Reding Gapped Text

Reading: Gapped text Exercise 1

Living in a Dream World Daydreaming can help solve problems, trigger creativity, and inspire great works of art and science. By Josie Glazier. Most people spend between 30 and 47 per cent of their waking hours spacing out, drifting off, lost in thought, wool-gathering or building castles in the air. Yale University emeritus psychology professor Jerome L. Singer defines daydreaming as shifting attention “away from some primary physical or mental task toward an unfolding sequence of private responses” or, more simply, “watching your own mental videos.” He also divides daydreaming styles into two main categories: “positive-constructive,” which includes upbeat and imaginative thoughts, and “dysphoric,” which encompasses visions of failure or punishment. 119. Such humdrum concerns figured prominently in one study that rigorously measured how much time we spend mind wandering in daily life. In a 2009 study, Kane and his colleague Jennifer McVay asked 72 students to carry Palm Pilots that beeped at random intervals eight times a day for a week. The subjects then recorded their thoughts at that moment on a questionnaire. The study found that about 30 per cent of the beeps coincided with thoughts unrelated to the task at hand and that mind-wandering increased with stress, boredom or sleepiness or in chaotic environments and decreased with enjoyable tasks. That may be because enjoyable activities tend to grab our attention. 120.

B

We may not even be aware that we are daydreaming. We have all had the experience of “reading” a book yet absorbing nothing—moving our eyes over the words on a page as our attention wanders and the text turns into gibberish. “When this happens, people lack what I call ‘meta-awareness,’ consciousness of what is currently going on in their mind,” he says. But aimless rambling can be productive as they can allow us to stumble on ideas and associations that we may never find if we intentionally seek them. 121.

G

So, why should daydreaming aid creativity? It may be in part because when the brain is floating in unfocused mental space it serves a specific purpose. It allows us to engage in one task and at

the same time trigger reminders of other, concurrent goals so that we do not lose sight of them. There is also the belief that we can boost the creative process by increasing the amount of daydreaming we do or replaying variants of the millions of events we store in our brains. 122. The mind's freedom to wander during a deliberate tuning out could also explain the flash of insight that may coincide with taking a break from an unsolved problem. A study conducted at the University of Lancaster in England into this possibility found that if we allow our minds to ramble during a moderately challenging task, we can access ideas that are not easily available to our conscious minds. Our ability to do so is now known to depend on the normal functioning of a dedicated daydreaming network deep in our brain. 123. It was not until 2007, however, that cognitive psychologist Malia Fox Mason, discovered that the default network — which lights up when people switch from an attention-demanding activity to drifting reveries with no specific goals, becomes more active when mind wandering is more likely. She also discovered that people who daydream more in everyday life show greater activity in the default network while performing monotonous tasks. 124. The conclusion reached in this ground-breaking study was that the more complex the mind wandering episode is, the more of the mind it is going to consume. This inevitably leads to the problem of determining the point at which creative daydreaming crosses the boundary into the realms of compulsive fantasising. Although there is often a fine dividing line between the two, one question that can help resolve the dilemma relates to whether the benefits gained from daydreaming outweigh the cost to the daydreamer’s reputation and performance. 125. On the other hand, there are psychologists who feel that the boundary is not so easily defined. They argue that mind wandering is not inherently good or bad as it depends to a great extent on context. When, for example, daydreaming occurs during an activity that requires little concentration, it is unlikely to be costly. If, however, it causes someone to suffer severe injury or worse by say, walking into traffic, then the line has been crossed.

A Although these two findings were significant, mind wandering itself was not measured during the scans. As a result, it could not be determined exactly when the participants in her study were “on task” and when they were daydreaming. In 2009 Smallwood, Schooler and Kalina Christoff of the University of British Columbia published the first study to directly link mind wandering with increased activity in the default network. Scans on the participants in their study revealed activity in the default network was strongest when subjects were unaware they had lost focus.

