* * *
Despite Rutherford’s six-month absence, a steady flow of international students continued to find their way to the Cavendish, attracted by the laboratory’s global repute. Among them was an unknown and uncertain American physics undergraduate, J. Robert Oppenheimer, who would earn immortality and infamy as mastermind of the atomic bomb.
Given that Oppenheimer’s preference for theory contrasted with the Cavendish’s charter as essentially an experimental laboratory, it was never likely to prove a comfortable fit. But so keen was Oppenheimer to embed himself within the intellectual pivot of world physics that he wrote directly to Rutherford seeking approval to work at Cambridge. Rutherford’s lukewarm response, noting that entry to the Cavendish was restricted to those whose research capabilities were ‘far enough along to work on a problem of their own’,14 was pejorative, though not completely dismissive.
With Rutherford on his southern hemisphere sojourn, Oppenheimer fell under the supervision of J.J. Thomson, who decreed that the man who would later oversee history’s largest and most morally vexed scientific project must complete a basic course in laboratory training before being let loose on experimental apparatus. In return, Oppenheimer derided the lectures he attended at Cambridge as ‘vile’, and the practical instruction as ‘a terrible bore’.15
Oppenheimer would ponder theory deep into the night before returning to the daily practical routine he found so distasteful, and became so run down and disillusioned that one day, mid-conversation with laboratory colleague Robert Ditchburn, he collapsed and was only spared injury by Ditchburn’s reflexive save. ‘It has been suggested to me that since I prevented him from cracking his skull on the floor I am responsible for the atomic bomb,’ Ditchburn later mused.16
Months later, Oppenheimer was central to a more sinister episode when – struggling to cope in an environment where his theoretical brilliance was dulled by being but one of numerous science prodigies – he left an apple laced with traces of toxic chemicals on the desk of his tutor, Patrick Blackett. The poisoned fruit was left untouched, but Oppenheimer was placed on probation and instructed to undertake psychological counselling in London.17
History might also have taken a different turn had Rutherford been at the Cavendish to confront the erratic Oppenheimer. The professor with the occasionally incendiary temper bore no tolerance for petty academic squabbles, and would surely have taken a tougher stance.
Years earlier, upon joining the ceremonial line to enter Trinity College, where he routinely took Sunday-evening dinner, Rutherford overheard a curmudgeonly vice-master named Parry admonish a professor over some minor imperfection in the latter’s academic gown.
‘By thunder!’ Rutherford railed at Parry once all had assumed their seats at the elevated top table, slamming his palm onto the polished woodwork. ‘If you ever talk to me like that, I’ll knock you base over apex down those stairs.’18
However, at the time of Oppenheimer’s indiscretion, Rutherford and Mary were still enjoying their leisurely return from New Zealand, which included sightseeing stops in Ceylon (now Sri Lanka) and Egypt. When Rutherford did settle back into his office at the Cavendish, he was rarely in one place for very long. He threw himself immediately into further lecture tours across Britain and Europe, and between those engagements he reimmersed himself in the investigations that James Chadwick had continued making in his leader’s absence.
‘Chadwick and I are working at the scattering of alpha particles and hope to publish some interesting results before long,’ Rutherford wrote to one of his former colleagues at the start of summer 1926. ‘I want to know a little bit more about nuclei before I retire from actual work.’19
At that time, Rutherford remained oblivious to the impact that his Antipodean odyssey had exerted upon the young man who would soon become his trusted collaborator, avowed friend and anointed inheritor of his Cavendish legacy: Mark Oliphant.
7
‘A RARE QUALITY OF MIND’
South Australia, 1919 to 1927
When Oliphant began as a full-time university student in 1919, the year of Rutherford’s return to the Cavendish, he found himself among an influx of young men who had seen their lives disrupted, and often irrevocably changed, by four years of war. The only respect in which he stood out was that those who returned from active service had their fees covered by a grateful government, while boys like Oliphant deemed too young for the war effort had to pay their way.
