accounts erroneously assert that Rutherford concluded that the nitrogen target captured the α particle (with a charge of 2 positive units) and emitted a proton (with its charge of 1 positive unit), which meant the target now had a nuclear charge of 8 instead of 7.
Ernest’s parents – James and Martha Rutherford. Ernest Rutherford was the son of James Rutherford and his wife Martha Thompson. Martha Thompson was originally from Essex, England while James Rutherford lived in the Scottish city of Perth. James and Martha immigrated to New Zealand when they were young. They met there and married in 1866. Ernest was born on August 30, 1871, in Spring Grove, near Nelson, New Zealand. He was the second of seven sons and fourth of twelve children born to them. James primarily worked as a farmer in New Zealand while Martha was an English school teacher. https://learnodo-newtonic.com/ernest-rutherford-facts
According to this telling, the nitrogen had become an isotope of oxygen and the alchemical dream of transmutation had been realized by physicists in the lab. If true, this discovery would have provided a dramatic entrance for Rutherford into Cambridge life. This was not Rutherford’s conclusion at the time.
On the contrary, Rutherford suspected something less dramatic in 1919. He limited his conclusion to identifying the hydrogen atom (or proton) that was ejected. Rutherford wrote (“Collision of α Particles with Light Atoms,” p. 586):
“From the results so far obtained, it is difficult to avoid the conclusion that the long-range atoms arising from collision of α particles with nitrogen are not nitrogen atoms but probably atoms of hydrogen.
If this be the case, we must conclude that the nitrogen atom is disintegrated under the intense forces developed in a close collision with a swift α particle, and that the hydrogen atom which is liberated formed a constituent part of the nitrogen nucleus.”
Rutherford took care in 1919 only to hypothesize the possible disintegration of the nucleus. He did not claim to demonstrate the transmutation of elements.
As Peter Galison notes in Image and Logic (1997, p. 118), Rutherford’s observations of scintillations revealed nothing more about the interaction of the α particle and the nitrogen nucleus.
Milorad Mladjenović, in his History of Early Nuclear Physics (1992, pp.157-162), traces the important steps in Rutherford’s 1919 experiments. While Rutherford had many suspicions about what happened to the nitrogen nuclei, he was careful to limit his conclusions to what experiment had established.
So where did the myth of Rutherford’s 1919 transmutation originate? Steven Krivit tells this story in his Lost History: Explorations in Nuclear Research, vol. 3, chapter 23.
He traces the beginning of the myth to newspaper articles in that year and then to Rutherford’s reaction in 1925 to results by his younger colleague, Patrick Blackett.
Krivit correctly credits Blackett with observations that showed the process of transmutation in action. For more detail on this fascinating story, see Krivit’s book.
Francis Aston is known as a researcher who worked mostly alone at the Cavendish Laboratory. However, his investigations of isotopes and very precise measurements of atomic weights were actually quite important to Rutherford’s nuclear research in the 1920s.
Another researcher at the Cavendish Laboratory, Francis W. Aston (1877–1945), provided critical aid to this research. Aston had been J.J. Thomson's assistant from 1909 until World War I and perfected the use of electric and magnetic fields to analyze moving, charged particles.
Aston developed the “mass spectrometer,” capable of precision separation of isotopes, techniques valuable in Rutherford's studies. (Isotopes are atoms with the same charge but with a different atomic weight.)
Aston received the Nobel Prize in Chemistry for this work in 1922. He maintained a research room in the Cavendish throughout Rutherford's professorship.
Pre-occupied with the composition of the nucleus in 1920, Rutherford was asked to give a prestigious lecture to the Royal Society of London.
With experimental experience no one else had, Rutherford speculated. He said that combinations of the ultimate particles — the proton and the electron — could produce as-yet undiscovered particles and materials.
A nucleus of mass 2 and charge 1 (2 protons bound closely to an electron, he said) would be an isotope of hydrogen. (We would now say this nucleus had 1 proton and 1neutron.)
Also possible, he suggested, was “an atom of mass 1 which has a zero charge.” (Eve, p.281). In short, Rutherford called for searches that ultimately yielded deuterium, the neutron, and other surprises.
This 1920 Royal Society lecture set much of the agenda for Rutherford and his lab for the rest of his life. Through the 1920s Rutherford, his personal assistant George Crowe, and Chadwick used α particles to probe and prod the nucleus: to determine its size, to measure the energy of emitted protons, and they investigated the “barrier of very high potential which retained the nucleus intact, while checking the ingress of a foreigner” (Eve, pp. 298–299).
