The nature, culture and living in a small village in Japan just after the last world war, reflected through the boy’s eyes.

 

Chapter 9 　Science-2　Coping with the boredom of everyday life

Yoshiharu Otsuki (Sendai, Japan) and Yasufumi Otsuki (London)

 

1. Nuclear Power

At the end of August, after the long summer holidays, the second term of his first year in high school started. (The school had a three-term system.)

‘Hello everybody. I’m sure you all studied hard, and it looks like some of you also played a lot during the long summer holidays,’ the class teacher said from the stage, looking directly at the boy. He understood the teacher’s sarcasm immediately – he was the only person with a sun-tanned face who didn’t belong to a sports club.

In order to be a nuclear power scientist, he reasoned that he would need to study in one of the seven universities that had been imperial universities before the war. One of them is located in the main city of the region he lived. His prefecture had a school district system, and students had to go to the high school that was in the same district as the middle school. Naturally, there was a big difference in academic ability between students in the main city and students in the rural districts. In the high school in his district, only a few students went to university after graduation, and only one student in several years went to the imperial university in the area. Since he already knew himself to be lazy and likely to be come even lazier in his unstimulating environment, he thought he would never be able to pass the entrance exam for that university if he stayed in his present school.

This was not a conclusion he’d reached by himself – more than five students of his age had already left the local school to move to a middle school in the city. As there had to be a legitimate reason for changing schools, and seeing as his father was already living in the city, he pleaded with his mother to let him move there and live with his father. Fortunately, she agreed to let him, and in the spring of his third year, he transferred to the city school. Schools in each district used different textbooks, so it was said that transferring schools in the third year was too late for students aiming to go to high school. Happily, he succeeded in passing the entrance exam for a school with one of the best academic records in the prefecture. It was the first step towards becoming a nuclear scientist. He realized that his score hadn’t been high and he’d in fact only just scraped through, but he was quietly satisfied that his marks in the first prefectural proficiency test, held before the summer holidays, ranked him in the middle position among four hundred students. Even so, his mother scolded him, saying that she had almost fainted with shame when she saw his results. He thought she was too demanding but she was right – he would have to be in the top 10% of students if he wanted to study nuclear power at the faculty of engineering of the university he was aiming for.

He was used to her constant scolding and was able to ignore it completely, and had a fantastic time in the summer holidays. Every day in the holiday, he had breakfast with his father and then went to school, spending the whole day reading books under a tree and swimming in the school pool. (There were no lessons but the school was open during the holidays.) In the evenings, he made an effort to stay up late and study but more often than not, he fell into a deep sleep.

Of course, as the teacher had noticed, he became as brown as students in the swimming club, who swam outside every day. Only one thing spoiled the happiness of that time. Studying nuclear power in school gave him a better understanding of the subject. He had thought that electricity was generated directly from nuclear fission, so he was disappointed to discover that steam generated by heat rotated a turbine, and the rotors generated the power – not so different to the process in conventional thermal power generation. Being influenced by the spreading prejudice in his village at that time towards charcoal makers, who were treated as a class lower than farmers, it was disappointing to think that nuclear power was only a substitute for coal and charcoal.

Furthermore, after he came to know that the biggest problem with nuclear power was disposing of the spent nuclear fuel, he lost his passion for it. Consequently, even before the end of that golden time in the summer, he had let go of the dream that he’d had since the exhibition. Having lost something to aim for in life, his marks dropped to leave him bottom but one in his class by the end of the third semester of the first year. As I’m sure you can imagine, his family were far from pleased.

 

2. The number of diagonal lines in polygons

It was a lesson about mathematical induction in the second year of high school. The students were taking it in turns to write answers for the questions in their textbook on the blackboard. The students were taking their turn based on the order of the position of their desk, and the boy had worked out that he would be called upon to answer a question about how to obtain the number of diagonal lines in polygons by using induction. Then suddenly he felt himself in a quandary. He had, of course, prepared for the lesson, and he already knew the answer. However, he really wanted his teacher to look at a different answer – the solution that he had found himself, even if that alternative answer had originally been discovered two thousand years ago.- Even now, it is still usual in Japanese education that solutions to problems in textbooks other than those used by the teacher are not accepted to be correct. On the way to the blackboard from his desk, he still couldn’t make up his mind whether to write his own solution or the one in his textbook. At the last moment, he decided to write his own answer, but was already regretting it by the time he got back to his desk. He even thought about going back to the blackboard and rewriting the answer, but the thought of the other students’ eyes on him as he did so seemed worse than getting a bad mark from the teacher. The teacher started to check the answers written on the board. The boy’s heart was beating strongly, and nearly burst out of his chest when the teacher started to examine his solution.

