Metal Detectors and Treasure Hunting

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The earth hides many treasures from its inhabitants. Sometimes precious material is buried deep in the earth’s crust, and can be detected with pretty sophisticated measurement systems only. However, small metal objects which are close to the surface may be located fairly easily using simple equipment. A day’s hunting on the beach, for example, using the present metal detector may yield some unexpected finds.

In our experience, metal detectors have always had a very special appeal to many nature lovers. That is not difficult to explain, because few things are more exciting than the question ‘is there a valuable object just below the earth’s surface?’. Many amateurs will, for example, not want to miss the opportunity to scan an area for lost coins, where a large crowd has gathered. Metal detectors are also used professionally. Mine fields, for example, are minutely examined for buried explosives with the aid of advanced detectors.

Obviously, the requirements for a metal detector are dependent on the application. Most hobbyists will not need a complex, costly and extremely sensitive detector. many times a simple detector is capable of locating metal objects which are buried up to 15 cm below the surface. That means that the instrument, despite its simplicity, is suitable for scanning a lawn, a gravel path or a beach for lost metal objects. Those of you who are keen on experimenting will find metal detectors very rewarding to try out.

Treasure Hunting

Basically, two effects from elementary physics are employed to detect metal objects buried in the soil.

Firstly, a metal object changes the self-inductance of a coil and, if applicable, the degree of coupling between two coils. The effect may be positive or negative. The property of the materials which plays an important role in these effects is called relative permeability (µr). A distinction is made between paramagnetic materials (µr > 1), diamagnetic materials (µr < 1) and ferromagnetic materials (µr >> 1). Although it is fairly difficult to tell exactly which material is being detected just on the basis of the µr property, it is definitely possible to tell apart ferromagnetic materials on the one hand from paramagnetic or diamagnetic materials, on the other.

The second effect employed in the detection of metal objects is based on eddy currents which are generated when a conductor is subject to a varying magnetic field. The level of the eddy currents is determined by the size and the shape of the conducting object, as well as by the resistivity of the material. Strong eddy currents may be induced in, say, a large sheet of metal, while they are much reduced if slots are cut in the same sheet. Finally, the level of the eddy currents is also determined by the position of the object in the magnetic field, and, as a result, by the number of field lines that cross the object. We also have to take into account the distance of the object to the search head which contains the detection coil, and the effect of the soil. All in all, it will be clear that it is virtually impossible to obtain a reliable material indication on the basis of just one detection method.

Basic Circuits

In practical circuits of metal detectors, you may come across three different types of detection technique. Each if these is briefly discussed below.

BFO (beat frequency oscillator). In this system, a signal with a variable frequency is mixed with another signal having a fixed frequency. The difference (or ‘beat’) frequency produced by the mixer is in the audible range. If the search head comes close to a metal object, the oscillator producing the variable frequency is de-tuned, resulting in a different tone which the user hears via a loudspeaker.

TR/IB (transmit-receive/induction balance). As indicated by the name, this method utilizes a transmitter as well as a receiver. If a metal object comes within the scan range of the search head, the degree of magnetic coupling between the inductors is modified. This change, in turn, produces a change in the oscillator output signal level. PI (pulse induction). In this system pulses are generated and transmitted. The intensity and the shape of the received pulses provide an indication about the presence of metal objects within the scan range.

Each of the three detection methods has its own advantages and disadvantages. The ideal metal detector would, therefore, have to be a combination of all three detection methods. Unfortunately, that would result in a fairly complex circuit.

Digital Compass

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In spite of the precision of the GPS (Global Positioning System), the simplest way to determine direction and location is still by a magnetic (mariner’s) compass or gyro compass. Nowadays there are also electronic compasses. These compasses have no magnetic needle, but a magnetic sensor that is based on the Hall effect. Such a sensor needs only a few components to show the directions north (N), north-east (NE), east (E), south-east (SE), south (S), south-west (SW), west (W), north-west (NW) on a compass card.

The Swiss firm Pewatron sells two kinds of compass sensor, both of which react with great sensitivity to the earth’s magnetic field. These sensors facilitate the construction of an electronic compass for various applications. However, the analogue type, with its very high resolution, requires a quite complex electronic circuit, whereas the digital type (as used in the present design) only needs a few standard components and a standard logic IC to construct a compass with 45° resolution. The direction is indicated by a number of LEDs built into the compass card. The digital sensor is primarily intended for a hand-held compass, which may also be used in a car, boat or light aircraft.

