Before the cyclotron was functioning properly, John read an article about double beta decay that gave him an idea for an experiment of his own. Certain radioactive materials break up by giving off beta particles and the work described appeared to show that it was possible for disintegrating atoms to give off two beta particles-1- simultaneously. These particles are far too small to be seen themselves, but the tracks they leave through photographic emulsions can be seen after development as light lines on a black background tracing the path of the particle. Double beta decay-2- could be proven by finding two of the characteristic, thin, well-scattered tracks emanating from one point on a developed photographic plate. Perhaps, in between bits of his cyclotron work, John could finally prove or disprove the existence of the phenomenon.The method for the experiment was to put a sample of each material to be tested onto a photographic plate, shield it from all external radioactivity for several months, and then examine the developed photograph for tracks. John decided that if he could leave his samples somewhere deep under the ground, he could at least shield them from cosmic rays, which could confuse the issue by producing extra tracks on the photographic emulsion. At the same time he hoped to protect the plates from the radioactivity of the surrounding ground by burying them in a pyramid of lead bricks. He asked the manager of a local coal mine if he could 'store' some lead two thousand feet down. The manager said at first that such a store would disappear, but eventually found a small lockup area. To obtain a reasonable supply of old lead, John started to look at church roofs, but eventually found a government minister who was re-roofing his house, and bought the lead from his old roof from him.
Helped by a research student, Madeline (Madge) Walters, John recast the lead into bricks. For the next three weeks, the two of them made repeated trips on their bicycles to transport the lead to the mine. John checked standard photographic plates and found that the glass was itself slightly radioactive, which would create a few extra, confusing tracks to show up on the developed plates, so he bought some photographic emulsion from Ilfords, and, following the suppliers' instructions, poured it over perspex plates.
So the home-made plates bearing their samples were incarcerated in the subterranean pyramid for the required time before they were retrieved and examined for tracks. John and Madge were the first researchers not to get a positive result from their experiment, but flaws were eventually found in all the previous experiments that had shown the phenomenon. More than thirty years later, double beta decay was in fact shown to exist, but needed a far more rigorous experiment than was possible in the fifties. John's results had stated that double beta decay did not exist unless its half-life-3- was greater than 1017 years and the later experiments proved this to be a true statement, for the actual half-life was in fact considerably more than this.
John became increasingly busy. Work was continuing on the cyclotron, but new problems kept appearing. It was found that a 'booster' oscillator would be needed to encourage the main oscillator to start, which John and John Walker took a week or so to build, working straight through lunch breaks as they were so intent on getting the work done. Shortly afterwards the British Association for the Advancement of Science held its annual meeting in Birmingham. For a couple of months before the meeting started, John was closely involved in drafting a BBC Home Service radio programme on science that was to be broadcast at the time of the meeting, helping to choose the scientists who were to be invited to talk. During the meeting, John, who was the local secretary for physics, had to organise activities for British Association members for the afternoons. As soon as the morning lectures finished, members would come and ask to be put down for some visit or to change from one to another; and before they were finished, those who had gone to the first lunch were back with another set of queries.
John was rather proud of himself for being able to go without lunch when there was something to be done, but shortly afterwards he began to get internal pains like localised heartburn, which he suspected might be due to a gastric ulcer. He got himself referred to a specialist, who agreed that there was probably a small ulcer, but argued against an X-ray examination to confirm it, on the grounds that John would have to report it when applying for life insurance. He recommended that John should try dieting first, paying special attention to the regularity of his meals. From then on, John always kept some food in his office (at first biscuits and chocolate, but later boxes of individually wrapped processed cheeses) and always carried food with him together with a plentiful supply of antacids in case he could not get to a meal on time. In addition, Reinet learnt to provide meals timed to arrive on the table to the minute. These procedures did not cure the ulcer, but they kept its effects well under control. The ulcer remained a minor problem for the rest of John's working life, although it was rarely painful unless he was unable to take his usual precautions against it.