They also searched unsuccessfully for more than 10 years for the neutron. To be sure, Chadwick and Crowe did much of the work, but Rutherford was always involved, asking questions, making suggestions, and celebrating or berating.
That explanation was really a kind of Compton effect on the proton, wasn't it? I'd looked at that and never said anything about it, but of course, did a lot of experiments about which I never said anything.
Some of them were quite stupid. I suppose I got that habit or impulse, or whatever you'd like to call it, from Rutherford. He would do some damn silly experiments at times, and we did some together.
They were really damned silly. But if we'd gotten a positive result, they wouldn't have been silly. But he never hesitated. At times he would talk in what seemed to be a rather stupid way.
He would say things which put down on paper were stupid or would have been stupid. But when one thought about them, you began to see that those words were inadequate to express what was in his mind, that there was something in the back which was worth thinking about.
I think the same thing would apply to some of these experiments that I have said were silly. There was always just the possibility of something turning up, and one shouldn't neglect doing, say, a few hours' work or even a few days' work to make quite sure...
The Cavendish Laboratory in the 1920s and 30s was a busy and crowded place. In addition to Rutherford, Chadwick, Aston, and Thomson, each year roughly thirty research students and a number of visitors were busily pursuing diverse researches.
Some teams investigated problems related to Rutherford's and some researched other problems. Some Cavendish researchers, such as C.T.R. Wilson (1869–1959), located their work outside the lab. Some outsiders, such as the theoretician Ralph Fowler (1889–1944) of the Department of Mathematics, kept a room in the lab.
Mark Oliphant (1901–2000), an Australian who came to the Cavendish Laboratory as a research student in 1927, described the classroom experience of new students: Aston read directly from his book on isotopes. Arthur Eddington (1882–1944) discussed relativity, speculatively, and “almost without mathematics.”
Douglas Hartree (1897–1958) provided thorough if pedantic lectures on quantum theory, while Nevill Mott (1905–1996) gave excellent quantum lectures. C.T.R. Wilson was so timid a speaker on atmospheric electricity that few students came to any lectures after the first.
According to Oliphant: “...the lecturer himself was...clearly embarrassed by his inability to express himself.” On the other hand, John A. Ratcliffe's (1902–1987) discussions of the ionosphere “were the most lucid and best presented lectures I have attended.” (Oliphant, p. 24).
Rutherford also lectured on the atom, with great enthusiasm, but not always coherently or well prepared. Oliphant relates one time when Rutherford reached an impasse in a lecture and said to the class: “You sit there like a lot of numbskulls, and not one of you can tell me where I've gone wrong.” (Oliphant, p. 26).
Despite Rutherford’s fabled preference for small, improvised apparatus, he also supported the development of high-voltage equipment. This equipment allowed new research in high energy particles and at ultra-low temperatures. Credit: British Information Services, 30 Rockefeller Plaza, New York, NY, courtesy AIP Emilio Segrè Visual Archives.
Research groups, led by strong individuals, worked on many questions and new devices around the Cavendish Laboratory. Patrick Blackett (1897–1974), at the lab since 1919, directed improvements in cloud chambers for nuclear and cosmic ray research.
Aston concentrated on a new, more precise mass spectrometer. Peter Kapitza (1894–1984) developed strong magnets and studied the effects of strong fields on materials. Mark Oliphant, John Cockcroft, and E.T.S. Walton (1903–1995) explored ways to accelerate charged particles.
Also in the late 1920s, Rutherford encouraged the search for electronic means of detection of nuclear events to replace the scintillation method.
C.E. Wynn-Williams (1903–1979) led the way with his “scale-of-two counter,” but many members of the lab were inspired by the success of Hans Geiger and Walther Müller's electronic radiation detector — the Geiger–Müller tube — in 1928. Wynn–Williams' detectors proved essential in nuclear research in the 1930s.
A last example of a research group was far afield from nuclear physics. Its leader, Ratcliffe, came to the Cavendish Laboratory as a student in 1921 and began research in 1924. When E.V. Appleton (1892–1965) left in the mid 1920s, Rutherford asked Ratcliffe to direct work in radio and atmospheric geophysics.
His group contributed greatly to ionospheric physics and later to radioastronomy. This work shared something with nuclear physics: a great reliance on electronics. Hence, although the topics differed, everyone benefitted from advances in instrumentation in the Cavendish Lab.