Not many people know how to handle a compass correctly. It is only when you have learnt to fly, sail a yacht across the sea, or have been on a ‘really wild’ holiday that you appreciate that the compass needle does not normally point to the north. This has several causes. First, the geographical (true) north and magnetic north are not at the same location. This means that the lines of force surrounding the earth magnet are not parallel to the geographical meridians. Moreover, lines of force do not flow in a constant direction from the south magnetic pole to the north magnetic pole. Their direction fluctuates considerably, and for this reason the magnetic meridian cannot be defined as ‘the arc of a great circle joining the north and south magnetic poles’. Instead, it is defined as ‘the direction that a compass needle will take up when under the influence of the earth’s magnetic field only’. The angle between the magnetic meridian and the true meridian at any place is called the magnetic variation or declination. The north magnetic pole is moving slowly all the time: it makes a circle round the true north pole once in about a thousand years. In Britain, the westerly declination is decreasing by about 10 minutes of arc annually. The foregoing makes it clear that the resulting error in compass reading is greater near the true north pole than at the equator.

Another cause of error is the earth’s magnetic field, which is the space around it occupied by its lines of force. Any freely suspended magnetic needle placed in this field will align itself with the lines of force of the field. The direction of this field is horizontal at the magnetic equator, but as you travel northwards, the lines of force begin to dip, until, in Britain, they are inclined at an angle of about 60° to the horizontal. In a modern magnetic compass, the magnetic needle is not allowed to dip. This is achieved by having more than one needle (usually four to eight) so arranged that their common centre of gravity is below the point of suspension of the compass card.

 

Best Science Books for 2010

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Welcome to our Best of 2010 top 10 books for Science. This is a list of most popular science books at Amazon published for the first time in 2010. Best Science Books is definitely a collection of titles that should be present in the library of everybody interested in science.Science continuously evolves and brings new answers to old questions. Best Science Books of 2010 is the latest answer to these questions.

1. The Immortal Life of Henrietta Lacks

From a single, abbreviated life grew a seemingly immortal line of cells that made some of the most crucial innovations in modern science possible. And from that same life, and those cells, Rebecca Skloot has fashioned in The Immortal Life of Henrietta Lacks a fascinating and moving story of medicine and family, of how life is sustained in laboratories and in memory. Henrietta Lacks was a mother of five in Baltimore, a poor African American migrant from the tobacco farms of Virginia, who died from a cruelly aggressive cancer at the age of 30 in 1951. A sample of her cancerous tissue, taken without her knowledge or consent, as was the custom then, turned out to provide one of the holy grails of mid-century biology: human cells that could survive–even thrive–in the lab. Known as HeLa cells, their stunning potency gave scientists a building block for countless breakthroughs, beginning with the cure for polio. Meanwhile, Henrietta’s family continued to live in poverty and frequently poor health, and their discovery decades later of her unknowing contribution–and her cells’ strange survival–left them full of pride, anger, and suspicion. For a decade, Skloot doggedly but compassionately gathered the threads of these stories, slowly gaining the trust of the family while helping them learn the truth about Henrietta, and with their aid she tells a rich and haunting story that asks the questions, Who owns our bodies? And who carries our memories?


2. Packing for Mars: The Curious Science of Life in the Void

With her wry humor and inextinguishable curiosity, Mary Roach has crafted her own quirky niche in the somewhat staid world of science writing, showing no fear (or shame) in the face of cadavers, ectoplasm, or sex. In Packing for Mars, Roach tackles the strange science of space travel, and the psychology, technology, and politics that go into sending a crew into orbit. Roach is unfailingly inquisitive (Why is it impolite for astronauts to float upside down during conversations? Just how smelly does a spacecraft get after a two week mission?), and she eagerly seeks out the stories that don’t make it onto NASA’s website–from SPCA-certified space suits for chimps, to the trial-and-error approach to crafting menus during the space program’s early years (when the chefs are former livestock veterinarians, taste isn’t high on the priority list). Packing for Mars is a book for grownups who still secretly dream of being astronauts, and Roach lives it up on their behalf–weightless in a C-9 aircraft, she just can’t resist the opportunity to go “Supermanning” around the cabin. Her zeal for discovery, combined with her love of the absurd, amazing, and stranger-than-fiction, make Packing for Mars an uproarious trip into the world of space travel.