The delayed lunches were probably not the only cause of the ulcer. Ever since he had been at Cambridge, John had had occasional migraines. While he was at Ilminster another sufferer, Roger Hall, had told him that if he took nine aspirins at the first sign of visual disturbance, the following headache could be prevented. John had taken up this advice and found that it worked, but the aspirins could not have done his stomach any good. Stress was probably another contributory factor. John always crammed an enormous amount into the hours of every day and his nights were broken regularly by baby Jane who woke up and yelled every night for a year, and less regularly by calls from the night staff working on the cyclotron. John and Reinet took it in turns to get up to Jane in the night, but Reinet could not similarly help with the cyclotron. He also took world affairs very seriously, was deeply upset by the start of the Korean war in 1950, and continually worried about the expanding arsenals of nuclear weapons, trying to think of ways of getting people to see the problem as he did. Using a logical approach to every problem himself he always wished that world leaders would behave in a similar manner and base their decisions on facts; it was blindingly obvious to him that a nuclear war could not be won by anyone and that proliferation of nuclear weapons together with the escalation of their capabilities would not be stoppable once started. He was quite happy to suggest that unilateral disarmament would be safe for Britain, sure that a country without nuclear weapons would not automatically be bombed by others. Although John felt so strongly about all of these issues, he did not allow himself to rant or to sound peevish at his public lectures; rather he kept to an almost diffident tone while wearing his usual slightly embarrassed smile, explaining each step in his arguments carefully, and encouraging people to believe that they had come to his conclusions by themselves. Despite the rationality of his thinking, it is possible that all these worries took a toll on his health. For a lot of his working life, John woke very early, a classic sign of someone who is stressed or at least has too much to do. Typically, even this did not result in complaints that he was tired: once thoroughly awake, he would sit up in bed and read or get ahead with some written work.
In the autumn of 1950, Oliphant went back to Australia to become a research professor at Canberra. The cyclotron at Birmingham was not yet working properly when he left but not long afterwards, John was able to send him a telegram to say that they now had a beam of deuterons-4- . Deuterons were the first particles chosen to be accelerated by the cyclotron to emerge as a high energy beam, which would be applied to the required targets. Getting the cyclotron running did not reduce the workload on the people who had created it, as it still took a great deal of nursing. The staff took it in turns to do night shifts to look after it, and John came greatly to prefer the shift that started at three in the morning. He found that he could function well during the following day with no sleep after that time; after all, he often woke at that sort of time anyway. The earlier shift always left him feeling much more tired the next day. One night, John found that someone had written a poem into the control room book, and decided to do a little composition himself. He was very fond of Gilbert and Sullivan, and with apologies to them, wrote his own version of the nightmare song from Iolanthe. The nightmare part of his composition starts with this flight of rhyming physics:
For you're having a dream that the Prof has a scheme
to produce our own stock of Uranium
And he pooh-poohs your fears that it's bound to be years,
you're to make it with alphas on thorium.
You're to make half a ton, which he thinks will be fun,
if you work with a maximum current
Which you see through your tears will take 9 billion years,
though he doesn't think this a deterrent.
Then you find that's not all, there's a telephone call
for three thousand Curies of sodium
To be sent off tomorrow, with invoice to follow
and two or three pounds of polonium.
You yourself have a scheme for producing a beam
of deuterium still in its cylinders
Which are made to take flight by the pressure of light
from some twelve million searchlights on tenders
So you start it all off by requesting the Prof
for a grant of a few billion sterling.
But his well-expressed 'NO' takes the top half off 'Joe'-5-
and you have to be scraped off the ceiling.
Most of the rest of the song involved references to the more colourful characters to be found in the Physics Department. Over the next few years, some improvements were made to the song, and one year, John found someone to accompany him on the piano, and sang it at the Department's Christmas party. He judged this a success, and regularly wrote parodies for later events. When David was older he acted as accompanist and rehearsed John carefully before each event. John preferred David as the pianist, because he found it difficult to pick out the melody he was supposed to be following if there were too many complexities in the music and David understood the necessity to keep it simple.
Although John had a number of other ideas for improving his coal mine experiment, once the cyclotron had come on line everything in its environment became so radioactive as to make any work that involved looking for a few beta particles a month useless. While the cyclotron began to earn its keep turning out isotopes-6- to order, John started to use it to accelerate heavier ions than deuterium, first carbon and then nitrogen-7- , and went on to do some work based on the bombardment of various materials with a beam of nitrogen ions, which is described in the next chapter.