Rutherford's researchers produced three major nuclear developments in 1932. In February, Chadwick announced the detection of the neutron. In April, John Cockcroft and E.T.S. Walton disrupted the nucleus using artificially accelerated protons.
And late in the year, Patrick Blackett and Giuseppi Occhialini (1907–1993) demonstrated the existence of the positron. What led to these remarkable achievements?
Chadwick had been seeking experimental evidence of the neutron throughout the 1920s. Although he had other successes during the decade, every attempt to detect the neutron was a dead-end until 1932. This should not be a surprise.
With no electrical charge, a neutron would not show itself in the same ways that charged particles do.
Rutherford and Chadwick's systematic study of nuclear disintegration in their first year at Cambridge, combined with Aston's precise mass spectrometry work, attuned them to paying close attention to atomic weights in “nuclear reactions.”
When Walther Bothe (1891–1957) and H. Becker observed some unusually penetrating radiation in 1930 and when in early 1932 Irène (1897–1956) and Frédéric Joliot-Curie (1900–1958) asserted similar results to be due to γ (gamma) rays, Rutherford and Chadwick just didn't think that the sums added up (Hendry, pp. 7–9).
Chadwick set off to test this γ-ray hypothesis. He used the same radiation from beryllium as the others did, aimed the radiation at paraffin (a rich source of proton ejecta), measured the range of these protons, and also measured how these rays from beryllium impacted various gas atoms.
He did, however, have better detection equipment. He concluded that γ-rays could not produce these effects and that the beryllium radiation must be a neutrally charged particle of roughly the mass of a proton. He had found evidence of the neutron.
This was, to be sure, indirect evidence. He had not “seen” a neutron, but the effects were consistent with such a particle. Chadwick announced the “discovery” of the neutron in a paper sent to the journal Nature on 10 February 1932. (The experiment was somewhat more complicated than explained here, but this discussion catches the most important points.)
The second great event of the Annus mirabilis of 1932—the first use of a particle accelerator to produce a nuclear disintegration—had also been years in the making.
Since Rutherford's earliest work, the main source of fast charged particles had been the decay of naturally occurring radioactive materials, such as radium. And the most common particle emitted in these experiments was the α particle, or helium nucleus.
Cockcroft, Rutherford, and Walton in 1932, shortly after they accelerated protons against a lithium target, splitting the lithium nucleus into two alpha particles, i.e., helium nuclei.
This demonstrated not only the “transmutation” of elements, but also Einstein's formula E=mc2, since a slight loss of mass produced energetic alpha particles. Credit: UK Atomic Energy Authority, courtesy AIP Emilio Segre Visual Archives.
Like other physicists in the 1920s, Rutherford wanted to find ways to accelerate electrons, protons, and α particles artificially. That is, with a machine.
Indeed, he had urged attention to particle accelerators in his 1927 Presidential Address to the Royal Society. True, he did not want to spend a lot of money to do it and he discouraged building a machine bigger than necessary.
Nevertheless, he wanted a particle accelerator. As he said in that address:
“It has long been my ambition to have available for study a copious supply of atoms and electrons which have an individual energy far transcending that of the α and β-particles from radioactive bodies.
I am hopeful that I may yet have my wish fulfilled, but it is obvious that many experimental difficulties will have to be surmounted before this can be realised on a laboratory scale.”
With arrival in the Cavendish Lab of new students with engineering background, this dream was soon achieved.
Listen to Dr. Phillip Dee talk about the historical significance of Rutherford's work:
This is a generality which is of historical importance, here. It's a generality, and that is, a great factor in Rutherford's successful running of the Cavendish, you know, was that when he saw the clouds breaking, everybody was pulled into it, you know.
He was a great general in that sense, because if Rutherford got an idea that something was going to work or that something was possible, all the resources were thrown into that gap.
It was like an Army broaching the barriers, if you see what I mean, so that I'm not wanting to say I was an important factor in this, but I'm saying that when things like the neutron or the artificial disintegration came along, all resources, however trivial, would be pulled in, and I was one of these things that were pulled in, I would say.
That's how it happened. That's what took me into the Cavendish, as distinct from remaining working with C.T.R. It was just the fact that this was Rutherford's behavior, you know.
Merle Tuve (1901–1982) and Gregory Breit (1899–1981) in the U.S. worked on a Tesla coil and a Van de Graaff generator to produce high voltages to accelerate charged particles.
Meanwhile at Cambridge, T.E. Allibone (1903–2003) (from the Metropolitan-Vickers electrical company) attempted a similar machine.
