Over a quarter of us have an opening in the wall separating the upper chambers of the heart. This opening, known as a patent foramen ovale, is a relic of our days in the womb, when it allows blood to bypass the lungs.

It should snap shut with a baby鈥檚 first breath, but it does not always close up completely. Large holes can continue to allow small amounts of blood from the veins to bypass the lungs.

A decade ago, Peter Wilmshurst, now at the Royal Shrewsbury Hospital, found that many divers who are particularly vulnerable to the bends have these holes, and more than half of them had holes over 11 millimetres across (New 杏吧原创, 20 May 1989, p 30).

This means that any bubbles that form in veins as divers ascend can pass through the hole and enter the arteries, where they can block capillaries in the brain or spinal cord. Normally, the lungs would filter out such bubbles.

Wilmshurst also noticed that these divers tend to have a history of migraines preceded by an 鈥渁ura鈥� of visual and speech disturbances or changes in skin sensation. Out of 80 divers with large holes, he found that 40 suffered from this kind of migraine.

Many such divers decide to have the hole closed to reduce their chances of suffering from the bends. The operation can be performed via a catheter inserted into the heart. To Wilmshurst鈥檚 surprise, seven out of 16 divers who had surgery to close the holes stopped having migraines altogether, and all but one of the other nine reported that their migraines had become less severe and less frequent.

Anne MacGregor of the City of London Migraine Clinic says that the findings fit in with research suggesting that the aura preceding some migraines is caused by minute blood clots lodging in vessels in the visual cortex and restricting the flow of blood.

鈥淭he loss of the filter mechanism of the lungs could account for the temporary restriction in blood flow seen during migraine aura, which may be why young people with migraine aura have an increased risk of stroke,鈥� she says.

鈥淭he role of the lungs as a filter for the blood may be far more important than anyone expected,鈥� says Wilmshurst. 鈥淚t鈥檚 known that small blood clots which can form in the veins get trapped in the capillaries of the lungs and this is believed to protect against stroke.鈥�

The lungs may also remove any vasoactive chemicals 鈥� substances that cause blood vessels to dilate or contract 鈥� present in venous blood, which are believed to trigger migraines.

Wilmshurst says more research should be done to find out how common it is for people who suffer severe migraines to have a hole in the heart.

More at: Clinical Science (vol 100, p 215)

Reading and enjoying Wild Technology by Phil Gates (Kingfisher, 拢12.99, ISBN 1 85697 324 7) has helped me to put my finger on the reasons I find science pleasurable. With the help of beautiful photographs and illustrations, Gates shows how a wide range of engineering problems have been solved. And he demonstrates that living organisms have often evolved identical solutions when faced with similar problems to human engineers. Armour used by knights looks and acts like the tough plates that woodlice have on their backs. Teachers who wring their hands at the way the National Curriculum artificially compartmentalises different subjects will love this book. Gates makes science and technology flow together seamlessly, as they do in real life, and applies them both to natural history.

The thing that makes Gates鈥檚 book especially good is that he doesn鈥檛 just present the facts. He helps readers to think about those things in a different way and find links that aren鈥檛 obvious. I don鈥檛 think I鈥檓 the only person to get pleasure from this kind of mental exercise. This is a large part of the pleasure that adults get from doing science and reading about it. Yet amazingly, only a tiny proportion of children鈥檚 science books even attempt to entice their young readers in this way.

Dorling Kindersley鈥檚 books, with their exquisitely crafted pages of photographs and drawings, are considered by many to be a gold standard of children鈥檚 information books. The problem is, that鈥檚 all they are 鈥� books containing information. Undoubtedly Eyewitness Guide: Gorilla (拢8.99, ISBN 0 7513 6058 9) will fascinate a child who is keen to find out about gorillas and it should prove quite useful for projects. It has delightful pictures of all sorts of primates, each with a caption that provides a chunk of information. One reads this book the way one strolls through the primate house of a zoo reading the signs associated with each exhibit. Afterwards, I felt I had learned a lot but was none the wiser.

That鈥檚 not to say information books don鈥檛 have a place. The Eyewitness Visual Dictionary of the Skeleton (Dorling Kindersley, 拢10.99, ISBN 0 7513 1060 3) allows the reader to observe in fine detail the structures that provide support and protection to plants, arthropods and molluscs, as well as vertebrates. It gives readers ample opportunity to see for themselves the patterns and contrasts that occur in nature, to speculate about their significance and start thinking analytically. But will young readers start spontaneously to speculate in this way? They may if they have had guidance from a parent or teacher, or a book that works harder to help them to see the stories behind the information.