‘Well, I understand this answer. It’s different to the one in the textbook but this one is also right,’ the teacher commented in his usual calm and assured voice. The boy couldn’t prevent a smile appearing on his face, and that teacher became the only person he ever trusted or respected.

<Proving the number of diagonal lines in polygon by induction method>

　The number of diagonal lines in polygon is expressed by S=n(n-3)/2 eq.1

1. at n=3, S=3(3-3)/2=0 So, eq.1 is true
2. at n=k, eq.1 is assumed to be true, so eq.1 is explained as S(k)=k(k-3)/2.
3. at n=(k+1), the number of diagonal lines increases as 1+(k-2)=(k-1),

so k(k-3)/2+k-1=(k(k-3)+2(k-1))/2=(k2-k-2)/2=(k+1)(k-2)/2=(k+1)(k+1)/2.

This equation shows that eq.1 is true for n=k+1.

Then from 1)~3), it is proved that eq.1 is true for all natural numbers.

The End

 

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The Japanese Rustic Life in 1950s . ９

The nature, culture and living in a small village in Japan just after the last world war, reflected through the boy’s eyes.

Chapter 9　SCIENCE-2　

　　Coping with the boredom of everyday life

Yoshiharu Otsuki (Sendai, Japan) and Yasufumi Otsuki (London)

 

１．Button toy (‘Boon Boon top’ ) (1953)

It was a chilly night in early winter. The boy’s family – the boy, his mother and elder sister – were in the habit of listening to radio programs every Wednesday night while warming themselves sitting around a ‘Kotatsu’⁽¹⁾ heater positioned in the center of the living room. Tonight, however, he was busily doing something in front of the ladder hanging from the attic into the living room. The family sat beside him listening to the radio program, sometimes casting disapproving looks in the boy’s direction.

　　　　　　　　・・・・

-(1) A Kotatsu is a traditional heater that has been used in Japan since the 14^th century. It consists of a square or rectangular table top, a wooden frame containing a heating source, and a thick quilt. It’s 3~4ft by 3~6ft, depending on the family size, and about 1.5ft in height. The thick quilt is draped over the frame in order to trap the heat, and the tabletop is placed on top of it. Sitting around the Kotatsu placed on the floor with the quilt over their legs, family members dine, chat, read and engage in all the other usual family activities. Burning charcoal in a ceramic container was used as the heat source down to the late 1950’s. Since then, an electric heater has come to be widely used. This new type of heater is healthier and safer than the old one, not only because of the high fire risk but also because burning charcoal produces carbon monoxide, which can lead to suffocation. A Kotatsu doesn’t warm the room itself, so a separate ceramic pot, ‘Hibachi’, containing burning charcoal was used for that purpose. (Nowadays, air conditioners and oil heaters are used instead.) –

・・・・

His mother muttered to herself, ‘Once that boy starts to do something, nothing distracts him.’ The elder sister responded to her disinterestedly, ’What is obsessing him today?’

After a while, a strange sound coming from where he was sitting made them give one another a look. His mother asked him, ’ Last time, you made that awful stink, and then before that there was that big hole you dug in the ground, and we’ll never forget that night you spent in a persimmon tree – What on earth are you up to this time?’ Without replying to her question he continued to concentrate on swinging his upper body rhythmically back and forth. The sound, ‘Boon, Boon’, like an amplified buzzing of an insect’s wings, was heard while he synchronized the swinging of his body. A naked lightbulb projected his shadow onto a wall, growing bigger or shrinking, as if it was the silhouette of a monster. Usually, at least one of his family was amused at his actions, but this time they seemed not to have any interest at all. Maybe they were very tired after working all day or perhaps they were absorbed in the radio program. The first radio program was finishing, and his mother seemed to be about to stand up to take a look at what he was doing, but then sat down to listen to the radio again. ‘Boom, Boom’, the sound echoed around the room for a while and then ceased. He was obviously completely absorbed in something, but everybody else had already lost interest in him. After a while, the sound, ‘Boon, Boon’ began echoing around the room again, and this time even louder than before. A troubled look came over their faces as they tried to ignore the sound and concentrate on the program. But they were used to the disturbances he caused, and they continued to listen to the radio without saying anything to him. The ‘Boon, boon’ sound continued for a short time, and then ceased again.