Unlike so many of his later colleagues who had witnessed the First World War from hauntingly close proximity, Oliphant’s memories of that great conflict would be tinged by an adolescent’s sense of adventure. He had been preparing for his matriculation exams when the armistice was signed in 1918, and two of his uncles – Baron’s brothers Walter (Instructional Staff Lieutenant) and Douglas (Private, AIF 10th Battalion) – had served. Both had returned safely home, which meant the war stories that Mark grew up hearing carried an uncommonly happy ending.
‘It’s funny, my generation felt deprived of an experience when the war finished,’ he mused in his latter years. ‘We’d had our uncles and brothers in it and we missed out. I felt deprived because the war ended before I was eighteen and involved. I can remember an uncle coming home after being shot in the leg and he was a great hero to us boys, listening to the stories he had to tell.’1
On starting his university career, Oliphant’s initial vision was to utilise his science degree as a stepping stone to medicine, thereby satisfying the ‘do-gooder’ aspirations of his parents, who had accepted he would not be joining the Church. When he entered into further study, though, it became clear to him that the intensive theoretical focus of a medical degree held little appeal. As he knew from his schooldays, he preferred to be in the laboratory, ‘fooling about’ with hands-on experimental work.
‘A medical course is almost entirely learning by rote, and there’s nothing to think about in it,’ Oliphant would later rationalise. ‘You’ve just got to learn things, and I felt that this wasn’t for me.’2
Oliphant’s study choices were narrowing. He had been relieved of his position at the Adelaide Library because of his propensity to spend more time reading than re-shelving, and had paradoxically decided that medicine was not for him because it focused too heavily on reading. However, his skill with apparatus brought him to the attention of the University of Adelaide’s physiology professor, Dr Thorburn Brailsford Robertson, who seconded the teenager’s help for an experiment.
Robertson’s aim was to glean whether animals derived any sustenance from nitrogen present in air, or if they could survive being fed and watered in an environment bereft of the gas. Having established that the mice would not be hurt, Oliphant employed his talent for designing and manufacturing equipment to ensure the generations of rodents were raised and monitored within a controlled atmosphere consisting only of oxygen and inert argon.
While the experiment itself yielded little of scientific value, its revelation was Oliphant’s ingenuity in creating and maintaining a microclimate in which the mice were kept at a constant temperature, with a strictly scrutinised combination of the appropriate gases. It also required regular removal of all waste products. Echoing Rutherford’s formative years, the operating system for Oliphant’s benchtop kit was powered by a small electric motor, driven in turn by a water wheel.
‘The fun of building this equipment and finding ways of keeping the constituents constant, of removing the moisture that was produced, of introducing the food without introducing oxygen, of circulating the atmosphere and measuring it all the time by heat conduction to see what the relative proportions of oxygen and argon were, and automatically opening and closing valves, so fascinated me that I decided that physics was my milieu,’ Oliphant would recall.3
By the end of 1920, and doubtless due to Oliphant’s diligence, Professor Kerr Grant had offered the teenager a paid cadetship in the physics department. This required Oliphant to prepare and dismantle, clean and catalogue the apparatus u
sed each day for first-year practical classes.
Kerr Grant had earlier gained fleeting insight into his new departmental cadet’s character. Oliphant had once attended an Adelaide University Science Association meeting at which he had traded opposing views with the professor. The other students had looked on with a blend of disquiet and admiration as the pupil and his master firmly stood their ideological ground through a prolonged though entirely respectful debate. Later, Grant reputedly told a confidant, ‘You know, despite his erroneous ideas and his immaturity, I believe Oliphant has a rare quality of mind. It could take him a long way.’4
While the laboratory assistant’s role might outwardly have appeared to fall short of Mark Oliphant’s ambitions, he was delighted to take up the position. Not only was the cadet’s weekly salary of ten shillings equal to what he had been earning at the library, but the position came with a far greater benefit – namely, access to any course of his choice at the university, provided his duties in the physics laboratory were not compromised. The money he pocketed from his cadetship covered train fares to and from his family’s new home at Cottonville (now Westbourne Park), with the surplus handed directly to his mother for board.