Professor Oliphant was not the only one to return to Australia. John Gooden became ill with Bright's disease, and although he was not told that he would not survive, he and his wife decided to leave England, and he died shortly afterwards. He and John had been writing a monograph called 'Cyclic Accelerators' that put together all the information the two of them had accumulated about cyclotrons, and also described John's development of an improved dee shape. John completed it on his own and it was duly published towards the end of 1950.
We children did not always see a great deal of John because he was so busy, but when he was available, he gave us his full attention. He had turned one end of one of the largest rooms in our house into a workshop and worked in the evenings to produce solidly built toys each Christmas. The dolls' house he built for me had a little trap door into a loft and its own electric light system featuring torch bulbs in each room. He also made a number of wooden jigsaw puzzles and, on some Sundays, he would offer to make a toy for one of us to order: once I had a doll that needed a bed and he made a nice wooden frame, painted it red, and added a firmly strung base. David loved talking with him and before he was eight was inspired with the wish to become a physicist when he grew up, and to discover centurium, the postulated name of the element of atomic number 100. (This element was found long before David could do anything about it, and is called Fermium.)
David turned nine in 1951, and John decided that he was old enough to try a walking and camping holiday. During the Whitsun holiday, John loaded all the necessary equipment into two rucksacks, making a very light one for David and a heavy one for himself, and they went to Ross-on-Wye to set out to walk to Monmouth down the Wye Valley. John paced their trip carefully aiming to cover no more than eight miles a day and allowing for plenty of breaks to avoid tiring David. David used the breaks for a change rather than a rest, getting to the top of anything climbable he could find and, according to John, a good deal that wasn't. They stopped at farms for milk and eggs and in villages for other provisions, which they cooked on a primus stove. They pitched their tent anywhere convenient: one night they found a good spot inside Goodrich Castle up against the solar wall, breaking camp early the next morning so as to be off before the custodian caught them. Their last night was spent inside a large stone box that had previously been used for storing salmon nets. While they sat up in their sleeping bags eating their supper, John told David that if the box collapsed on them, future archaeologists could assign them to the aluminium age on the basis of the pots and pans buried with them! I don't know how much sleep David got that night!
A fortnight each summer was spent on a family beach holiday, usually in Wales. As most of Birmingham went on holiday, by train, at the same time, some of the journeys to the seaside were slow and involved very crowded trains. Sitting on a beach for long periods watching children play did not particularly appeal to John, so he spent some time looking for rock pools and photographing anything interesting he could find. This did not mean that he detached himself entirely from the family: he would throw himself into the engineering of sandcastles against the tide and took over all the washing of Jane's nappies while this was still necessary. (He applied his knowledge of the theory of solution chemistry to this task to devise his own rinsing regime that ensured that all the nappies were equally free of soap with a minimum of water and effort.)
Heaver's health was now deteriorating. Worried about whether he was looking after himself properly, John and Reinet brought him to Birmingham to live with them. This turned out to be a disastrous experiment as Heaver could not cope with learning his way around, became confused about the time of day and could not recognise who was who. Eventually it was decided to return him to Heavers with a living in housekeeper to look after him, but he had by that time forgotten his way around there. He died of pneumonia in 1952 with Celia at his side.
Shortly before Heaver's death, it was time for me to start school. Like many other socialists who had fought for free education, now that it had arrived, John and Reinet could not accept that the classes of over forty in most primary schools could possibly provide a reasonable start to an education. They found a place in a local private school for me, and booked a place in the same school for Jane.
After Professor Oliphant had left England, a successor was required. The obvious choice seemed to be Cecil Powell, one of the leaders of the movement to increase the social responsibility of scientists, who had won the Nobel prize for physics in 1950, and was currently a Professor at Bristol University. He was appointed even after he had presented a long list of requirements, including the need for a large number of workers to be employed who were to trace tracks down microscopes to further the work on nuclear emulsions. Then it was discovered that he was a communist. The decision that followed this discovery, to renege on his appointment, was not unanimous, and caused a lot of acrimony in the Physics Department. Professor Peierls was so upset by the idea of the impression Professor Powell must have received from his late rejection, that he went down to Bristol himself to explain that not everyone had agreed with it.