B However, intense focus on our problems may not always lead to immediate solutions. Instead allowing the mind to float freely can enable us to access unconscious ideas hovering underneath the surface — a process that can lead to creative insight, according to psychologist Jonathan W. Schooler of the University of California, Santa Barbara

C

Yet to enhance creativity, it is important to pay attention to daydreams. Schooler calls this “tuning out” or deliberate “off-task thinking.”, terms that refer to the ability of an individual to have more than just the mind-wandering process. Those who are most creative also need to have meta-awareness to realise when a creative idea has popped into their mind.

D

On the other hand, those who ruminate obsessively—rehashing past events, repetitively analyzing their causes and consequences, or worrying about all the ways things could go wrong in the future - are well aware that their thoughts are their own, but they have intense difficulty turning them off. The late Yale psychologist Susan Nolen-Hoeksema does not believe that rumination is a form of daydreaming, but she has found that in obsessive ruminators, the same default network as the one that is activated during daydreaming switches on.

E

Other scientists distinguish between mundane musings and extravagant fantasies. Michael Kane, a cognitive psychologist at the University of North Carolina at Greensboro, considers “mind wandering” to be “any thoughts that are unrelated to one's task at hand.” In his view, mind wandering is a broad category that may include everything from pondering ingredients for a dinner recipe to saving the planet from alien invasion. Most of the time when people fall into mind-wandering, they are thinking about everyday concerns, such as recent encounters and items on their to-do list.

F

According to Schooler, there are two steps you need to take to make the distinction. First, notice whether you are deriving any useful insights from your fantasies. Second, it is important to take stock of the content of your daydreams. To distinguish between beneficial and pathological imaginings, he adds, “Ask yourself if this is something useful, helpful, valuable, pleasant, or am I just rehashing the same old perseverative thoughts over and over again?” And if daydreaming feels out of control, then even if it is pleasant it is probably not useful or valuable.

G

Artists and scientists are well acquainted with such playful fantasizing. Filmmaker Tim Burton daydreamed his way to Hollywood success, spending his childhood holed up in his bedroom, creating posters for an imaginary horror film series. Orhan Pamuk, the Turkish novelist who won the Nobel Prize in Literature in 2006, imagined “another world,” to which he retreated

as a child, Albert Einstein pictured himself running along a light wave—a reverie that led to his theory of special relativity.

H

Like Facebook for the brain, the default network is a bustling web of memories and streaming movies, starring ourselves. “When we daydream, we're at the center of the universe,” says neurologist Marcus Raichle of Washington University in St. Louis, who first described the network in 2001. It consists of three main regions that help us imagine ourselves and the thoughts and feelings of others, draw personal memories from the brain and access episodic memories.

Exercise 2

HELP GUIDE US THROUGH THE UNIVERSE Sir Martin Rees, Astronomer Royal, launches this year's Young Science Writer competition If you ask scientists what they're doing, the answer won't be 'Finding the origin of the universe', 'Seeking the cure for cancer' or suchlike. It will involve something very specialised, a small piece of the jigsaw that builds up the big picture. 119.

So, unless they are cranks or geniuses, scientists don't shoot directly for a grand goal - they focus on bite-sized problems that seem timely and tractable. But this strategy (though prudent) carries an occupational risk: they may forget they're wearing blinkers and fail to see their own work in its proper perspective. 120.

I would personally derive far less satisfaction from my research if it interested only a few other academics. But presenting one's work to non-specialists isn't easy. We scientists often do it badly, although the experience helps us to see our work in a broader context. Journalists can do it better, and their efforts can put a key discovery in perspective, converting an arcane paper published in an obscure journal into a tale that can inspire others. 121.

On such occasions, people often raise general concerns about the way science is going and the impact it may have; they wonder whether taxpayers get value for money from the research they support. More intellectual audiences wonder about the basic nature of science: how objective can we be? And how creative? Is science genuinely a progressive enterprise? What are its limits and are we anywhere near them? It is hard to explain, in simple language, even a scientific concept that you understand well. My own (not always effective) attempts have deepened my respect for science reporters, who have to assimilate quickly, with a looming deadline, a topic they may be quite unfamiliar with. 122.