There were others, but the best known is Ernest Lawrence (1901–1958), who first tried to build a linear accelerator, and then built his famous cyclotron in 1930.
John Cockcroft, with a degree in electrical engineering from the University of Manchester, came to Cambridge in 1922. In 1924 he joined Kapitza in his industrial-scale effort to produce large magnetic fields. Cockcroft also was considering Rutherford’s accelerator challenge.
He was joined in 1927 and 1928 by T.E. Allibone and Ernest Walton. Together and alone, they considered a circular accelerator and others of several designs but could not overcome design difficulties or the limitations of a lab that was not yet supplied with a standard high-voltage alternating current.
Work was sped up at Cambridge after a visit by the Russian theoretical physicist George Gamow (1904–1968) in 1929. Cockcroft recognized the implications of Gamow’s theoretical work. He concluded that a 300,000 volt proton accelerator could penetrate the nucleus of target material and might produce a nuclear reaction.
Now the Cambridge team had only to design and build the machine! It's a long story, but by 1932 Cockcroft had been joined in the experimental work by Walton and they were ready to try to disintegrate atoms. Cockcroft and Walton were always looking for leaks in the evacuated machinery.
On 13 or 14 April, Ernest Walton had observed scintillations on a screen, indicating that their accelerated protons, impinging on lithium, had split the lithium nucleus and produced two α particles.
The last dramatic development of 1932 at the Cavendish was the demonstration by Patrick Blackett and Giuseppe Occhialini of the existence of the “positive electron” or positron. Usually the discovery of the positron is credited to Carl Anderson at California Institute of Technology.
Although Blackett and Occhialini's research was contemporaneous with Anderson's, Blackett had held back his announcement until he had solid evidence. This was typical of a Rutherford team.
Patrick Blackett left the Cavendish Laboratory in 1933 to accept a professorship at Birkbeck College, London, then in 1937 to Manchester.
There he was Langworthy Professor, Rutherford's former position. He later contributed to Operational Research and to paleomagnetism. Credit: University of Cambridge, Cavendish Laboratory.
The solid evidence consisted of cloud chamber photographs that showed two particles spiraling in opposite directions from a common point.
Blackett and Occhialini had the advantage of Blackett's decade of improvement of the cloud chamber and of Occhialini's familiarity with a technique developed in Italy by his mentor, Bruno Rossi (1905–1993).
Rossi's technique used two Geiger-Müller counters in a straight line to trigger an action, when a charged particle tripped both counters in quick succession.
Blackett and Occhialini put these two ideas together. In their device, cosmic rays (or charged particles in nuclear experiments) took their own pictures.
Their experiments now produced photographic evidence 80% of the time (Hendry, pp. 7–30, passim). Because Anderson published his announcement first, he received the 1936 Nobel Prize in Physics for the discovery of the positron.
There is much more to each of these three stories from the Annus mirabilis of the Cavendish Laboratory. This telling, however, gives you some idea of the excitement enjoyed by Ernest Rutherford and his researchers in 1932.
It should be remembered, however, that this excitement came after 12 years of hard work.
https://history.aip.org/exhibits/rutherford/sections/atop-physics-wave.html
Ernest Rutherford was born in Brightwater, near Nelson, New Zealand, in 1871. He was the fourth child and second son of 12 children, to James Rutherford, a mechanic, wheelwright, engineer, flax-miller and farmer and his wife, Martha Thompson, a school teacher before her marriage.
Both parents were keen that their children gain an education, and were supporters of the small local schools where Rutherford and his brothers and sisters began their schooling.
Martha ensured the Rutherford children completed their homework with the dictum, “All knowledge is power.”
From an early age Rutherford was distinguished at school for his arithmetical abilities and his scientific curiosity. Both qualities were encouraged by his early teachers, Harry Ladley at Foxhill and Jacob Reynolds at Havelock School.
Reynolds gave extra lessons in Latin and algebra for children of above average ability, including brothers Ernest and Jim Rutherford.
Rutherford’s early education, from school, from his family and from exploring the local farms and countryside with his siblings, awakened his interest in science and developed the the keen observational skills that are essential for the scientific mind.
A school science text-book told of a method for determining the distance of an enemy’s cannon, a method which Rutherford adapted to local surroundings during an electrical storm at Foxhill.
As Eugene Grayland recounts in Famous New Zealanders in a reconstruction of an anecdote from Rutherfrod’s childhood:
“James Rutherford, who had got out of bed to check on the storm, was surprised, more so when he heard his son talking to himself softly.”