The radio program on the air that night featured ‘Manzai’ (a kind of stand-up comedy that usually involves two, sometimes three people.), ‘Shamisen Mandan’ (comic chat and shamisen playing performed by one person – shamisen is a traditional Japanese stringed instrument, a bit like a banjo.), ‘Rokyoku’ (narrative singing by one person, generally accompanied by shamisen), ‘Kodan’(historical stories told by one person) and ‘Rakugo’(a talk by one person for the purpose of causing amusement, involving parody of famous stories or short comedy sketches etc.).

The mother casually looked over at her son during an interval between the Kodan and Rakugo. He appeared to be making something with a piece of thread about 0.4 inches in diameter. As soon as the next program started, however, she forgot all about him and went back to listening to the program, now a Rakugo performance, with his sister. Suddenly, an even louder ‘Boon, Boon’ sound echoed through the room, surprising his mother and sister. The mother cried out twice, as is the usual Japanese habit when someone wants to express admiration or surprise etc., ‘ What’s that? What’s that?’

‘Boon, Boon, Boon.’

As he got his upper body to swing faster, the sound got louder and it became impossible to listen to the radio.

‘For heaven’s sake! Stop it!’ his mother shouted over the Boon, Boon sound. He wanted to continue but he was now aware that if he didn’t obey his mother, she might get really angry and not make him a lunch box to take to school the next day. He reluctantly stopped and joined them listening to the radio. It was a Rakugo performance. Rakugo can be divided into two kinds. One is classical Rakugo, which are well-known stories that have been performed for many years. The audience enjoys minor changes made to the story by the performer, or just the way that a particular performer tells the story. The other type is contemporary Rakugo, which usually consists of several short stories which are just vehicles for jokes. They are often slapstick comedies based on the performer’s experiences. Influenced by their mother’s taste, the family preferred classical Rakugo.

This program being contemporary Rakugo, the boy soon lost interest and started looking back on the events of the day.

After school he had gone to the house of a boy whose family were farmers. Early winter was the time when, harvesting being completed, a farmer could rest after the non-stop work of the year. In the mild sunshine, children were playing a game with a nail – ‘kugisashi’. A housewife watched them playing while she ate pickles with her baby on her knee. ‘Kugisashi’ is a game of territory acquisition played by several people with a nail of 5 or 6 inches in length. Each player decides his starting point, and then they take it in turns to throw the nail. When someone succeeds in getting the nail to stick in the ground, they can draw a line between the nail and their starting point. After several turns and when you can enclose an area with lines, you get this space as your territory. This continues until the space has run out, and then the one with the most space is the winner. This game used to be played all over Japan but has completely superseded by computer games.

After playing the game several times, they got tired of it and sat eating cookies around the mother and her baby. She took out a button and a length of thread from a sewing box, and then threaded the thread through the holes of the button to make a loop. The middle fingers of both hands were put inside the loop, with the button set in the center. Both hands were held in front of the chest and expanded to pull the loop taut as shown in following figure.

 

 

Then she expanded and shrank the space between her hands repeatedly, thus stretching and loosening the loop. At first the button just jumped slightly but as this action was repeated, the button began to spin.

 

 

The thead made a soft ‘Boon, Boon’ sound. The children gazed at the movement of the loop and the spinning of the button. This game was called ‘Boon, Boon Top’. Decreasing the space between the hands seemed to make the loop and button dance, but if the space became too small, the circular movement broke up and the button stopped spinning. Using another technique, she rotated the loop around the button, this time instantly creating the ‘Boon, Boon’ sound. She took the baby’s hand and they did it together. The baby cooed with delight.