It's unusual for science to earn newspaper headlines. Coverage that has to be restricted to crisp newsworthy breakthroughs in any case distorts the way science develops. Scientific advances are usually gradual and cumulative, and better suited to feature articles, or documentaries - or even books, • for which the latent demand is surprisingly strong. For example, millions bought A Brief History of Time, which caught the public imagination. 123.

Nevertheless, serious hooks do find a ready market. That's the good news for anyone who wants to enter this competition. But books on pyramidology, visitations by aliens, and suchlike do even better: a symptom of a fascination with the paranormal and 'New Age' concepts. It is depressing that these are often featured uncritically in the media, distracting attention from more genuine advances. 124.

Most scientists are quite ordinary, and their lives unremarkable. But occasionally they exemplify the link between genius and madness; these 'eccentrics' are more enticing biographees. 125.

There seems, gratifyingly, to be no single 'formula' for science writing - many themes are still under-exploited. Turning out even 700 words seems a daunting task if you're faced with a clean sheet of paper or a blank screen, but less so if you have done enough reading and interviewing on a subject to become inspired. For research students who enter the competition, science (and how you do it) is probably more interesting than personal autobiography. But if, in later life, you become both brilliant and crazy, you can hope that someone else writes a best-seller about you.

A. However, over-sensational claims are a hazard for them. Some researchers themselves 'hype up' new discoveries to attract press interest. Maybe it matters little what people believe about Darwinism or cosmology. But we should be more concerned that misleading or over-confident claims on any topic of practical import don't gain wide currency. Hopes of miracle cures can be raised; risks can be either exaggerated, or else glossed over for commercial pressures. Science popularisers perhaps even those who enter this competition - have to be as skeptical of some scientific claims as journalists routinely are of politicians.

B. Despite this there's a tendency in recent science waiting to be chatty, laced with gossip and biographical detail. But are scientists as interesting as their science? The lives of Albert Einstein and Richard Feyman are of interest, but is that true of the routine practitioner?

C. Two mathematicians have been treated as such in recent books: Paul Erdos, the obsessive itinerant Hungarian (who described himself as 'a machine for turning coffee into theorems') and John Nash, a pioneer of game theory, who resurfaced in his sixties, after 30 years of insanity, to receive a Nobel prize.

D. For example, the American physicist Robert Wilson spent months carrying out meticulous measurements with a microwave antenna which eventually revealed the 'afterglow of creation' the 'echo' of the Big Bang with which our universe began. Wilson was one of the rare scientists with the luck and talent to make a really great discovery, but afterwards he acknowledged that its importance didn't sink in until he read a 'popular' description of it in the New York Times.

E.

More surprising was the commercial success of Sir Roger Penrose's The Emperor's New Mind. This is a fascinating romp through Penrose's eclectic enthusiasms - enjoyable and enlightening. But it was a surprising best seller, as much of it is heavy going. The sates pitch 'great scientist says mind is more than a mere machine' was plainly alluring. Many who bought it must have got a nasty surprise when they opened it.

F. But if they have judged right, it won't be a trivial problem - indeed it will be the most difficult that they are likely to make progress on. The great zoologist Sir Peter Medawar famously described scientific work as 'the art of the soluble'. 'Scientists,' he wrote, 'get no credit for failing to solve a problem beyond their capacities. They earn at best the kindly contempt reserved for utopian politicians.'

G.

This may be because, for non-specialists, it is tricky to demarcate well-based ideas from flaky speculation. But its crucially important not to blur this distinction when writing articles for a general readership. Otherwise credulous readers may take too much on trust, whereas hardnosed skeptics may reject all scientific claims, without appreciating that some have firm empirical support.

H. Such a possibility is one reason why this competition to encourage young people to take up science writing is so important and why I am helping to launch it today. Another is that popular science writing can address wider issues. When I give talks about astronomy and cosmology, the questions that interest people most are the truly `fundamental' ones that I can't answer: 'Is there life in space?', Is the universe infinite?' or 'Why didn't the Big Bang happen sooner?'