He was regularly co-opted into what he described as ‘dog’s body’ jobs, yet he thrived on the practical and pragmatic stimulation of the laboratory, and his assuredness blossomed.
Now that experimental physics was his chosen discipline, it did not take Mark Oliphant long to embrace the field of research that would become his life’s work. Still, the intricacies inherent in some of its complex calculations would regularly elude him due to his limitations in mathematics.
Initially that shortcoming was masked by his competence in experimental work. In second-year physics he topped his class, but as the subject matter became increasingly impenetrable in third year, he found himself struggling. Oliphant always acknowledged his scholastic limitations, claiming he chose to invest effort in the subjects that most interested him, while being content to secure the barest pass mark in all others. And there was no doubting that his keenest interest lay in practical work.
Nevertheless, he successfully completed his Bachelor of Science at the end of 1921. He was then offered the opportunity to undertake an honours degree the following year, which he accepted, and benefited hugely from being one of only two students in the physics department being personally supervised by Professor Grant. Upon graduating with first-class honours in 1922, he continued his research work into surface tension, which had become his then area of expertise.
However, as he expanded his experimental skills, his curiosity was excited by the pre-eminent physics conundrum of the early 1920s: the properties of radioactive matter. Oliphant accessed a jar of uranium salts from one of the chemistry department’s supply cupboards, and joined the race to unlock the atom’s secrets through his own amateur attempt at transmutation. Employing an induction coil that generated around 100,000 volts of electricity and a vacuum tube into which he placed his sample of the radioactive element, he bombarded the uranium with electrons for hour upon hour.
Fascinated when the university’s chemistry professor, Edward Rennie, had explained that radium gradually decomposed to an isotope of lead, Oliphant aimed to initiate the same process in uranium by implanting additional electrons into its nuclear structure. That would – according to his narrow understanding of atomic theory – transform it into the isotope then known as ‘uranium x’ (later revealed to be uranium-234). However, the only noticeable change delivered by the lengthy experiment was to liquefy the overheated induction coil’s insulating wax.
Rather than dampen his enthusiasm, this unsuccessful foray into experimental autonomy bolstered Oliphant’s confidence. In the small university of barely 1000 students and a dozen professors, he continued to gain renown for the unusually quick and exceptionally skilful construction of apparatus he had exhibited since boyhood. He displayed a profound ability to craft experimental pieces, having learned the crucial art of glass-blowing from artisan Arthur Rogers who had originally travelled from England to work for William Henry Bragg, whose twenty-two-year tenure as Professor of Experimental Physics at Adelaide ended in 1908.
Rogers remained in Adelaide after Bragg’s return to Britain, and maintained a lifelong correspondence with Oliphant who had emerged as a first-class glass-blower under such expert tuition. This gift also helped ensure that Oliphant’s subsequent research career would be characterised by his reluctance to appreciate that others could not replicate the speed or intuition with which he built equipment.
And while ‘the young man with mouse-coloured hair sticking up from a very large head’5 – as one student contemporary described him – became wholeheartedly consumed by the world of academic possibilities, from the outset he was never motivated by personal reward or self-aggrandisement. His colleague and commuting companion Walter Schneider would reflect on this years later.
I think Oliphant always had the spirit of the true scientist. I greatly doubt if he ever possessed any materialistic ambitions beyond a sufficiency of food, clothing, shelter and some relaxation. He was totally at ease with himself.