3. The Emperor of All Maladies: A Biography of Cancer

“In 2010, about six hundred thousand Americans, and more than 7 million humans around the world, will die of cancer.” With this sobering statistic, physician and researcher Siddhartha Mukherjee begins his comprehensive and eloquent “biography” of one of the most virulent diseases of our time. An exhaustive account of cancer’s origins, The Emperor of All Maladies illustrates how modern treatments–multi-pronged chemotherapy, radiation, and surgery, as well as preventative care–came into existence thanks to a century’s worth of research, trials, and small, essential breakthroughs around the globe. While The Emperor of All Maladies is rich with the science and history behind the fight against cancer, it is also a meditation on illness, medical ethics, and the complex, intertwining lives of doctors and patients. Mukherjee’s profound compassion–for cancer patients, their families, as well as the oncologists who, all too often, can offer little hope–makes this book a very human history of an elusive and complicated disease.


4. The Disappearing Spoon: And Other True Tales of Madness, Love, and the History of the World from the Periodic Table of the Elements

Science magazine reporter Kean views the periodic table as one of the great achievements of humankind, “an anthropological marvel,” full of stories about our connection with the physical world. Funny, even chilling tales are associated with each element, and Kean relates many. The title refers to gallium (Ga, 31), which melts at 84ËšF, prompting a practical joke among “chemical cognoscenti”: shape gallium into spoons, “serve them with tea, and watch as your guests recoil when their Earl Grey eats their utensils.” Along with Dmitri Mendeleyev, the father of the periodic table, Kean is in his element as he presents a parade of entertaining anecdotes about scientists (mad and otherwise) while covering such topics as thallium (Tl, 81) poisoning, the invention of the silicon (Si, 14) transistor, and how the ruthenium (Ru, 44) fountain pen point made million for the Parker company. With a constant flow of fun facts bubbling to the surface, Kean writes with wit, flair, and authority in a debut that will delight even general readers. 10 b&w illus.


5. Quantum: Einstein, Bohr, and the Great Debate about the Nature of Reality

Starred Review. With vigor and elegance, Kumar describes the clash of titans that took place in the world of physics in the early 20th century, between physicists who did and those who did not believe in the quantum—the strange concept that we now know to be the underpinning of reality. The titans in Kumar’s account of the conflict are Albert Einstein and Niels Bohr. In 1900, Max Planck discovered that electromagnetic radiation and the energy of light are transmitted not in a continuous flow but in small packets called quanta (singular, quantum). Bohr applied the idea of quantum to electrons, leading to the development of quantum mechanics. Bohr’s theory explained experimental results that were inexplicable in classical theory. Einstein rejected Bohr’s theory overturning reality in dangerous but also thrilling ways. The clash culminated at the 1927 Solway conference. Kumar, founding editor of Prometheus and a consulting science editor for Wired UK, recounts this meaty, dense, exciting story, filled with vivid characters and sharp insights. With physics undergoing another revolution today, Kumar reminds us of a time when science turned the universe upside down. 16 pages of photos.


6. The Grand Design

How can we understand the world in which we find ourselves? Over twenty years ago I wrote A Brief History of Time, to try to explain where the universe came from, and where it is going. But that book left some important questions unanswered. Why is there a universe–why is there something rather than nothing? Why do we exist? Why are the laws of nature what they are? Did the universe need a designer and creator?It was Einstein’s dream to discover the grand design of the universe, a single theory that explains everything. However, physicists in Einstein’s day hadn’t made enough progress in understanding the forces of nature for that to be a realistic goal. And by the time I had begun writing A Brief History of Time, there were still several key advances that had not yet been made that would prevent us from fulfilling Einstein’s dream. But in recent years the development of M-theory, the top-down approach to cosmology, and new observations such as those made by satellites like NASA’s COBE and WMAP, have brought us closer than ever to that single theory, and to being able to answer those deepest of questions. And so Leonard Mlodinow and I set out to write a sequel to A Brief History of Time to attempt to answer the Ultimate Question of Life, the Universe and Everything. The result is The Grand Design, the product of our four-year effort.In The Grand Design we explain why, according to quantum theory, the cosmos does not have just a single existence, or history, but rather that every possible history of the universe exists simultaneously. We question the conventional concept of reality, posing instead a “model-dependent” theory of reality. We discuss how the laws of our particular universe are extraordinarily finely tuned so as to allow for our existence, and show why quantum theory predicts the multiverse–the idea that ours is just one of many universes that appeared spontaneously out of nothing, each with different laws of nature. And we assess M-Theory, an explanation of the laws governing the multiverse, and the only viable candidate for a complete “theory of everything.” As we promise in our opening chapter, unlike the answer to the Ultimate Question of Life given in the Hitchhiker’s Guide to the Galaxy, the answer we provide in The Grand Design is not, simply, “42.”