Exercise 3

WELCOME TO ECO-CITY The world has quietly undergone a major shift in balance. According to UN estimates, 2008 marked the first year in history when more than half of the world's population lived in cities. There are now around 3.4bn human beings stuffed into every available corner of urban space, and more are set to follow. At a time when humanity has woken up to its responsibility to the environment, the continuing urban swell presents an immense challenge. In response, cities all over the world are setting themselves high targets to reduce carbon emissions and produce clean energy. But if they don't succeed, there is another option: building new eco-cities entirely from scratch. 119.

`Rather than just design a city in the same way we'd done it before, we can focus on how to minimise the use of resources to show that there is a different way of doing it', says Roger Wood, associate director at Arup. Wood is one of hundreds of people at Arup, the engineering and architecture giant, hired by Shanghai Industrial Investment Corporation to set out a master plan for the Dongtan eco-city. 120.

When the first demonstrator phase is complete, Dongtan will be a modest community of 5000. By 2020, that will balloon to 80,000 and in 2050, the 30km2 site will be home to 500,000. Arup says that every one of those people will be no more than seven minutes' walk from public transport. Only electric vehicles will be allowed in the city and residents will be discouraged from using even those because each village is planned so that the need for motorised transport is minimal. 121.

That's a big cornerstone of Arup's design for Dongtan. The aim is that the city will require 66 percent less energy than a conventional development, with wind turbines and solar panels complementing some 40 percent that comes from biological sources. These include human sewage and municipal waste, both of which will be controlled for energy recovery and composting. Meanwhile, a combined heat and power plant will burn waste rice husks.

122.

Work on Dongtan had been scheduled to begin in late 2008 with the first demonstration phase completed by 2010. Unfortunately, problems resulting from the complicated planning procedures in China have led to setbacks. Dongtan's rival project in Abu Dhabi has suffered no such holdups. Engineers broke ground on the Masdar eco-city in March 2008. Although it will take a different approach in terms of design, like Dongtan, the city is planned to be a zero-carbon, uberefficient showcase for sustainable living. 123.

In the blistering desert of the Gulf state, where it's almost too hot to venture outdoors for three or four months of the year, the big question for Masdar is how to keep cool without turning on the air-conditioning. In this equation, insulation and ventilation suddenly become more important than the performance of solar panels. To maximise shade, I the city's streets are packed closely together, with limits of four or five storeys set on the height of most buildings. 124.

The other major design feature for Masdar is that the whole city is raised on a deck. The pedestrian level will be free of vehicles and much of the noisy maintenance that you see in modern cities. Cars are banned from Masdar entirely, while an underground network of `podcars' ferries people around the city. 125.

Given that this concern is legitimate, developers of both cities would do well to incorporate both a range of housing and jobs to make them inclusive to everyone. This will be difficult, obviously, but then just about everything is difficult when you're completely reinventing the way we build and live in a metropolis. And supposing these sustainable and super-efficient cities are successful, could they even usher in a new world order?

A. The city will be built on a corner of Chongming Island in the mouth of the Yangtze River. It will be made up of three interlinked, mixed-use villages, built one after the other. Each will

combine homes, businesses and recreation, and a bridge and tunnel link will connect the population with Shanghai on the mainland.

B. The skin of each building will be crucial. Thick concrete would only soak up heat and release it slowly, so instead engineers will use thin walls that react quickly to the sun. A thin metal layer on the outside will help to reflect heat and stop it from penetrating the building. Density is also critical for Masdar. The city is arranged in a definite square with a walled border. Beyond this perimeter, fields of solar panels, a wind farm and a desalination plant will provide clean energy and water, and act as a barrier to prevent further sprawl.

C. 'If you plan your development so people can live, work and shop very locally, you can quite significantly reduce the amount of energy that's being used', Wood says. `Then, not only have you made the situation easier because you've reduced the energy demand, but it also means that producing it from renewable sources becomes easier because you don't have to produce quite as much'.