The mental exercises of science are a development of the thought processes that very young children use as they explore the world and try to make sense of it. If we want to produce new science lovers, we should start as early as possible to introduce them to ideas that bend and stretch their minds. And So They Build (Walker, 拢4.99, ISBN 0 7445 3644 8) does this. It鈥檚 a beautifully illustrated story book by Bert Kitchen, which my eight-year-old daughter adored. The stories are about animals, each of which has a reason to build and so they do: a bower to impress a mate, a dam to create a pond, a web to trap insects, a nest to keep their babies safe.

For even younger children, try The Body by Nicola Edwards (A & C Black, 拢6.99, ISBN 0 7136 4241 6) 鈥� it鈥檚 nothing like the many other children鈥檚 books that bear this name. It鈥檚 part of a series called 鈥淢essages鈥� that uses pictures and simple words to point out the subtle messages we give out. We send messages with our body, helped by facial expressions, hand signals, clothes and body paint. Our body receives messages from the outside world and tells us how it is feeling. We become familiar with these messages at a very young age but our awareness of them is unconscious. Books like this, which encourage children to think about how they learn about their environment, are a good first step to a more sophisticated way of learning.

When things go right, he reveals in Divers, this is a pretty dull job. Day after day rolls by watching dials and making adjustments to keep the environment inside the chamber as comfortable as possible. Looking after the divers鈥� physical and psychological needs includes providing them with meals, books, videos and a sympathetic ear so their confinement in a few cubic metres of the voice-distorting helium gas doesn鈥檛 drive them round the bend.

But when things go wrong on a diving operation or on any work site where survival depends on technology, life gets very interesting very quickly. In 1988 May was working on a rig that was supporting a diving operation on the Piper field in the North Sea. He and his colleagues noticed the fire on the Piper Alpha platform while it was still a small blaze that should have been extinguished by the platform鈥檚 fire-controlling technology. A few minutes later he was part of the team trying to save the lives of the people on the platform.

May鈥檚 work also put him on ships operating from bases in Bombay, Sarawak and Kuwait. He was part of a team hired to find and destroy the mines that the Iraqis had attached to Kuwaiti oil platforms during the Gulf War. Alarming work, made more alarming by the local wildlife. A sea snake hissing with fury inside a mine casing sounds just like a mine about to explode. And the mine was on deck at the time.

Many books could be written about professional divers. Why are some men so attracted to these jobs? Why do they want to live in the company of other 鈥渞eal鈥� men, to take real risks and sweat real sweat? A book that explains the technology used or analyses the morality of decision-making in these industries would also be interesting. But May鈥檚 is an adventure book, a series of traveller鈥檚 tales that give a glimpse of the people and places he has encountered. If your adventures this summer will consist of relaxing with a good book, give this one a try. And try not to think of sea snakes when you nip in for a dip.

My Science Book of Weather by Neil Ardley

My Science Book of Movement by Neil Ardley

My Science Book of Gravity by Neil Ardley Dorling Kindersley, pp 32,
拢4.99

A Dorling Kindersley book is beautiful in the way that a glossy magazine
such as Vogue is beautiful. The cut-out photographs are well-lit and the
colour is just right. Each picture is explained in an adjacent box. The
result is an information book that delivers its message with the success
of Vogue鈥檚 advertisements for scent and mascara.

Style is so important to the popularity of Dorling Kindersley books
that it is not surprising the content of some of its publications has been
uninspired. In the case of these four books, however, the message matches
the polished delivery.

Neil Ardley and Jack Challoner have compiled a selection of activities
that will enable children to discover some of the less obvious properties
of our world. In Movement, Ardley explains how to build a paddleboat out
of an empty milk carton, cork, stiff plastic, two pencils and some rubber
bands. In Numbers, Challoner gives instructions on how to make things like
an abacus, a slide rule and, yes, a cardboard computer.

Admirers of the BBC鈥檚 Blue Peter know how much fun it is to get out
your scissors and glue. Children in junior school are the keenest makers
of things, and the activities in this book are aimed at their level of dexterity.
The activities demonstrate scientific concepts which, according to the National
Curriculum, are also appropriate to this age group. The clarity of style
means the instructions are easy to follow, while skilfully written text
explains the point behind each demonstration.