7. The Mind’s Eye

In The Mind’s Eye, Oliver Sacks tells the stories of people who are able to navigate the world and communicate with others despite losing what many of us consider indispensable senses and abilities: the power of speech, the capacity to recognize faces, the sense of three-dimensional space, the ability to read, the sense of sight. For all of these people, the challenge is to adapt to a radically new way of being in the world.There is Lilian, a concert pianist who becomes unable to read music and is eventually unable even to recognize everyday objects, and Sue, a neurobiologist who has never seen in three dimensions, until she suddenly acquires stereoscopic vision in her fifties.There is Pat, who reinvents herself as a loving grandmother and active member of her community, despite the fact that she has aphasia and cannot utter a sentence, and Howard, a prolific novelist who must find a way to continue his life as a writer even after a stroke destroys his ability to read.And there is Dr. Sacks himself, who tells the story of his own eye cancer and the bizarre and disconcerting effects of losing vision to one side.Sacks explores some very strange paradoxes—people who can see perfectly well but cannot recognize their own children, and blind people who become hyper-visual or who navigate by “tongue vision.” He also considers more fundamental questions: How do we see? How do we think? How important is internal imagery—or vision, for that matter? Why is it that, although writing is only five thousand years old, humans have a universal, seemingly innate, potential for reading?The Mind’s Eye is a testament to the complexity of vision and the brain and to the power of creativity and adaptation. And it provides a whole new perspective on the power of language and communication, as we try to imagine what it is to see with another person’s eyes, or another person’s mind.


8. The Evolution of Childhood: Relationships, Emotion, Mind

This book is an intellectual tour de force: a comprehensive Darwinian interpretation of human development. Looking at the entire range of human evolutionary history, Melvin Konner tells the compelling and complex story of how cross-cultural and universal characteristics of our growth from infancy to adolescence became rooted in genetically inherited characteristics of the human brain.All study of our evolution starts with one simple truth: human beings take an extraordinarily long time to grow up. What does this extended period of dependency have to do with human brain growth and social interactions? And why is play a sign of cognitive complexity, and a spur for cultural evolution? As Konner explores these questions, and topics ranging from bipedal walking to incest taboos, he firmly lays the foundations of psychology in biology.As his book eloquently explains, human learning and the greatest human intellectual accomplishments are rooted in our inherited capacity for attachments to each other. In our love of those we learn from, we find our way as individuals and as a species. Never before has this intersection of the biology and psychology of childhood been so brilliantly described.”Nothing in biology makes sense except in the light of evolution,” wrote Dobzhansky. In this remarkable book, Melvin Konner shows that nothing in childhood makes sense except in the light of evolution.


9. Long for This World: The Strange Science of Immortality

With the bookshelves full of deathless vampires these days, it’s refreshing to read about immortality in the real world for a change. In Long for This World, Jonathan Weiner, who won a Pulitzer Prize for The Beak of the Finch, has written an elegant, curious, and personal account of the modern scientific search for a Fountain of Youth. The search for immortality has long been seen as a fanciful, alchemic quest, and the study of aging a mere biological backwater, but recent advances in both evolutionary and molecular biology have made the prospect of finding a cure for our apparently inevitable deterioration seem tantalizingly reachable, at least to figures like Aubrey de Grey, the bearded, beer-drinking English researcher whose impossibly confident drive toward thousand-year life spans is at the center of Weiner’s tale. Is Weiner convinced? He’s appealingly skeptical, and clear enough in explaining the science to make us equally so: if aging is a disease, it’s at least as complicated to cure as cancer (and in fact would require us to cure cancer, along with everything else that hunts us down). But he presents the optimists’ case with verve and appreciation, making their quest to exceed our human limits into a wonderfully human story.