‘Ernest, what’s up, my boy?’ he called out.
‘I’m counting,’ the boy called back.
‘Counting?’
There was a rumble of thunder which shook the house.
‘Yes. If you count the seconds between the flash and the thunder clap and allow 1,200 feet for each second for the sound to travel, you can tell how close you are to the storm centre.’ “
Appropriately, Rutherford’s first recorded experiment was a cannon constructed from the brass tube of a hat-peg with a marble for a ball and a dose of gunpowder to ignite the device.
It was not the best example of Rutherford’s experimental savvy, the resulting explosion failing to deliver the marble to the target twenty metres away, but succeeding in destroying the cannon.
The Rutherfords were a close-knit family, gathering around the piano to sing songs; forging a life with few amenities in the isolated and rugged landscape.
Though two of the brothers drowned in a childhood accident and another died as an infant, the life of the Rutherford siblings was filled with the curiosity-satiating distractions of growing up in the New Zealand outdoors.
There were the stimuli of farm-life: poaching eggs from bird’s nests, orchard raiding, swimming in the Wai-iti river, shooting Kereru pigeons fat from feeding on berries, calculating the level for storage ponds at the flax-mill.
Earning enough to feed the family was a struggle for James Rutherford at times. He ran a farm and flax-mill at Foxhill, and another at Pelorus when the family moved there, in 1883. In 1885 he turned to saw-milling, manufacturing railway sleepers for the Government.
However due to an economic downturn his contract was cancelled (while he was recovering from an accident which left him with five broken ribs) and he had to leave the family to look for new opportunities in the North Island.
He founded a steam driven flax-mill in Pungarehu, Taranaki, employing twenty people, where he moved the family in 1888.
In the school holidays Rutherford busied himself with farm chores, helping out on the farm or at the mill.
He had distinguished himself from his earliest days at school, but it took two attempts for him to win an education board scholarship and follow his older brother, George, to Nelson College.
For children of less-than-wealthy parents a scholarship was one of the few options available with which to obtain further learning. Rutherford attended Nelson College as a boarder for three years, and came under the tuition of William Littlejohn, who taught him mathematics and elementary science.
He topped his class in every subject in his final year and, after sitting the exam twice, won one of ten nationwide Junior Scholarships. In his final year he was also head boy, dux, and was a forward in the rugby First XV.
In 1890, he enrolled at Canterbury College, University of New Zealand (now The University of Canterbury). At Canterbury College he continued to play rugby and took part in the student Dialectic Society (a debating club) and the Science Society.
In 1892, Rutherford completed a Bachelor of Arts degree from Canterbury College and won the only available Senior Scholarship for mathematics.
This made it possible for him to return to university for an Honours year, completing a Master of Arts with double First Class Honours in Mathematics and Physics.
At Canterbury he was taught by Professor Alexander Bickerton, whose “genuine enthusiasm for science gave a stimulus to me to start investigations of my own”, as Rutherford would credit later.
It was in 1893 that his talent for original experimentation and research began to manifest itself: a penchant for creating innovative experiments to solve problems.
The findings in his first year’s research were based on his invention of a machine that could measure time differences of up to hundred-thousandth of a second. With this device he demonstrated that it was possible for iron to be magnetized by high frequency currents.
In 1894, Rutherford completed a Bachelor of Science in Geology and Chemistry and in 1895 was awarded an Exhibition of 1851 Science Research Scholarship (but only after the top-ranked candidate withdrew).
He elected to work as a research student at the Cavendish Laboratory, University of Cambridge, under Professor J.J. Thomson.
The Professor was studying the conduction of electricity in rarefied gases, which led to his 1897 discovery of the electron. This was the first object to be discovered that was smaller than an atom.
At Nelson College and Canterbury College, fostered by Bickerton, Rutherfordhad been no more than an excellent student.
With his move to Cambridge, on a scholarship designed to benefit young graduates from the outposts of Empire, his gifts were to be fully recognised (Rutherford was amongst the first “foreign” students to be admitted to Cambridge, without going through the undergraduate system).
Family anecdote recalls that Rutherford was working on the farm when he received news of the scholarship: “That’s the last potato I will ever dig” he remarked.
Once in Cambridge, he amazed Thomson with his enthusiasm, tenacity and fresh approach.