D. Arup's integrated, holistic approach to city planning goes further still. Leftover heat from the power plant will be channelled to homes and businesses. Buildings can be made of thinner materials because the electric cars on the road will be quiet, so there's less noise to drown out. Dongtan will initially see an 83 per cent reduction in waste sent to landfill compared to other cities, with the aim to reduce that to nothing over time. And more than 60 per cent of the whole site will be parks and farmland, where food is grown to feed the population.

E. Developers at Masdar and Dongtan are adamant that each city will be somewhere that people want to live. Critics do not question this but they do, nevertheless, wonder if these cities will be realistic places for people on a low income. They say that it would be easy for places like these to become a St Tropez or a Hamptons, where only rich people live.

F. Funded by a 12bn (euro) investment from the government in Abu Dhabi, it has not passed the attention of many observers that Masdar is being built by one of the world's largest and most profitable producers of oil. Even so, under the guidance of architects as Foster and Partners, the city is just as ambitious as its Chinese counterpart and also hinges on being able to run on low power.

G. Since cars and other petrol-based vehicles are banned from the city, occupants will share a network of ‘podcars' to get around. The 'personal rapid transit system' will comprise 2500 driverless, electric vehicles that make 150,000 trips a day by following sensors along a track beneath the pedestrian deck. Up to six passengers will ride in each pod: they just hop in at one of 83 stations around the city and tap in their destination.

H. Incredibly, this is already happening. Two rival developments, one in China and one in the United Arab Emirates, are progressing in tandem. Work on Masdar, 17km from Abu Dhabi, began in 2008, while Dongtan, near Shanghai, will eventually be home to half a million people. The aim for both is to build sustainable, zero-carbon communities that showcase green technology and demonstrate what smart urban planning can achieve in the 21st century.

Exercise 4:

The Rise of Silicon Valley On January 11, 1971, an article was published in the trade newspaper Electronic News about the companies involved in the semiconductor and computer industries in Santa Clara Valley at the southern end of San Francisco Bay Area in California, USA. The article was entitled 'Silicon Valley USA', a reference to the fact that silicon is the most important substance used in commercial semiconductors and their applications. The name stuck, and in light of the commercial success of the companies there, 'Silicon Valley' is now used as a metonym for the high-tech sector. 119.

One such new business was the one founded by two graduates of the nearby Stanford University called Bill Hewlett and David Packard. In 1938 the pair had $538, and along with Dave's wife Lucile, decided to rent a property at 367 Addison Avenue, Palo Alto. For $45 a month they got a ground floor apartment for Dave and Lucile, a garden shed where Bill slept, and a garage from which to run the business, a garage which has more recently been dubbed 'The birthplace of Silicon Valley'. 120.

As time passed, the 200A was improved and developed, resulting in the 200B. Eight of these improved oscillators were bought by The Walt Disney Company, for use in testing and certifying the Fantasound surround-sound systems installed in cinemas for the 1940 movie Fantasia. Success was beginning to come. 121.

Although they are often considered to be the symbolic founders of Silicon Valley, they did not deal in semiconductor devices until the 1960s. From then onwards, the semiconductor devices they made were mostly intended for internal use, for such products as measuring instruments and calculators. Today, however, Hewlett-Packard is the largest manufacturer of personal computers in the world. 122.

Terman also had a more direct influence through his role at Stanford University. The University had been established in 1891 in the north-western part of the Santa Clara Valley, and from the start, its leaders aimed to support the local region. The result was that the University played an important part in establishing and developing local businesses, and indeed its alumni went on to found some major companies, not just Hewlett-Packard, but such household names as Yahoo! and Google. 123.

Terman's proposal was taken up by Stanford University, and in 1951 Stanford Industrial Park was created. The first tenant in the Park was Varian Associates, founded by Stanford alumni in the 1930s to make components for military radars. Hewlett-Packard moved in two years later. The Park still flourishes to this day, although it is now known as Stanford Research Park. Current tenants include Eastman Kodak, General Electric and Lockheed Corporation. 124.

The 1950s were also a time of great development in electronics technology. Most importantly, the development of the transistor continued. Research scientist William Shockley moved to the Santa Clara Valley region in 1956, when he formed Shockley Semiconductor Laboratory. There his research team started constructing semiconductors from silicon, rather than germanium, as did most other researchers. The silicon transistors proved to perform much better, and started to be used in radios and the early computers. 125.