The second choice for the post had been Philip Moon who, apart from a period in Los Alamos working on the Manhattan project during the war, had been at Birmingham University since 1938, becoming a professor in 1946. Following his initial rejection he had already set off for Canada for an interview for a job there, but he was brought back to England and made the Poynting Professor of Physics. This started a difficult time for John. Although Professor Moon had been working on nuclear physics at Birmingham University for longer than he had, John saw him as taking little interest in the cyclotron because he spent a lot of time working on a very high speed rotor to be used in the investigation of resonant gamma ray scattering. John also felt that he lacked Professor Oliphant's broad interests and ability to think laterally and did not build other points of contact with members of his staff. However, I don't believe that this was a general view in the Physics Department and others saw Moon as a kindly, unaffected person. Work on the synchrotron was stopped at about this time, but this was in fact the only course of action that could be taken, as it had already been overtaken by bigger and better machines in America where a good deal more money was available, and Moon could not be blamed for this decision. Sadly, though, the relationship between John and Moon started off on the wrong foot and John often reacted to his new professor's decisions as if he had been treated unjustly. It is quite possible that the Professor had reservations about John too: when busy, John tended to let administrative tasks slide, seeing them as less important than practical physics work and as he was busy all the time, there were always piles of untended paperwork in his office.
In August 1952 John was invited to join a cultural party visiting China. He had been reading about developments in China for some years and was thrilled by the idea that he could go to see genuine communism emerging as a viable system of government. He was already aware that the Chinese had not been relieved of rigid rule, but thought that the new regime was truly improving living conditions for the poor: although not a practising communist himself, he still believed passionately that communism should be an excellent way of running a country.
There was only a short time to get ready, as the invitation came less than two weeks before the departure date. The party was due to return the day after the University's term was to start, and, having found someone willing to stand in for his lectures that day, John went to check with Professor Moon that this was in order. Professor Moon told John that if he was not back on the first day of term, he would consider that he did not want the job, and would expect his resignation; it was not long since Cecil Powell had been refused a job on the grounds of his communism, and Moon may well have felt that he could not condone the use of University time for visiting a communist country. John had no choice but to arrange to return early. When telling me about this event, John used the phrase 'told me stiffly' to describe his professor's manner, which makes me wonder if it wasn't entirely Moon's own opinion that John should come back on time or resign.
The journey took some days, including a two-day stop in Moscow. While they were there, John escaped from the party who were going to be given a four hour trip round a picture gallery, and set off to visit the planetarium equipped only with a card on which the party's interpreter had written the Russian for planetarium, together with some kopeks. John went to the nearest bus stop, showed his card to the conductress and looked questioning. She beckoned him aboard, picked what she wanted from his handful of kopeks and gave him a ticket. After two or three stops, she put him off the bus, having written another bus number on his card and pointed to where he should wait. The next bus conductress pointed to the planetarium with nods and smiles when they arrived, and he bought an entrance ticket without trouble but the girl on the auditorium wouldn't let him in. So he went back to the ticket seller, who eventually managed to indicate that the number on the ticket was not a seat number, but a date - that of the following day!
A certain amount of sight seeing could also be done from the various aeroplanes they were in over the next few days. Flying over Lake Baikal, the windows started to fog up as they were flying quite high, and John showed off his technical know-how when he went down the plane rubbing the windows with a little spit and some soap flakes that Reinet had packed for him, which kept them clear. When they were due to fly over the Great Wall of China, John interrogated his Russian dictionary for the words for fly - low - over - Great - Wall, wrote them down and passed them to the pilot who nodded several times with much emphasis. However, they crossed the Great Wall flying higher than usual, and John decided that his note had been interpreted as a query as to whether they would be flying over it.
The party was settled in a large modern hotel near the centre of Peking (as Beijing was known by English speakers at that time) for the first part of their stay. They were given two interpreters and asked to write down what they would like to see. John's request to see a big hydroelectric scheme had to be abandoned when he discovered that the journey to see one would take nearly the entire stay, but all other requests seemed to be granted - even a tentative request by several of the party to see a political prison.
For each trip, the participants were picked up in a large American car whose blaring horn seemed to attract large crowds of enthusiastic onlookers wherever they went. John took this as support for his belief that the Chinese people were better off than they had been under the old regime. Without speaking the language it was of course difficult to find out anything that they were not intended to know, but John felt that if the Chinese were being controlled through fear, noisy government cars would have been peered at from behind curtains by a sullen populace.
