Cover; April 2002; Scientific American Magazine; by Staff Editor; 1 Page(s)

Table of Contents; April 2002; Scientific American Magazine; by Staff Editor; 2 Page(s)

SA Perspectives: The Peculiar Institution; April 2002; Scientific American Magazine; by Staff Editor; 1 Page(s)

Most Americans probably assume that slavery ended in 1865. Unfortunately, they are wrong. Potentially millions of people around the world still live and toil in involuntary servitude: Slavic women in European brothels, bonded laborers in South Asia, cocoa plantation workers in West Africa. Their plight has drawn occasional attention from newspapers and magazines. But does discussion of it belong in a science magazine? The editors have been debating this question since we began to consider an article on the topic a year and a half ago. Ultimately we decided that the answer is yes [see "The Social Psychology of Modern Slavery," on page 80].

Whenever we run articles on social topics, some readers protest that we should stick to "real" science. A number also claim that the magazine has become "more politicized" in recent years. We understand: the social sciences lack the precision of the physical or biological sciences, and they are more likely to have political implications.

How to Contact Us; April 2002; Scientific American Magazine; by Staff Editor; 1 Page(s)

Letters to the Editors; April 2002; Scientific American Magazine; by Staff Editor; 2 Page(s)

"In 'Evaluating the Threat' [News Scan, December 2001], Ed Regis confuses the threat of biological weapons to public health with their threat to national security," writes C. Allen Black of the University of Pittsburgh. "The fact that bioweapons are not likely to be used for mass destruction is of no comfort or even practical relevance when our government and the entire U.S. infrastructure is vulnerable to one or a few men that the police and government seem powerless to find or stop. Perhaps after the anthrax attack, there is no justification for mass vaccinations based on the public health threat. From now on, though, an oath of office should be preceded by vaccination."

Below, readers respond to this and other topics from the December 2001 issue.

50, 100 and 150 Million Years Ago; April 2002; Scientific American Magazine; by Staff Editor; 1 Page(s)

HUGE SHOES FOR SALE-"Standing at the podium, Lionel B. Ambulocetus, the president of the International League of Whales, was brief in his remarks, but there was no mistaking his anger. 'That's it, we're getting out of here,' he proclaimed. 'Life on land has no future, so we're returning to the seas. I've urged all our members to begin spending more time at the beach and to look for mates with shorter legs. We know it's not going to happen overnight, but we're going back to the oceans where we belong.' Staring down at his own feet, he said, 'A day will come when I need these like a hole in the head.'

"Mr. Ambulocetus was not shy about explaining the reasons for the whales' planned migration. 'Quite frankly, it's the primates. I know they're small and there aren't very many of them, but they make an unbelievable amount of noise, and their little grasping forefeet give me the creeps. We are convinced that the primates are going to cause a lot of trouble for everyone, and we don't want to be around when it happens. At least in the oceans, we'll be safe.'"

50, 100 and 150 Years Ago; April 2002; Scientific American Magazine; by Staff Editor; 1 Page(s)

THE ANTIBIOTIC ERA-"Although more than 300 antibiotic substances have now been discovered, only five (penicillin, streptomycin, chloromycetin, aureomycin and terramycin) have attained the stature of major drugs. A handful of others have important, though limited, uses or are considered promising. All the rest have fallen short for one reason or another. Some are too weak; some work only in the test tube or on subhuman animals; most are too toxic. Naturally the search for potential new 'wonder' drugs goes on with undiminished fervor. The field for searching is very wide. There is hardly an area in the plant kingdom that has not yielded antibiotic substances: they have come from seed plants, lichen, many groups of fungi, the actinomycetes and bacteria."

FRESH FOOD IN WINTER-"Science has deliberately set at defiance of all the laws which govern the seasons of growth, and in the conflict it has proved a great triumph for man. Winter gardening and farming in the southern belt of States where the climate is warm enough to produce out of doors have spread with phenomenal rapidity in recent years. Our whole system of living and diet have been transformed by this industry, and our winter season is supplied with fruits and vegetables almost as freely as the summer. The expansion has been due to the railroads and steamship companies operating lines along the coast or through the belt of southern States. There are some 60,000 refrigerator cars engaged in this traffic in the winter season."

Has the Space Age Stalled?; April 2002; Scientific American Magazine; by Mark Alpert; 2 Page(s)

Two abandoned spacecraft are hidden in California's Mojave Desert, and they're not crashed UFOs. These relics were built by hopeful human engineers. Inside a storage building at Edwards Air Force Base is the partially assembled X-33, a prototype space plane conceived by NASA and Lockheed Martin. About 20 miles away, in a building at Mojave Airport, is the Roton, a six-story-tall test vehicle constructed by the now defunct Rotary Rocket Company. Just a few years ago these machines were hailed as the forerunners of a revolutionary new generation of reusable launch vehicles. But these days they're merely sad reminders of a dream unfulfilled.