Since the 1970s, however, the most important developments pioneered in Silicon Valley have been in software and Internet services rather than hardware. So even though Hewlett-Packard remains the largest producers of computers in the world, the future of Silicon Valley might well lie elsewhere.

A. Throughout their early years, Hewlett and Packard were mentored by one of their university professors, Frederick Terman. Terman was Stanford University's dean of engineering and provost during the 1940s and 1950s, and had a positive influence on many of the successful companies in Silicon Valley. Indeed, his influence was such that he has been dubbed 'the father

of Silicon Valley'. Terman encouraged his students to form their own companies and personally invested in many of them, and in this way nurtured many highly successful companies, including not just Hewlett-Packard, but others such as Varian Associates and Litton Industries.

B.

Hewlett-Packard was arguably the first company to offer a mass-produced personal computer, namely the 9100A. For marketing reasons, however, the 9100A was sold as a 'desktop calculator'. It simply did not resemble what was then considered a 'computer', namely the large machines being sold by IBM. The 9100A fitted comfortably on a desk, and possessed a small screen and a keyboard. In fact, it was more like an oversized and over-expensive precursor of a pocket calculator than a modern PC, since its keyboard lacked letter keys.

C. Following the end of the Second World War in 1945, universities in the United States were experiencing enormous enrolment demands from the returning military personnel. Terman proposed launching a scheme which would kill two birds with one stone. The idea was to lease out land owned by Stanford University to high-technology companies for their offices. This scheme would firstly finance the University's growth requirements and thereby facilitate a larger student intake, and secondly provide local employment opportunities for graduating students.

D. The beginnings of Silicon Valley can be traced back to the early twentieth century. At that time, Santa Clara Valley was known for its orchards which flourished in California's balmy climate. There were nevertheless a number of experimenters and innovators in such fields as radio, television and military electronics, and several people were trying to take advantage of any business opportunities that might arise.

E. It was also in Silicon Valley that other revolutionary electronic components were developed. The silicon-based integrated circuit, the microprocessor and the microcomputer were all invented by companies there, as well as such electronic devices as the mouse and the ink-jet printer. Indeed, Silicon Valley has been the world's most important site of electronic innovation over the past 50 years.

F. In those early years, Hewlett-Packard was a company without a focused direction. They made a whole range of electronic products, with diverse customers in industry and agriculture. In the 1940s, their principal products were test equipment, including such devices as voltmeters, oscilloscopes and thermometers. They aimed to provide better quality products than their competitors, and made a big effort to make their products more sensitive and accurate than their rivals.

G.

Another bond between the University and the local high-technology businesses was established in 1954, with the creation of the Honors Cooperative Program. This programme allowed employees of the businesses to pursue part-time graduate degrees at the University

whilst continuing to work full-time in their jobs. In this way, key workers in the electronics industry were able to hone their skills and knowledge, creating the foundation for the development of Silicon Valley.

H. Of the many products Hewlett and Packard worked on, the first financially successful one was a precision audio oscillator, a device for testing sound equipment. This product, the 200A, featured the innovative use of a small light bulb as a temperature-dependent resistor in a critical section of the circuit, which allowed them to sell it for $54.40, only a quarter of the price of their competitors' audio oscillators.

Exercise 5

Rainmaker with his Head in the Clouds Critics dismissed Craeme Mather's attempts to make clouds rain. But now recent experiments appear to have vindicated him. Anjana Ahuya reports. Dr. Craeme Mather lived his life with his head in the clouds, as a documentary film to be shown this week shows. Against the advice of almost everybody else in the meteorological community, the Canadian scientist devoted his professional life to trying to make clouds rain.

119.

Before Dr. Mather became involved, the science of weather modification had already claimed many reputations. The idea that clouds could be manipulated first circulated in the 1940s, and efforts gathered pace soon after the Second World War. 120.