Some educationalists might argue that these books destroy the thrill
of discovery that children could get from a science lesson. All the demonstrations
have been done for you and photographed in exquisite detail, so why bother
to explore the world for yourself? The Dorling Kindersley style dictates
that most of the photos are completely without context in a white surround.
At the end of each section there is a small photo showing the concept demonstrated
operating in real life, but is this really enough?

Such criticisms are valid; these books should never be used on their
own to teach science. It is up to the teacher or parent to stimulate children
to carry out the demonstrations and play with the result. Afterwards, the
children can be helped to seek examples of the scientific concepts in the
world around them. These are good books and, in the hands of good teachers,
they will make a valuable contribution.

Lesley Newson writes science books for children.

Imagine that you are a GCSE student looking for a book to help you with
your project on environmental problems. You scan the shelf at the library
or bookshop and discover a modest paperback The Aliens Are Coming among
the colourful large format books.

Would you pick it up? If you did, you would find yourself confronted
with text. Indeed, some pages have no illustrations at all! The illustrations
are clear and some are funny but they are in black and white. Will many
GCSE students get past these obstacles and begin to read? Will teachers
and librarians who direct students toward books decide to challenge them
with a nonfiction book that has so many words in it?

I hope so, because this book is fun to read. It is full of stories,
explanations and fascinating facts to help you not only to learn about the
environment but also to think about it.

The 鈥榓liens鈥� that Phil Gates, a botanist, is talking about are plants
growing in places where they did not evolve. The soil in Britain for example,
already provides a home for vast numbers of aliens imported by the invaders
and explorers of past generations. More aliens are now on the way because
of global warming. In future, plants that evolved in warmer and drier places
may prove more successful than native British species. This may seem a
rather limited and obscure angle from which to view global warming. It isn鈥檛.
Gates makes it a terrific way find out about plants, how they live, how
they evolve and in between all this botany is enough physics to allow the
reader to understand what happens in a greenhouse.

How does he manage to turn all this potentially complex material into
a book that children can appreciate? Well, he is a good writer, he gives
loads of interesting examples and most of his explanations are accompanied
by 鈥榚xperiments鈥� designed to allow readers to discover how global warming
works and what its botanical repercussions may be.

Another thing that adds to the book鈥檚 readability is that the tone is
rather cheerful. Unlike most people who write about the environment, Gates
does not seem to want us to feel distressed, guilty or angry. Instead, he
makes us feel interested, challenged and even a little amused. He shows
us that we are part of the problem and tells us we could be part of the
solution. Readers are urged to become scientists and carry out 鈥榚xperiments鈥�
in the book because understanding the problem is the first step in finding
solutions.

I hope that GCSE students are beginning to tire of the picture book
format that publishers seem to think is the only way of getting science
into the apparently reluctant heads of schoolchildren. These books may be
great for attracting interest or raising awareness but, when it comes to
helping students to understand, a thousand words are often a lot better
than a picture. The Aliens Are Coming contains several thousand words that
are well worth reading.

Lesley Newson is a science writer based in Plymouth. Her latest children鈥檚
book is Stopping the Rot, published by Simon and Schuster.

For more than a generation, Britain鈥檚 children have been taught by teachers
who claim to be committed to the idea that education is about gaining understanding,
and not learning facts. But despite their efforts, the public still believe
that clever people know a lot.

No group clings to this idea more firmly than the pupils themselves.
It is fun to collect facts and even more fun to earn praise by demonstrating
that you can recite the names of 15 dinosaurs that lived during the Jurassic
and 27 which lived in the Cretaceous.

Ocean Facts is a good source of exactly the sort of unexpected and quotable
data that primary-schoolchildren like: plenty of statistics, lists and world
records. But children who begin reading the book to acquire this kind of
information will end up getting a lot more. They will get a quick glimpse
of hundreds of areas of scientific study and an intimation of the exciting
ideas they might contemplate as their study of science progresses.

That鈥檚 because Anita Ganeri has not limited herself to giving details
of giant killer sharks, epic sea journeys and poisonous sea serpents. Instead,
she tells her readers about the origins of the Earth, plate tectonics and
how mangroves manage to cope with living in salt water.

Ganeri attempts to explain such complicated ideas in less than 200 words,
which may well annoy some of the people who devote careers to their study.
But I cannot think of a better way of inspiring eight-year-olds to want
to join in them.