As Campbell has written, Rutherford went to Cambridge with a reputation as an innovator and inventor, and distinguished himself in several fields, initially by divining the electrical properties of solids and then using wireless waves as a method of signalling:
“Rutherford was encouraged in his work by Sir Robert Ball, who had been scientific adviser to the body maintaining lighthouses on the Irish coastline; he wished to solve the difficult problem of a ship’s inability to detect a lighthouse in fog.
Sensing fame and fortune, Rutherford increased the sensitivity of his apparatus until he could detect electromagnetic waves over a distance of several hundred metres.
Thomson […] quickly realised that Rutherford was a researcher of exceptional ability and invited him to join in a study of the electrical conduction of gases. The commercial development of wireless technology was thus left for Guglielmo Marconi.”
Rutherford’s advances in the study of radioactive atoms (most notably discovering that two different emissions, named alpha and beta rays, emanate from radioactive atoms) and his genius for experimentation secured his reputation, even compared to his brilliant mentor Thomson.
In 1898, at the age of 27, he moved to McGill University in Montreal, where he held the position of Professor of Physics.
The McGill years, from 1898 to 1907, were significant for two major developments. Firstly, Rutherford was finally on a secure enough financial footing to marry his long-time fiancé, Mary Georgina Newton.
She was the daughter of Mary Newton, who was Rutherford’s landlady in Christchurch, prominent in the movement which saw the women of New Zealand granted the vote in 1893.
Rutherford and Mary were married in 1900 in Christchurch. Their only child, Eileen, was born in 1901.
Secondly, it was at McGill that Rutherford made the first of his three major discoveries. Assisted by chemist Frederick Soddy, he unravelled the mysteries of radioactive atoms.
He rejected the popularly accepted belief that elements were immutable, which the word atom itself implies. It derives from the Greek “tomos“, meaning to cut, and “a” meaning not; therefore an atom is something unsplittable.
Rutherford demonstrated that in fact some heavy atoms spontaneously decay into slightly lighter, and chemically different, atoms. His book on this subject, Radioactivity, was published in 1904, followed by others in 1906 and 1930.
It was this discovery and his work on the chemistry of radioactive materials, that led to him being awarded the Nobel Prize in Chemistry in 1908 for his “investigations into the disintegration of the elements, and the chemistry of radioactive substances.”
While at McGill, Rutherford also developed a range of devices including one for measuring vibrations caused by streetcars and another for trains to signal to stations using wireless telegraphy. Much of the apparatus he developed is today housed at McGill’s Rutherford Museum.
In 1907, at the age of 36, Rutherford was lured back to England to become Professor of Physics at Manchester University.
Dissecting The Atom. In 1907, Rutherford began a debate with physicist Antoine Becquerel on how alpha particles, reacted when they were ejected from radioactive material.
Discovering that they tended to bounce off air molecules, he surmised that there had to be something at the centre of atoms to deflect them.
He tested his assumptions by bouncing alpha particles off a sheet of gold leaf and determined that the most powerful part of an atom was a very small, heavy, core at its centre, an electrical charge concentrated at a point – the nucleus.
This was surrounded by a cloud of electrons made up of an opposing electrical charge.
This concept of opposite charges which, as David Eliot Brody and Arnold R Brody noted, “marks the beginning of the modern understanding of the structure of the atom”, was Rutherford’s second great discovery. As Campbell says, “the nuclear model of the atom had been born”.
This orbiting model was the most revolutionary idea of Rutherford’s career, as Nigel Costley, writing in the Sunday Star Times, relates:
“Prior to Rutherford the best model of the atom was J.J. Thomson’s plum pudding which pictured it in a thin cloud of positive charges, with electrons dotted amongst it, like so many raisins in a plum pudding.”
“Rutherford’s experiments showed the pudding idea was wrong, replacing it with a solar system model. An incredibly dense positively charged nucleus lay at the centre which was tiny compared to the whole atom; like a postage stamp in a football field.”
“Through his studies of radioactivity in the 1890s, he discovered alpha particles which became, in his skilled and determined hands, the chief weapon in prising out the secrets of the sub-atomic world.
These particles were known to be 7400 [closer to 7273] times heavier than electrons and when he fired them in huge numbers at a strip of very thin gold foil, it was expected they would effortlessly pass straight through.”
“However a surprisingly high number were deflected […]. Rutherford was astonished: “It was as if you fired a 15-inch shell at a sheet of tissue paper and it came back to hit you.” From these deflections he was able to calculate the size of the nucleus.”
During World War I, Rutherford worked on acoustic methods of detecting submarines and developed several new technologies. He then drew on a lifetime’s strengths in practical experimentation for the third great breakthrough of his career.