The children scrambled for thread and buttons in the sewing box, and got to work on making a ‘Boon, Boon Top’. The boy also set to work but was clumsy by nature and so was unable to thread the thread through the buttonholes. He grew impatient as the other children managed to do it more quickly than him. Eventually he made a loop and started to try and play the game. He experimented moving his hands at various speeds but without success. He suddenly remembered the other technique that the mother had used and tried to imitate it. After several tries, he was able to expand and contract the thread and the button started spinning smoothly. A smile appeared on his face as he felt the pleasant sensation of the vibration transmitting through the thread in his hand. Each child was engrossed in making the sound. Altering the space between his hands and changing the speed, he stared at the trajectory of the button and thread. Then abruptly the thread snapped. He set things up again with a new piece of thread and started again. Two things fascinated him: One was that the loop of thread seemed to be behaving like rubber, even though the thread itself only stretched slightly when it was pulled. The other was that even fine thread can make a big sound. After playing for a while, he noticed that the skin on his middle fingers had peeled so much that there was bleeding. He’d been so absorbed in the game that he hadn’t felt any pain.

Even after he got back home from his friend’s house, he was still fascinated by the ‘Boon, Boon Top’. In the beginning, he was interested in the reason why the thread of the loop appeared to be like rubber, even though the thread itself didn’t have an elastic quality. So he set about trying to find the reason for it. He found that only using one piece of thread with the button in the center (figure 2) did not produce the same movement. Using the thread loop without a button didn’t seem to work either. Then he examined the end of the broken thread using a magnifying glass, and found that the fibers inside seemed to be untied. Then it dawned on him that the twisting of the thread was a key part in producing the movement of the toy. He wondered what would happen if he tried a thread without that twisting, like a piece of fishing line. Sure enough, it didn’t work, so he had found one important requirement for making the ‘Boon, Boon Top’.

The next point of study was the button. He tested different buttons of various sizes but they didn’t seem to make a difference to the movement of the loop. The heavier the button, the stronger the power needed to produce the movement, but the thread broke in a shorter time. If he had known the classic theories of dynamics, he would have realized that his experimental results indicated that the toy was exhibiting the following physical phenomena:

1. Expanding the loop slightly causes tensile strain in the thread, which due to the twisted structure of the fibers in the thread results in rotating stress.
2. The rotation stress in the thread makes the button rotate.
3. When the hands are relaxed, the rotation of the button is maintained, according to the conservation law of inertial power, and shrinks the loop by the entwining of the fibers in the thread.
4. Synchronizing the movement of the hands and the button rotation results in steady expansion and contraction of the loop.

Of course, he did not know anything about physics, so he did not understand the physical processes of the toy. Then another thought came to him: If the twisting of the thread was really the root cause of the Boon, Boon sound, did the difference of thickness of the thread pair consisting the roop affect to the movement? He made scuh toys and tried to move. It was a little difficult to start and also keep moving. 　

While playing around with these experiments, another question occurred to him: Was using the button an indispensable condition? That is, from the physics point of view, was it necessary for the object (causing inertia?) to be round? He tried it with buttons of different shapes and was successful each time. The boy was nothing if not persistent, and he even went so far as to see whether it was possible to make a Boon, Boon top using a propeller made for a paper plane. He found a piece of bamboo in the barn and cut it into small strips of different sizes with a knife and saw. He’d just finished making two holes in the center and shaving it into a propeller shape when his sister saw him.

‘What are you up to?’

He was startled by the sudden sound of her voice – ‘Ah, Chikochan,’ (The nickname of his sister) he replied in a slightly husky voice, being thirsty after his exertions.

‘What are you doing in such a dim light? You’ll hurt your eyes,’ she said in an unusually concerned way.

‘She must have had a good day at school – maybe she got full marks in a test,” he thought to himself.

He ignored her and carried on making the toy, first trying with a short propeller.

He made a loop by threading the thread through the holes and tried to get the toy going, but it was more difficult to rotate the propeller than the button. He tried again and again and gradually got the knack of it and the propeller started to spin.

‘Ahh!’ he cried out, the thread snapping suddenly. He changed the thread for a heavier one and got the propeller moving again. This time the propeller produced a softer vibrating sound than the button had. He started wondering what would happen if he positioned the holes in the propeller off center. Most children could probably guess what would happen but he wasn’t satisfied until he’d actually tried it. He found that both the rotation of the propeller and the vibration of the thread became unstable, making it difficult to keep the movement steady.

When he got to that point in his recollections of the day’s events, the radio program finished and he got back to making the toy. He tried propellers of different specifications in subsequent tests. Unfortunately, he wasn’t smart enough to come up with anything other than the most basic of variations to such things as length and the inclination angle of the cross section of propellar.