John had asked to see University science departments, especially those connected with nuclear physics, and after visiting a laboratory was usually taken back to the home of one of the scientists he had met. Most of these scientists spoke English, and from them, John gained the impression that they were more than happy with the way the country was now being run. One professor of physics told John that he could now afford to have a bicycle of his own, and that his family ate meat and vegetables every day.
One day they went to see a village a few miles from Peking. The houses they saw consisted of single rooms for ten to fifteen people with one to three raised brick beds under which a fire was kept going in the winter and on which the whole family slept. Practically the whole village turned out to see them, but there were two or three men left hoeing in a nearby field. On enquiry the visitors found that these were ex-landlords who had been 'liquidated' by being degraded to poor peasant status and had not been allowed to stop work for the visit. The villagers gave them lunch with a mild beer-like drink and another much stronger one, which, it appeared the visitors were expected to drink at a single draught. John, who rarely drank any alcohol at all, knew that it was too strong for him to do that, so he got the interpreter to explain to the villagers that it was better and stronger than any he had been able to get in England and that he could appreciate it better if he drank a little at a time.
John was much impressed by the discovery that the housefly had been hunted almost out of existence in the whole of China. A small bounty had been offered for dead flies, which had resulted in children discovering ways of catching them so that they could hand parcels of them in to the authorities for a little pocket money.
For a souvenir, John was very keen on obtaining a Mah Jong set, but could not find one at any of the shops he visited. He asked his interpreter why a set was so difficult to find, and was told that the game had a very bad name, because it was always played for money and frequently led to catastrophe when a family provider ran himself into irretrievable debt and killed himself. So John explained that he wanted a set so that he could play the game with his children when on holiday. The next day the interpreter told him that it had been arranged that the local multiple store would have two or three sets to show him. John paid a hundred thousand Chinese dollars, perhaps thirty pounds, for the one he preferred, a second-hand but opulent set.
Each evening while they were in Peking, the party was entertained at a large formal dinner by a different group or society, such as eminent lawyers or doctors. At one of these dinners the visitors were welcomed by eleven little girls each with a bunch of flowers for one of them. He wrote to Reinet:
"The happy excitement of the little girls - about 10 years old - was so great that I nearly made my lip bleed in avoiding crying."John loved trying all the new foods. His ulcer was giving him very little trouble: Reinet had given him some home made biscuits to carry with him in case there were long gaps between meals, but this never occurred: when they arrived anywhere, they were given tea and some food; when they arrived back from anywhere, the same thing happened.
After some time in Peking, the party left by train for Canton. Each member was given his own sleeping compartment, and all the travelling was done during the night. Every morning they got up to breakfast at a new place and were shown round all day. After they had had dinner with the local Arts and Sciences Circle they would rejoin their train for another night's travelling. Once in Canton, they visited various scientific establishments. John took advantage of an article on chemistry he found, which was written in both English and Chinese, to compare reading speeds as it had occurred to him that, although it must take longer to learn to read and write Chinese, it might be quicker to read having fewer characters per word to look at. He got a Chinese chemist to read the Chinese while he read the English version and found that they both finished at the same time. His letters to Reinet made it clear how much he was enjoying every single day. Towards the end of the holiday he wrote:
"All my love my sweetheart. I miss you terribly at times, but in the day am usually too busy and interested to remember your existence."John and one of the other members, Bill Pirie, who also had to leave early, took a train across the border to Hong Kong. There John looked up his old school and university friend, Wallis Chapman, who was representing his firm in Hong Kong and stayed with him while Bill stayed in a hotel. Bill and John decided that they ought to go and see the British Consul in Hong Kong to give him some up-to-date information on China. He welcomed them, and they told him of the near universal vaccination, the abolition of flies and that liquidation of landlords didn't always mean their execution. To their surprise he knew all of these things, so they asked why the West still believed the worst. "The trouble is," he said, "that the Americans believe their own damned lies."-8- At last they flew home via Calcutta, bringing John home just in time for the beginning of the new term, allowing him only a few hours to recover from a migraine, presumably the result of the accumulated tiredness of the trip together with the crossing of several time zones on the way home.