Radioactivity had shown that some atoms spontaneously split, but in 1917 (reported 1919) the committed alchemist Rutherford, as McLauchlan writes, “detected the transmutation of one elementary material, nitrogen, into another, oxygen, which was induced artificially when the nitrogen atom was bombarded by the natural alpha articles of radium.”
Rutherford was, as he describes the process himself with typical understatement, “playing with marbles.” He was using alpha particles to eject protons from materials containing hydrogen when he found the same thing happened in nitrogen (which doesn’t contain hydrogen).
But more importantly the proton came out at higher energy than it could have received by collision.
In that year Rutherford had written to Niels Bohr that, “… I am also trying to break up the atom by this method … Regard this as private.”
Effectively Rutherford had “broken up” or split the atom. With this experiment, he was the first human to create a “nuclear reaction”, though a weak one.
From Rutherford’s first discovery onwards he had swept away accepted models of the stable atom, altered the course of modern science and made possible the development of nuclear physics.
Once more Rutherford’s demonstrations had changed the way we viewed and conceived of the world, breaking through the gross world of matter into the subtle world of atoms.
...
Rutherford returned to Cambridge’s Cavendish Laboratory as Director, in 1919, and became well known for a personality to match his achievements, mentoring and directing others towards great discoveries.
Prof. S. Devons in A Hundred Years and More of Cambridge Physics: Rutherford’s Laboratory recounts:
“Cambridge, and the Cavendish Laboratory especially, was an established, renowned centre of science. In the early 1930’s its lustrous reputation was as high as ever. These years were indeed the “golden age” of the Cavendish …”
“His influence there seemed a wholly natural phenomenon. Benevolent guidance, leadership and intellectual authority flowed from him, and loyalty was returned.
One would no more question his influence on those around him than one would that of the sun on the satellite planets. Rutherford, the Cavendish Professor, was the centre of light and warmth and life. It was the natural order of things. “
Michael Kelly (one of the many New Zealanders who followed in Rutherford’s wake to study physics at Cambridge and now a world leader in the field of solid-state physics) has said that because of his tenacity, Rutherford was popularly known as “crocodile”.
This was because, as well as connoting the father of the family, a crocodile can never see its tail. “It always looks forward and that’s how he was … he would make bold imaginative leaps at what might be going on before setting up the experiments to check it.
There are other people who work in much more formalistic ways, but he had an idea on the main chance.”
Rutherford set high standards of research at Cambridge. Michael Kelly again: “Rutherford’s style of doing research set the tone for much of the experimental work done at Cambridge. His was very much a sealing wax and cotton style – ‘let’s have a go’.”
In Richard Rhodes’ book, The Making of the Atomic Bomb, one of Rutherford’s protegees, James Chadwick, summed up his mentor as follows: “Rutherford’s ultimate distinction was ‘his genius to be astonished’.”
This key to Rutherford’s thought and approach reflects Rutherford’s background as much as his personality: growing up in the rough and ready New Zealand backblocks, he was relatively free of the social constraints and acceptance of intellectual assumptions that marked the more genteel culture of British physicists.
What Rhodes has called the “braiding of country-boy acuity with a profound frontier innocence” made Rutherford free of preconceptions and independent of accepted theories and assumptions, leading to his originality as a thinker and experimenter.
A fellow student in his early days at Cambridge noted: “We’ve got a rabbit here from the Antipodes, and he’s burrowing mighty deeply.”
In his study of Rutherford’s life, Nigel Costley reports that:
“…you could tell when work was going well in Rutherford’s laboratory: he strode about singing a spirited rendition of “Onward Christian Soldiers.”
His character, full of hearty good humour interspersed with imperious commands, was more that of a boisterous colonial farmer than the world’s leading scholar.
Yet by virtue of his forceful personality and an intuition for picking the right experiment, he was a revolutionary .
“There was a paradox in this combination of an elderly conservative gentleman of the “old school” and the proponent, nay the discoverer, of the latest word in this most modern field of knowledge: atomic and subatomic physics.
It was all part of the scene: Cambridge, the Cavendish and Rutherford alike; traditional forms and radical ideas; an enduring, time-beaten outer shell containing and protecting the vital, quickening activity within.”
Simplicity was the key to Rutherford, says Devons:
“There was an extraordinary transparent honesty and a deceptive simplicity about the clear distinction between fact and theory (opinion).