He started again right away, this time using a new version with a big propeller. The propeller rotated vigorously with a louder sound. With one end fixed to the rung of the ladder going up to the attic, he manipulated the other end of the loop using both hands, now while wearing gloves to protect his fingers. It was easy to see that increasing the angle of inclination changed the sound. Already covered in sweat, he made another attempt with the biggest propeller of the day. ‘Boon, Boon, Boon’ – it made a terrific noise, causing the ladder to shake and dust to fall from the ceiling.

‘Hey, what on earth are you doing? Everywhere is getting covered with dust – Stop it!’ his mother shouted, putting an end to his exciting experiment for that day. His mother’s angry utterances always brought things to an end, like the punch line in a Rakugo story.

If he were to have gotten any further with his experiments, he would have needed to know about the theories of elasticity on torsion and air dynamics on propeller rotation. However, he had no such knowledge so he just enjoyed playing with the toy. Tired after his eventful day, the sweat-soaked boy got under his cold cotton futon (traditional Japanese bedding) and fell into a deep sleep, satisfied with the day’s experiments.

2. Set Square (1955)

One of his treasures was a set square made from a thick sheet of plastic. He forgot who gave it to him. Did he use it to study mathematics? Of course not! He just sucked it because he liked the taste of the plastic. That day, his primary school was closed, though both the middle school his mother worked at and the high school his sister went to were open as usual. All his friends were busy helping out with farm-work, and it was too cold to go fishing. He just sat idly at the kotatsu, lonely and bored. He couldn’t be bothered to read a book – he’d already looked through all his sister’s textbooks that had pictures. He just sat there sucking the set square, a small pool of dribble forming on the back of the calendar covering the top of the kotatsu.

While stirring the saliva island with the set square, another idea started to come to him. After wiping the corner he’d been sucking, he used the set square to draw a straight line on a piece of paper with a pencil. Then he added two other lines and made a triangle. After staring at it for a while, he drew a square as well. Then he made the lines thicker by drawing over them repeatedly, and then aimlessly drew diagonal lines with a red pencil. His interest now piqued, he drew a pentagon and added diagonal lines connecting the angles with the red pencil. There were four red lines. Next he drew a hexagon and added nine red diagonal lines, followed by a heptagon and an octagon, with fourteen and twenty diagonal lines, respectively. The first figures he drew were small and it was difficult to count the lines, so he drew them bigger and connected them again. He didn’t get beyond the octagon. He wondered if there was some correlation between the number of angles and the diagonal lines of the polygons, and wrote down the numbers.

Triangle – 0, square – 2, pentagon – 4, hexagon – 9, heptagon – 14,

octagon – 20.

He started to think about a mathematical formula. Since a triangle did not have any diagonal lines, he reasoned that any equation of diagonal lines and the number of angles should contain “-3”. Now, he became completely absorbed in trying to find some common element between them. Finally, he was able to come up with the equation as number of diagonal lines = n (n-3)/2 (n: number of angles). Playing around with the paper and pencil had been more fun than finding the mathematical formula, but he felt satisfied.

3. Nuclear Power Generation (1956)

In mid-October, an exhibition about the peaceful use of nuclear energy was held in the main city of the region where the boy lived. This city, where his father lived apart from his family, was about two and a half hours away by bus and train, so the boy only visited the city about once a year.

Unexpectedly, his mother declared that she would take him to the exhibition. Her reason for doing so was probably somewhat selfish. Maybe she felt a bit guilty because, although she was a teacher, she often left him alone to care for himself, no doubt because she was tired after teaching other children all day at school. Or, more likely, it was for the following reason.

At that time, children of primary and middle schools were given reports 3 times a year, and the highest achievers were commended. Of course, being a teacher, children who got this award were his mother’s favorites. Accordingly, she told her son to study hard every day, but never had the time to make sure he did so. The boy always intended to obey his mother but somehow was always too busy playing to open his textbooks at home. Consequently, whenever he showed his report card to his mother, she complained, “ Why is it that all my colleagues’ children get good marks but your grades are always so poor?” Well, there were not uniformly poor. For example, for PE, drawing, craft and mathematics, he usually got a grade 2 or 3. (5 being the highest) In other subjects, he usually achieved a 3 or 4 grade, and, for some reason, he regularly got full marks in social studies and Japanese. However, his teachers’ comments always lamented his disobedience and inability to apply himself to anything for very long. I’m sure many mothers have similar stories of feeling shame upon reading their children’s reports and, of course, the boy never got an award.