With a book containing information extracted and simplified from such
a wide variety of disciplines it is difficult to ensure that the facts are
actually true. I spotted one error, so I expect there are a few more. Normally,
this would annoy me intensely. Children deserve as high a standard of research
and writing as adults. But for some reason, it doesn鈥檛 bother me too much
in this case. Ocean Facts contains a great deal of information that is true
and a lot of fun to find out about.

Lesley Newson writes science books for children. Her latest are Down
The Drain and A Load of Rubbish, both published by Simon & Schuster
Young Books.

Today鈥檚 children, we are told, are fascinated by environmental issues
and concerned that they will inherit a dirty world. In response, educational
publishers have produced enough environmental literature during the last
18 months to mop up the average school鈥檚 budget for science books for the
next 18 years.

Philip Parker, a former information officer for Greenpeace and editor
of Greenpeace magazine, is an experienced environmental campaigner. And
Water for Life is an attractive well-illustrated book which presents his
views on the water pollution problem and how it should be solved. But what
place do these views have in the classroom?

The book is advertised as being appropriate for children of nine and
over. The national curriculum suggests that children of this age should
have an understanding of the water cycle, be aware that pollution can affect
survival of living organisms and know that the combustion of fuel produces
waste gases.

A great deal of further explanation is needed if children are to progress
from this point and achieve a real understanding of environmental issues.
But explanation is what this book seriously lacks.

Consider these three sentences taken in sequence from the first chapter:
鈥楶oisonous chemicals sprayed on fields by farmers can seep down through
the ground. In Britain much ground water has been badly polluted by farming
chemicals such as nitrates. This is serious because it supplies drinking
water for many people.鈥� No explanation is given of what nitrates are or
how dangerous it might be to drink water that contains nitrates. Children
are left to draw their own conclusions, the most likely one being that many
people in Britain are drinking water that is 鈥榖adly polluted鈥� with 鈥榩oisonous
肠丑别尘颈肠补濒蝉鈥�.

He goes on to catalogue water pollution problems created by industrialised
society: acid rain, beaches polluted by sewage, toxic industrial and radioactive
waste. What is missing is the explanation of why farmers use chemicals,
factories make waste and towns release sewage.

The problem is, of course, that environmental issues aren鈥檛 that simple.
They actually provide ideal subject matter for introducing children to a
more sophisticated and responsible way of viewing the world they will inherit.

The most important lesson for them to learn about the environment is
that we are all in part responsible. Children should be aware that the factories
producing the waste are making batteries for their Walkmans and fabrics
for their shellsuits. The farmers are using chemicals to make their food
cheap and parents鈥� water bills low.

Parker thinks of environmental issues more in terms of rights than responsibilities
. . . the right to safe drinking water, clean beaches, healthy wildlife
and so on. And, just as he presents the readers with villains to hiss at,
he gives them heroes to cheer. These are the campaigners who protest and
demand these rights.

No mention is made of the scientists and engineers attempting to understand
and find realistic solutions to pollution problems, solutions that might
satisfy the people鈥檚 demand for a healthy environment as well as all the
benefits of industrialisation.

There is a place in the classroom for Parker鈥檚 views, but only classrooms
where the pupils already understand the background to the issues he raises.
The precious science book budget of primary schools would be better spent
on educational material that helps them gain that understanding.

Lesley Newson writes on science for children. Her latest books are Down
the Drain and All that Rubbish.

鈥楢 Classroom Kit鈥� by R. Chase, Blackwell Education Pounds sterling 45

鈥楢n Early Start to Nature鈥� by R. Richards, Macdonald Educational pp
64, Pounds sterling 7.99 pbk

鈥楲earning at Teaching in School Science鈥� by D. Bentley and M. Watts,
Open University pp 202, Pounds sterling 9.95 pbk

鈥楾he National Curriculum: A Survival Guide for Parents鈥� by R. Merttens
and J. Vass, Octopus Publishing pp 32, Pounds sterling 1.99 pbk

HOW CAN a teacher help a group of 5-year-olds learn about science for
themselves? Here is one way: collect together lots of scraps of fabric,
wait for a rainy day, and say to the class, 鈥榃e need special clothes to
stay dry in the rain, don鈥檛 we? What sorts of fabric are good for keeping
us dry? I have lots of pieces of fabric here. Can you think of how we could
tell which ones would keep us dry?鈥� Once the children, with the teacher鈥檚
help, have worked out some good testing methods they can begin to experiment.