He was impatiently hostile to any attempt to obscure or to conceal or to complicate unnecessarily…it was the remarkable combination of a most powerful imagination counterbalanced by a sense of utter honesty that was most impressive and mystifying.”
“Rutherford’s emphasis on simplicity is proverbial: (“I’m a simple man myself…”). Simple ideas and simple apparatus, but powerful, conclusive results; simple, unpretentious appearances, but striking inferences: these were the Cavendish trademarks.”
Rutherford was a man of great energy and persistence, a keen golfer and motorist, and a mentor for young science students in Britain, especially New Zealanders.
James Chadwick, who won the Nobel Prize for Physics in 1935 for discovering the neutron (a particle first predicted to exist by Rutherford in 1920), was one of a number of scientists who studied under Rutherford and achieved lasting fame.
Another notable young colleague was Niels Bohr, who won his own Nobel Prize (for Physics in 1922) for placing the electrons in stable orbits around Rutherford’s nucleus and thus explaining the origin of light emitted by hydrogen atoms.
While at Manchester, Rutherford’s assistant was Hans Geiger, and the 1907 Rutherford-Geiger detector was improved in 1928 to become the Geiger-Muller tube we know today for measuring radiation.
Robert Oppenheimer, later to be known as the “father of the atomic bomb” for his leading role in developing the bomb in the Los Alamos Laboratory during the Second World War, also studied at Cavendish under Rutherford.
John Cockroft and Ernest Walton were driven by Rutherford to construct the first high energy accelerator and were the first to use it to split the nucleus by entirely artificial means.
Rutherford won a series of honours for his work, including the 1908 Nobel Prize for Chemistry, and 21 honorary degrees. He has featured on the stamps of New Zealand, Sweden, Russia and Canada.
In 1931, at the age of 59, he was named Baron Rutherford of Nelson, choosing as his coat of arms a design that included a kiwi and a Maori warrior.
He remained proud of his New Zealand origins and his family: on being awarded his baronetcy, he sent a telegram to his mother: “Now Lord Rutherford. More your honour than mine. Ernest.”
However the baronetcy was awarded at a sad time in his life: The Rutherford’s only daughter, Eileen had died eight days before, just nine days after the birth of her fourth child.
On visits Rutherford made back to New Zealand, he was a celebrated figure. He came home for the last time in 1925, for six weeks, to see family and give lectures.
In Auckland he stated, “I have always been very proud of the fact that I am a New Zealander.” Described by reporters as “an imposing figure, tall, well-built and with bright blue eyes”, Campbell chronicles how Rutherford was hailed as a national hero, lectured to packed halls and called for the Government to protect New Zealand’s natural heritage.
He also called for an institute to be set up in which New Zealand scientists could carry out research that would benefit farmers: this assisted in the establishment of the Department of Scientific and Industrial Research in 1926.
He was still a seemingly healthy, vigorous man, when in 1937, he entered hospital for a minor hernia operation after straining himself cutting down some trees.
Within a few hours of the operation it was clear his intestines were not working and they never worked again. Four days later, he suddenly said to his wife from his sickbed, “I want you to leave one hundred pounds to Nelson College.
You can see to it.” Then he added more loudly, “Remember, a hundred to Nelson College.” He hardly spoke after that according to his wife, and at the early age of sixty-six, Rutherford died, on 19th October, 1937.
His ashes were interred at Westminster Abbey near the tombs of Isaac Newton and Lord Kelvin. His medals were gifted to Canterbury College, now University of Canterbury. In 1992, his image was placed on the new New Zealand $100 note.
https://www.nzedge.com/legends/ernest-rutherford/
If you keep seeing the number 1 in your life, it’s a powerful sign that you need to remember that you stand at the very centre of your Universe, so believe in your sovereignty!
Your spiritual and angelic guides want to give you a big boost of confidence, so allow your heart to be filled with love and self-assurance! You’re on track!
“Number 1 reminds us that we create our own realities with our thoughts, beliefs, intentions and actions.
When noticing the Angel Number appearing take notice of the thoughts you had right at that moment as 1111 indicates that your thoughts and beliefs are aligned with your truths.
This number signifies that an energetic gateway has opened up for you and this will rapidly manifest your thoughts into reality.
The message is to choose your thoughts wisely, ensuring that they match your true desires.” – Sacred Scribes
https://www.miraclesarebrewing.com/11-things-to-know-about-1111/
https://numerologist.com/numerology/real-meaning-behind-angel-numbers-1-11-111-1111/
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