Despite not taking a more active approach in trying to get her son to study, his mother still must have worried about him. She often said things like, ‘ Your sister got full marks again – Why can’t you be more like her?’ His sense of shame prevented him from being able to look his mother in the eye when she scolded him, and he started to develop an inferiority complex. (If she had been a true “educator”, she would have encouraged him by telling him that his sister’s achievements evidenced his own ability, and she would have tried to find out the real cause of his lower marks!)

And so, she might have reasoned that if he found something new and stimulating in the exhibition, it might provide an impetus to study harder. Anyway, she might well have come across such an explanation in her teaching manual, and then it had occurred to her to try it on her son.

He wasn’t keen to go to the exhibition, thinking that nuclear power was the same thing as the nuclear bomb. (Pika-don in Japanese – pika; flashing and don; the sound of a bomb exploding). He had seen many times the movie about the ‘Pika-don’ that exploded at Hiroshima. After seeing the movie, he felt that if you could escape the initial heat and radioactivity at the time of the explosion, it might be possible to survive. He often tried to think how he could avoid the immediate effects of a nuclear explosion. For example, what should he do if he were out in the open in the rice fields? He decided that the best thing to do in that case would be to shelter under the nearest bridge. What about if he were in the school playground? Well, then he imagined that he should make sure he was the first child to hide in the hollow of the trunk of the big willow that stood in the playground, as the children that were last to seek refuge there, and consequently were exposed to the outside, would surely perish.

This kind of speculation in his daily life developed his thinking powers, and greatly helped him later in life when he needed to do efficient scenario analysis in his work. Anyway, the thought of nuclear power and the bomb only conjured up miserable images, and he couldn’t understand why his mother wanted to go to the exhibition. Also, he felt it was strange to think that it was possible to use the power that had created the bomb for peaceful purposes. On top of that, his older and wiser sister, for whom the exhibition would have surely been more suitable, was not going. So he thought there was something suspicious about his mother’s proposal and refused to go.

‘After the exhibition, we’ll go and see your father at his shop, and then you’ll be able to eat his delicious ramen,’ his mother explained.

The two times a year that his father came home, he drunk sake all day and never played with his children. In fact, in the 11 years of his life, he’d only ever had two experiences of his father spending leisure time with him – once when they played records together, and the other time when they went fishing. Using his developing analyzing skills to weigh up the situation, he could see that there was very little chance that his father would spend any time with him, but he was still eager to see his father. Even after he became an adult, he still couldn’t understand why. However, he did like his father’s ramen very much, and he was fed up eating the same meals that his mother and sister prepared for him every day. So finally, he agreed to go to the exhibition – his mother’s tactics had worked.

They arrived at the exhibition, held in a sports center in the downtown area of the city. His mother said coldly to him, ‘I’m going to your father’s shop. We have many things to talk about so have a look round here and I’ll be back for you at 2pm.’ She pressed the ticket into his hand and pushed him towards the entrance. He actually didn’t mind being treated like this – without his mother he would be able to look around the exhibition freely.

For the eleven years since the war had ended, the city had been undergoing rebuilding on a grand scale, and there was still an atmosphere of instability. Entering the hall from the dusty street, he was overwhelmed by the striking primary colors and brilliant illumination of the displays. He had never seen anything like it before. It reminded him of a bright scene in the one American movie he had seen. It all seemed very far from the misery caused by the atomic bomb in Hiroshima and Nagasaki, and this bewildered him.

‘Look! This amount of charcoal will only keep you warm for a short while, or heat one saucepan,’ one of the exhibition staff cheerfully explained to him, holding out his hand to show how much charcoal he meant. ‘The amount we could hold in both hands would be enough to melt even iron,’ he continued. This reminded the boy of the blacksmith’s hearth in the outskirts of his town. ‘And if we used an amount ten times greater still, it would make a huge fire. Well, it’s the same thing with nuclear power. A large amount could be used to make an atomic bomb, but smaller amounts can be used for peaceful purposes – fuel, for example.’ The boy partly understood but also felt he was being misled. This must have shown on his face because the man’s smile disappeared and he continued his explanation in a rather stern manner.