This is one of the suggestions in Developing Science in the Primary
Classroom. I don鈥檛 believe I have a great aptitude for teaching, but reading
Wynne Harlen and Sheila Jelly鈥檚 book makes me feel that even I could help
a child to investigate productively. The process of teaching and learning
science seems so enjoyable it encourages a feeling of confidence.

The section on 鈥楬andling children鈥檚 questions鈥� is a must for teachers
who fear that their own lack of scientific knowledge will make their attempts
to teach the subject ineffective. The trick is to turn the question around
so that the child works to find the answer, or at least some relevant information.
A child who wants to know, for example, why she can sometimes see herself
in a window is encouraged to investigate what lighting conditions provide
the best reflected image.

The book also brings up some quite subtle points about the philosophy
of teaching science. For example, an important goal of science teaching,
say the authors, should be to develop scientific attitudes. The children
should come to respect evidence, be willing to change their ideas in the
light of evidence, and to review their procedures critically. I can think
of a few researchers who would have benefited from such an education.

Some primary teachers might find it difficult to introduce science topics
in their classroom in a way that sounds natural and will stimulate the children鈥檚
interest. One approach would be to find a story that introduces a scientific
theme. Argon and Xenon is a science teaching kit that consists of work cards,
pages for photocopying, teachers鈥� notes, and a huge colourful picture book
for the children to look at while the teacher reads a series of stories.
The notes contain the stories and explain the projects and scientific insight
which can arise from the stories.

Using stories is a good idea but the stories in Argon and Xenon do not
present an entirely accurate image of science. Argon and Xenon are lightbulbs
which come to life because a scientific Professor X. Plore, is tired of
talking to herself. The professor is female but otherwise fits the stereotype
of a mad scientist. In one of the stories another scientist who is 鈥榠nventing
a plant food to make tomatoes a lovely bright red colour鈥�, allows his cat
to eat some of the substance. The cat turns red and becomes magnetic.

Until some less fantastic stories are available it might be better if
teachers let the real world stimulate their children鈥檚 ideas. An Early Start
to Nature offers a great deal of inspiration. Roy Richards鈥檚 explanations
and excellent colour illustrations provide the instructions and information
for performing many investigations into the natural world. Some of these
can be carried out in the classroom and others on field trips. The key is,
of course, not to give the pupils the instructions, just guidance.

Children who began taking an active part in their science education
when they were in primary school may be well prepared to move on to more
complex investigative projects when they reach secondary school but the
students who have spent the first years of their education sitting passively
are more of a challenge to the secondary school teacher. Learning and Teaching
in School Science gives examples of techniques and projects teachers developed
to initiate active learning in students who expect to be told what to do.

Doing an experiment according to instructions in a book may be an activity,
but it is not active learning. One teacher turned a set experiment into
an active learning project by putting each instruction on a separate strip
of paper so that the students could not tell in what order they came. Groups
of students were given a set of instructions and told the purpose of the
experiment. They then had to work out between themselves in what order to
carry out the instructions.

Di Bentley and Mike Watts have assembled 28 case studies for the book,
illustrating different approaches to work. One class was set the task of
working out how a very shy girl who had just started menstruating could
discover for herself which type of sanitary protection would be best. Another
class was visited by two contemporaries of Galileo. The scientist had published
a full account of his heretical work and the visitors were wondering how
he should be punished. The class did their best to defend Galileo.

If you are the parent of a child attending a state school in England
and Wales, the awful time will come when you have to go to the school and
receive the assessment. Apart from the usual worry about discovering that
your offspring may not be a genius after all, there is the danger that you
won鈥檛 be able to understand what the teacher is talking about.

The National Curriculum: A Survival Guide for Parents gives an easy-to-follow
crash course in the subject and will probably help you to make a favourable
impression on your child鈥檚 teacher. You鈥檒l be able to talk intelligently
about profile components, standard assessment tasks, key stages, class attainment
levels and all the rest.

Ruth Merttens and Jeff Vass also explain some of the philosophy behind
the Education Reform Act and the rights and responsibilities it gives to
parents. Like the children, parents are now being encouraged to play a more
active part in education. A Pounds sterling 1.99 investment in this book
will help you to learn the rules of the game.

Lesley Newson writes scientific books for children.