10. Here’s Looking at Euclid: A Surprising Excursion Through t
he Astonishing World of Math

Unlike in a traditional classroom setting, Bellos’s book aims to reintroduce readers into the world of math by wandering off the beaten algebraic path and investigating interesting topics. Bellos, a former international newspaper correspondent, jets off to exotic places to talk to people about mathematical concepts that catch his fancy. Readers learn the remarkable story of how Sudoku became an overnight international sensation only after its developer, a retired judge, worked for six years on a computer program to write the puzzles. In Japan he visits a club whose school-age members can almost instantaneously add up a string of three-digit numbers by visualizing an abacus in their heads. When in America, Bellos finds himself in Nevada, exploring Reno’s casino scene with a discussion of why some gamblers win, but most don’t. Adult math buffs will be familiar with most of Bellos’s discoveries, but his enthusiasm and lively writing-along with helpful charts and graphics-should inspire younger readers to make their own journeys of mathematical exploration.You can also check the list of Best Science Books in 2009.

Best Science Books for 2009

Written by admin on . Posted in Book Reviews, Science and Technology

Welcome to our Best of 2009 top 10 lists for Science. Our list of the best science books of 2009  includes top pick, The Age of Wonder, Richard Holmes’s delightfully masterful group biography of the adventurous scientists of Britain’s Romantic age, Remarkable Creatures: Epic Adventures in the Search for the Origin of Species, Complexity: A Guided Tour and other top science books.Best Science Books are ranked according to Amazon’s customer orders through October. Only books published for the first time in 2009 are eligible. See more editors’ picks and customers’ favorites in our Best Books of 2009 Store.


1. The Age of Wonder: How the Romantic Generation Discovered the Beauty and Terror of Science

Amazon.com Review

Oliver Sacks is the author of Musicophilia, Awakenings, The Man Who Mistook His Wife for a Hat, and many other books, for which he has received numerous awards, including the Hawthornden Prize, a Polk Award, and a Guggenheim Fellowship. He is a member of the American Academy of Arts and Letters and lives in New York City, where he is a practicing neurologist. Read his exclusive guest review of The Age of Wonder: I am a Richard Holmes addict. He is an incomparable biographer, but in The Age of Wonder, he rises to new heights and becomes the biographer not of a single figure, but of an entire unique period, when artist and scientist could share common aims and ambitions and a common language–and together create a “romantic,” humanist science. We are once again on the brink of such an age, when science and art will come together in new and powerful ways. For this we could have no better model than the lives of William and Caroline Herschel and Humphry Davy, whose dedication and scientific inventiveness were combined with a deep sense of wonder and poetry in the universe. Only Holmes, who is so deeply versed in the people and culture of eighteenth-century science, could tell their story with such verve and resonance for our own time.


2. Remarkable Creatures: Epic Adventures in the Search for the Origin of Species

It’s unclear whether the title refers to the daring naturalist/explorers Carroll depicts or the creatures whose remains they found. In this thoroughly enjoyable book, Carroll (Endless Forms Most Beautiful), a molecular biologist at the University of Wisconsin, provides vignettes of some of the fascinating people who have made the most significant discoveries in evolutionary biology. He starts with some of the experiences and insights of great explorers like Alexander von Humboldt, Charles Darwin, Alfred Russel Wallace and Henry Walter Bates, then turns his attention to paleontologists who searched for the fossil evidence to support the new theory of evolution. Among them are Euge`ne Dubois’s discovery of Java Man; Charles Walcott’s discovery of the Burgess Shale and the evidence it provided for the Cambrian explosion; and Neil Shubin’s recent discovery in arctic Canada of Tiktaalik, the intermediary between water- and land-dwelling vertebrates. Carroll closes with studies of human evolution, from Louis and Mary Leakey to the advances of Linus Pauling and Allan Wilson, which indicated that Neanderthals were cousins of Homo sapiens rather than direct ancestors. While there’s little that’s new here, Carroll does weave an arresting tapestry of evolutionary advancement.


3. Complexity: A Guided Tour

“All theoretical models are wrong, but some are useful.” Both inevitable error and promising usefulness abound in the bold conceptual models that Mitchell surveys in exploring the nascent science of complexity. Readers will marvel at the sheer range of settings in which complex systems operate: from ant hills to the stock market, from T cells to Web searches, from disease epidemics to power outages, complexity challenges theorists’ intellectual adroitness. With refreshing clarity, Mitchell invites nonspecialists to share in these researchers’ adventures in recognizing and measuring complexity and then predicting its cascading effects. Concepts central to thermodynamics, information theory, and computer programming all come into focus in this foray into the recesses of complexity. Still, the analysis illuminates more than explanatory frameworks (such as network diagrams and genetic algorithms); piquant personalities (including Stephen Jay Gould and John von Neumann) also receive illuminating scrutiny. Though Mitchell acknowledges the doubts of skeptics, she still expresses hope that persistent complexity researchers will yet weld their disparate accomplishments into a coherent paradigm. Mind-expanding.