His work was at the same time his reward, not something to be exchanged for dollars at piece rates, or by the hour. It was a free activity of his mind which he found fascinating, and sometimes dangerous, yet waiting to be done for its own sake – a drug for which most men have no taste. For him, and for a very few, it was . . . the meat and drink of life itself.6
* * *
Not that Mark Oliphant was oblivious to all activities beyond the laboratory. During his teenage years, he had met and become smitten with Rosa Wilbraham, a quiet, shy girl two years his junior. Neither could subsequently recall where they first met, but in later life, Mark would clearly remember the sight of Rosa’s hypnotic dark eyes and flawless alabaster skin, framed by luxuriant dark hair that would cascade below her shoulders if not drawn into a tight bun.
They began to see each other regularly at church social gatherings, and before long Mark was foregoing weekend reading and backyard woodwork projects to catch the train then walk to Glenelg South, where Rosa – by then, tragically, an only child – lived with her parents.
Rosa’s family quickly became fond of their daughter’s new beau; later, Rosa gleefully claimed that her mother ‘adored’ him. Mark would arrive at the large Pier Street bungalow of Frederick Wilbraham – a printers’ proof-reader who later worked as a correspondent for Adelaide’s principal daily newspaper The Advertiser – bearing a tennis racquet and picnic lunch, before the teenagers set out towards a nearby park for the afternoon.
The conversations they shared between sets of tennis and bundles of cheese sandwiches would have been vastly different from those Mark engaged in during the week, given that Rosa professed no science training, and did not take up paid work upon finishing secondary school. Yet they spent all their available free hours in each other’s company.
‘We had the loveliest of times together,’ Rosa would recall of their courtship, which included regular weekend outings such as formal dances and group picnics. ‘Mark was the most beautiful dancer.’7 On the spring day in October 1920 when Mark turned nineteen, they took the train and spent hours together in his beloved Adelaide Hills. Come Rosa’s twentieth birthday two years later, he proposed as they sat together on the trunk of a fallen tree.
They were married at St Peter’s Church in Glenelg on 23 May 1925. Rosa had celebrated her twenty-first birthday some months earlier; Mark was twenty-three. Using the smithing skills he had developed as a teenager, Mark crafted his wife’s delicate wedding band in the university laboratory, from the small gold nugget that his father Baron had unearthed from the Coolgardie fields. In sixty-two ensuing years of marriage, that ring left Rosa’s finger just once.
It was just three months later that Ernest Rutherford sailed into Adelaide and unknowingly recast the couple’s future. Mark Oliphant’s previously benign aspiration to pursue the life of a lecturer or exper
imenter was jettisoned virtually overnight, and his wife was swept along by his new-found ambition.
* * *
Yet the fire that Ernest Rutherford had ignited within Oliphant would ultimately smoulder and turn cold if he could not find a course of original study, and then a suitable means of getting to Cambridge. The solution to the first part of that problem became clearer at the start of the following year, when Professor Grant left Adelaide University to begin a twelve-month sabbatical at the laboratories of Thomas Edison’s General Electric Company in Schenectady, New York.
In Grant’s absence, Oliphant came under the guidance of the physics department’s acting head, Dr Roy Burdon, who – at the professor’s behest – had begun experimenting with the properties of surface tension, particularly in mercury. Burdon enlisted assistance from Oliphant, who had risen to the position of physics demonstrator and lecturer after completing his postgraduate research.
Even with his first-class honours degree, Oliphant remained unconvinced by his own academic acumen. ‘I think I was rather lucky to get this distinction,’ he conceded later in his life. ‘I’m quite sure now that I was nothing like as good as the students that I’ve taught in the many years that I’ve spent in university teaching since. But still, I did get this great uplift that came from earning something for myself and went on to a little research work in the spare time that I had from my duties as an assistant in the laboratory.’8
As part of that research work under Burdon’s guiding hand, Oliphant helped design and fashion apparatus for the mercury examinations, in which he would become closely involved. It also became his task to purify mercury samples, and he spent hours boiling and distilling the metal while its toxic vapour rolled down the stairs and seeped into the university’s basement workroom.
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