‘The carbon atoms contained in charcoal react with oxygen in the air during burning and become carbon dioxide, while generating heat. It’s called a chemical reaction, but nuclear power is different. An atom is composed of an atomic nucleus and the electrons moving around it. The atomic nucleus itself is a mass of very small particles called protons and neutrons. There are two types of atom for the element uranium – uranium 225 and uranium 238. This number represents the number of protons in the nucleus. When neutrons collide with the nucleus of uranium 235, the nucleus breaks into pieces. This is called nuclear fission. Moreover, the neutrons emitted from the nucleus during nuclear fission collide with other nucleuses and break them into pieces again. This reaction, arising one after another, is called a chain reaction. The fission of the nucleus generates a gigantic amount of heat. The efficiency of electrical power generated in this way is much greater than hydroelectric or thermal power generation – an enormous amount of electricity being produced with just a tiny amount of uranium.’

Of course, it’s not a very precise explanation, but the man must have chosen his words carefully so that even an ignorant child could understand. Indeed, the boy didn’t understand completely but he was starting to feel that this all represented the birth of a new world, even if he still couldn’t forget the sad impression that the movie “Pika-don” had created.

So he asked the man nervously, ‘ In the ‘Pika-don’ movie, radiation killed many people – What about with nuclear power generation?’

‘Good question, ’ the man praised the boy for what must have been a frequently asked question. ‘Of course,’ he continued, ‘nuclear fission produces radiation, but that part of the process is encapsulated in a sturdy metal container, and the radiation is contained by thick walls of lead lining the container. Once the use of nuclear power spreads, it will free us of dependence on charcoal and coal for ever.’ Now, at the end of his explanation, the man suddenly became more cheerful and started smiling again. The boy thought it was strange that his attitude changed so abruptly but he understood that nuclear power would somehow be the savior of a Japan still trying to recover from the disasters the war had wrought.

The words the man had used – atomic nucleus, uranium 235, nuclear fission, chain reaction, radioisotope etc. were flying around his brain, even while eating lunch or listening to explanations at other booths.

He was brought back to reality by his mother’s voice, ‘Are you OK? – You look lost in thought.’ All the way from the exhibition place to the station, he walked after his mother, too taken up with thoughts of nuclear power to think about his father’s ramen. She was worried by his appearance, so much so that she kept turning round to ask him again and again, ‘Are you alright?’ But his expression didn’t change. Ordinarily, she didn’t pay much attention to his feelings, so she must have been feeling guilty about leaving him by himself for half the day.

He remained absorbed in the day’s happenings until they passed through the ticket barrier and took their seats on the train. After the train pulled out of the station, the town came into view through the window. It might seem strange for a child to have such a feeling but he hated this moment the most – leaving the city and returning to the gloom of daily life in his own town. Moreover, it somehow made him sad to think that many people were struggling to eke out a living in the busy city.

That day, his melancholy mood looked like it would get worse, until the moment when his town came into view, and he cried out, ‘Yes!’ Surprised by his shout, his mother asked him in a similarly loud voice, ‘What’s the matter?’ He was so fascinated by the new idea he now had that he again ignored her question.

Before entering primary school, (There was no kindergarten in his village) he used to while away his free time reading fairy tales by Grimm, Anderson, Rabelais (Gargantuan and Pantagruel) etc., which aroused his interest in European countries. At that time, he had a dream about visiting Europe in the future as a diplomat. However, because he had been bullied at primary school, he had a morbid fear of meeting new people, and this took the edge of any happiness that the dream might have given him. On top of that, he really did not like himself very much and had been struggling to find a raison d’etre’ for about 5 years.

His cry signified the moment he was released from that agony. He saw that the purpose of his life would be to become a nuclear scientist and contribute to society through the peaceful use of nuclear power.

‘Mom, I’m hungry – Do you have anything to eat?’ he asked her all of a sudden.

‘What’s made you so hungry? Anyway, you can have some of these,” she said as she passed the box of macaroons (a sweet cookie) to him, still feeling guilty about leaving him alone, no doubt. He filled his mouth with the delicious cookies – delicious because the impact of science had taken away the gloom of five years!

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