4. Fixing My Gaze: A Scientist’s Journey Into Seeing in Three Dimensions

“Fixing My Gaze is a beautiful description and appreciation of two very distinct ways of seeing… But it is also an exploration of much more. Sue is at pains not only to present her story, in clear and lucid, often poetic, language, but also, as a scientist, to provide understanding and explanation. She is in a unique position to do this, drawing on both her personal experience and her background as a neurobiologist….Though Sue originally thought her own case unique, she has since found a number of other people with strabismus and related problems who have unexpectedly achieved stereo vision through vision therapy. This is no easy accomplishment. It may require not only optical corrections (proper lenses or prisms, for example), but very intensive training and learning–in effect, learning how to align the eyes and to fuse their images, and unlearning the unconscious habit of suppressing vision which has been occurring perhaps for decades. In this way, vision therapy is directed at the whole person: it requires high motivation and self-awareness, and enormous perseverance, practice and determination, as does psychotherapy, for instance, or learning to play the piano. But it is also highly rewarding, as Sue brings out. And this ability to acquire new perceptual abilities later in life has great implications for anyone interested in neuroscience or rehabilitation, and, of course, for the millions of people who, like Sue, have been strabismic since infancy.Sue’s case, and many others, suggest that if there are even small islands of function in the visual cortex, there may be a fair chance of reactivating and expanding them in later life, even after a lapse of decades, if vision can be made optically possible. Cases like these may offer new hope for those once considered incorrigibly stereo-blind. Fixing My Gaze will offer inspiration for anyone in this situation, but it is equally a very remarkable exploration of the brain’s ability to change and adapt, and an ode to the fascination and wonder of the visual world, even those parts of it which many of us take for granted.”


5.The Strangest Man: The Hidden Life of Paul Dirac, Mystic of the Atom

Paul Dirac (1902 – 1984) shared the Nobel Prize for physics with Erwin Schrödinger in 1933, but whereas physicists regard Dirac as one of the giants of the 20th century, he isn’t as well known outside the profession. This may be due to the lack of humorous quips attributed to Dirac, as compared with an Einstein or a Feynman. If he spoke at all, it was with one-word answers that made Calvin Coolidge look loquacious . Dirac adhered to Keats’s admonition that Beauty is truth, truth beauty: if an equation was beautiful, it was probably correct, and vice versa. His most famous equation predicted the positron (now used in PET scans), which is the antiparticle of the electron, and antimatter in general. In 1955, Dirac came up with a primitive version of string theory, which today is the rock star branch of physics. Physicist Farmelo (It Must Be Beautiful) speculates that Dirac suffered from undiagnosed autism because his character quirks resembled autism’s symptoms. Farmelo proves himself a wizard at explaining the arcane aspects of particle physics. His great affection for his odd but brilliant subject shows on every page, giving Dirac the biography any great scientist deserves.


6. Every Patient Tells a Story

In her first book, internist and New York Times columnist Sanders discusses how doctors deal with diagnostic dilemmas. Unlike Berton Roueché in his books of medical puzzles, Sanders not only collects difficult cases, she reflects on what each means for both patient and struggling physician. A man arrives at the hospital, delirious, his kidneys failing. Batteries of tests are unrevealing, but he quickly recovers after a resident extracts two quarts of urine. An abdominal exam would have detected the patient’s obstructed, grossly swollen bladder. The author then ponders the neglect of the physical exam, by today’s physicians, enamored with high-tech tests that sometimes reveal less than a simple exam. Another patient, frustrated at her doctor’s failure to diagnose her fever and rash, googles her symptoms and finds the correct answer. Sanders uses this case to explain how computers can help in diagnoses (Google is not bad, she says, but better programs exist). Readers who enjoy dramatic stories of doctors fighting disease will get their fill, and they will also encounter thoughtful essays on how doctors think and go about their work, and how they might do it better.