However, the entire discipline fell into disrepute when commercial companies hijacked the idea, took it around the world, and then failed to deliver on their promises. Cloud-seeding, as the process was known, became the preserve of crackpots and charlatans.

121.

Scientists theorized that if they could inject the cloud with similarly shaped crystals, these imposter crystals would also act as frames around which droplets would clump. The cloud would then be tricked into raining. Silver iodide, whose crystals resemble those of ice, seemed the best bet. Sadly, none of the experiments, including Dr. Mather's, which had been going for more than five years, seemed to work. Dr. Mather was about to admit defeat when serendipity intervened. 122.

Dr. Mather was convinced that something that the place was spewing into the atmosphere was encouraging the downpour. Subsequent experiments confirmed that hygroscopic salts pouring into the sky from them were responsible. Hygroscopic salts attract water - once in the atmosphere, the particles act as magnets around which raindrops can form.

123.

He was wary; Dr. Mather was known to be a smooth-talking salesman. 'He was charming and charismatic, and many scientists don't trust that; he says. 'He was also not well-published because he had been working in the commercial sector. Overall, he was regarded as a maverick. On that occasion, he presented results that I was convinced were impossible. Yet the statistical evidence was overwhelming, which I couldn't understand. 124.

'If those findings can be reproduced there, it will be the most exciting thing to have happened in the field for 20 years. It will be remarkable because some of the results are not scientifically explainable.’ He adds, however, that scientists must exercise caution because cloud-seeding is still mired in controversy. He also points out that, with water being such a precious resource, success will push the research into the political arena. 125.

Dr. Cooper says: 'With the paper mill, he saw something that other people wouldn't have seen. I am still uncomfortable with his idea because it throws up major puzzles in cloud physics. But if Dr. Mather was right, it will demonstrate that humans can change clouds in ways that were once thought impossible.'

A

Dr. Mather refused to be daunted by this image. After all, the principle seemed perfectly plausible. Water droplets are swept up to the top of the clouds on updrafts, where they become supercooled (i.e., although the temperature is below freezing, the water remains liquid). When a supercooled droplet collides with an ice crystal, it freezes on contact and sticks. Successive collisions cause each ice crystal to accumulate more water droplets; the crystals grow until they become too heavy to remain suspended in the atmosphere. As the crystals fall through the cloud, they become raindrops. The ice crystals, therefore, act as frames to 'grow' raindrops.

B

Dr. Mather, unfortunately, will not be involved in the debate about such matters. He died aged 63, shortly before the documentary was completed. It will ensure that this smooth-talking maverick is given the recognition he deserves.

C

He and a colleague decided to collect a last batch of data when they flew into a tiny but ferocious storm. That storm, Dr. Mather says in the film, changed his life. Huge droplets were spattering on the tiny plane's windscreen. No such storm had been forecast. Back on the ground, they discovered the storm was located directly above a paper mill.

D

A trial in Mexico has been running for two years, and the signs are promising. 'We were sufficiently encouraged in the first year to continue the seeding research. But the results are preliminary because we have only a very small sample of clouds at the moment. We need to work over two more summers to reach a proper conclusion.

E

He arranged to fly to South Africa 'with the full intention of explaining what was wrong with the experiment'. Instead, he came back convinced that Dr. Mather was on to something. He is now running two experiments, one in Arizona and one in northern Mexico to try to verify the South African results. The experiments use potassium chloride, which is similar to table salt (sodium chloride) and, it is claimed, non-polluting.

F

The scientific community remained sniffy in the face of this apparent proof. Foremost among the skeptics was Dr. William Cooper, of the United States National Centre for Atmospheric Research (NCAR). Dr. Cooper, regarded as one of the world's finest cloud scientists, saw Dr. Mather present his astonishing claims at a cloud physics conference in Montreal.

G They involved weather experts firing rockets into clouds to stop them from producing hail, which damages crops. The clouds, it was hoped, would dissolve into a harmless shower.

H

The desire to do so led him to set up a project in South Africa, which was ultimately to convince him that it was possible. As the program reveals, experiments around the world appear to prove his faith was justified.