7. The Mathematical Mechanic: Using Physical Reasoning to Solve Problems

Mark Levi’s book “The Mathematical Mechanic” is a wonderful attempt to integrate physical reasoning with mathematical reasoning. These two strands have historically run in parallel and only occasionally have they been united at least at a pedagogical level. There seems to be a trend among Russian mathematicians particularly in the area of differential equations whereby they use physical reasoning to illuminate the more abstract mathematical approaches that are taken. V I Arnold is an example someone who has been known to integrate the two approaches. Perhaps Levi’s Russian roots explain some of the impetus for this book. As mathematics becomes more and more specialized I fear that fewer mathematicians have the time or even inclination to think about the interconnections between physical reasoning and their own area. Levi’s book is an antidote to that trend and he is to be congratulated for his efforts.What Levy does is to take a large number of mathematical problems/theorems and show how physical reasoning using concepts such as conservation of energy, torque, resolution of forces, etc can be used to solve what are quite fundamental problems/theorems. In Chapter 2 he uses essentially torque concepts to prove the Pythagorean theorem be a thought experiment involving a right angled prism sitting in a water filled fish tank but attached to a spindle so it can rotate. The fact that it doesn’t (ie there is zero net torque) leads directly to Pythagoras’ Theorem.


8. Truth, Lies, and O-Rings: Inside the Space Shuttle Challenger Disaster

On a cold January morning in 1986, NASA launched the Space Shuttle Challenger, despite warnings against doing so by many individuals, including Allan McDonald. The fiery destruction of Challenger on live television moments after launch remains an indelible image in the nation’s collective memory. In “Truth, Lies, and O-Rings”, McDonald, a skilled engineer and executive, relives the tragedy from where he stood at Launch Control Center. As he fought to draw attention to the real reasons behind the disaster, he was the only one targeted for retribution by both NASA and his employer, Morton Thiokol, Inc., makers of the shuttle’s solid rocket boosters. In this whistle-blowing yet rigorous and fair-minded book, McDonald, with the assistance of internationally distinguished aerospace historian James R. Hansen, addresses all of the factors that led to the accident, some of which were never included in NASA’s “Failure Team” report submitted to the Presidential Commission. “Truth, Lies, and O-Rings” is the first look at the Challenger tragedy and its aftermath from someone who was on the inside, recognized the potential disaster, and tried to prevent it. It also addresses the early warnings of very severe debris issues from the first two post-Challenger flights, which ultimately resulted in the loss of Columbia some fifteen years later. What they didn’t want you to know.


9. Dissection: Photographs of a Rite of Passage in American Medicine 1880-1930

This is a startling window into the education of American doctors in the late 19th and early 20th centuries-on both a visceral level and for its revealing cultural record. Cringe-worthy shots of medical students-bare-handed gentlemen and a few ladies in street clothes show off their scalpels, saws and textbooks-while their cadavers, mostly poor and black, are awkwardly posed, and exposed. In one stunning shot, a black woman looks out from behind the young students. “What are we to make of an African-American woman, standing, broom handle in hand, behind the dissection table, her gaze fixed on the camera?” the authors ask. More importantly, they conclude, the photo is now drawn “out of the shadows of history” where “we can at least bear witness.” A blood-soaked dissection table makes you want to look away and the dark humor of students playing pranks with skeletons are both hilarious and horrible. Postcards sent to family and friends must have caused shock and awe for postmen and recipient alike. Here, a difficult glanc
e into medicine’s “uncomfortable past” offers a grand opportunity to understand the legacy doctors and patients live with, and benefit from, today.


10. The Monty Hall Problem: The Remarkable Story of Math’s Most Contentious Brain Teaser

Mathematicians call it the Monty Hall Problem, and it is one of the most interesting mathematical brain teasers of recent times. Imagine that you face three doors, behind one of which is a prize. You choose one but do not open it. The host–call him Monty Hall–opens a different door, always choosing one he knows to be empty. Left with two doors, will you do better by sticking with your first choice, or by switching to the other remaining door? In this light-hearted yet ultimately serious book, Jason Rosenhouse explores the history of this fascinating puzzle. Using a minimum of mathematics (and none at all for much of the book), he shows how the problem has fascinated philosophers, psychologists, and many others, and examines the many variations that have appeared over the years. As Rosenhouse demonstrates, the Monty Hall Problem illuminates fundamental mathematical issues and has abiding philosophical implications. Perhaps most important, he writes, the problem opens a window on our cognitive difficulties in reasoning about uncertainty.You can also check the list of Best Science Books in 2010.