The dream is a cheap, reliable way to carry people and payloads into orbit. The space shuttle falls far short of that goal: each flight costs about $500 million. The X-33 program was intended to produce a more cost-effective, fully reusable craft that could reach orbit with just one rocket stage. (The shuttle, in contrast, is a two-stage vehicle that jettisons a pair of solid-fuel boosters during its ascent to lessen the mass lifted into space.) But such a craft would have to carry 10 times its weight in fuel, and the technologies needed to reach that goal-such as the use of lightweight composite materials for fuel tanks-proved more troublesome than expected. After five years of effort, NASA canceled the program last year (the total cost: $912 million for NASA, $357 million for Lockheed). Several months later the U.S. Air Force turned down a chance to finish assembling the X-33 but agreed to store the vehicle's parts to save them from the scrap heap.

Looking at ART; April 2002; Scientific American Magazine; by Tabitha M. Powledge; 2 Page(s)

When a National Academy of Sciences study group in January called for outlawing the creation of babies via cloning, the world's media took notice, and so did the U.S. Senate, where a few days later the NAS report formed the centerpiece of a hearing. Largely ignored, however, was a recommendation in the report that could have much wider impact. The NAS panel concluded that it's time to consider imposing more regulations on the field of assisted reproduction.

Assisted reproductive technology (ART) exploded into public consciousness in 1978 with the birth of Louise Brown, the first successful product of in vitro fertilization. In IVF, sperm and egg are mated in a lab dish, and a few days later the resulting embryo is transferred into a woman's carefully prepared uterus. IVF accounts for most ART business, but lately other procedures have emerged, among them intracytoplasmic sperm injection, in which sperm is inserted directly into an egg, and preimplantation genetic diagnosis, in which an embryo is vetted for genetic defects before transfer into a waiting womb.

Heads on Tails; April 2002; Scientific American Magazine; by Phil Scott; 2 Page(s)

The November 12 crash of Flight 587 in New York City, in which the tail fin, or vertical stabilizer, of an Airbus A300 fell off, raised concerns about the increasing use of composites over metal. Composites consist of layers of carbon-fiber sheets impregnated with resin, making them lighter and stronger than the traditional aluminum. Preliminary crash reports from the National Transportation Safety Board indicate that composite layers on the Airbus had come apart, or delaminated, near the point where the stabilizer attaches to the aircraft body. When pilots attempted to maneuver with the tail's rudder in the wake turbulence from a preceding aircraft, the entire vertical stabilizer separated from the airplane, sending the A300 into a death spiral.

Aviation experts found the falling tail fin extremely strange. Unlike metal, composites don't "fatigue" with use-assuming no construction flaws, they remain as good as new over the years as long as the structure doesn't encounter forces greater than its design limit. The Airbus tail was made to withstand 50 percent more force than is typically encountered, although in February NTSB officials concluded that sudden back-and-forth movements of the rudder could damage the tail. Crash investigators now plan to use technologies for "nondestructive evaluation" to conduct a postmortem on the tail, in the hopes of determining whether the breakage stemmed from undetected, preexisting damage or whether composites contain some inherent flaw.

Mind the Gap; April 2002; Scientific American Magazine; by Sergio Pistoi; 1 Page(s)

Science is growing faster in the European Union than in the U.S., according to recent findings by the European Commission. The report, issued as a first step toward a systematic benchmarking of European research, consists of a collection of 15 indicators related to human resources, investment and scientific productivity measured in terms of the number of scientific publications-specifically, articles, notes, reviews and letters. Whereas the number of publications in the E.U. is steadily increasing, the rate is declining in the U.S. The average annual growth has risen, on average, by 3 percent from 1995 to 1999 in the E.U., while it has essentially flatlined in the U.S. Citations for these papers (a proxy for measuring their impact) also lessened in the U.S. In 1996, the last year for which these data are available, citations were higher in the E.U. for all research fields.

"We now see that the gap is widening" in terms of the citations and the number of publications, affirms Yvan Capouet, a member of the E.U. research commissioner's cabinet. Rolf F. Lehming, program director of the division of science resources statistics at the National Science Foundation, concurs: "There has been a decline in U.S. number of publications since 1995, following years of almost linear growth."

Drink Your Shots; April 2002; Scientific American Magazine; by Brenda Goodman; 1 Page(s)

For one out of five unlucky souls in the U.S., there's no mistaking the red, swollen eyes, drippy nose, sore throat and angry, inflamed nasal passages. The average person battles the scourge of allergy season with a small arsenal of pills, drops and inhalers, to the tune of $120 a year. And that's merely to stifle symptoms. Worse yet, such treatments won't stop about 20 percent of cases of allergic rhinitis from progressing to full-blown asthma-a condition that, despite improvements in drug therapies, now kills twice as many people in the U.S. every year as it did in 1980.

One weapon to tame the overreacting immune system is immunotherapy-gradual delivery of the substances that trigger allergies to acclimate the body to the world around it. In children it has been proved to prevent the development of new allergies and even asthma. For adults it can reduce the sneezing and wheezing of rhinitis by 80 percent and reduce the need for medications by an impressive 88 percent. This approach, however, requires the patient to assume the role of pincushion-doses must be delivered via a large needle twice weekly for the first few months and then monthly for up to five years. That's a total of at least 100 shots. No wonder the American College of Allergy, Asthma and Immunology found immunotherapy to be seriously underused.

Joke Hunter of Science; April 2002; Scientific American Magazine; by Steve Nadis; 1 Page(s)

When April Fools' Day rolls around, many people look for little jokes to play on their friends. Marc Abrahams casts his net far wider, searching for the biggest jokes in the science world. April is when planning for the Ig Nobel prize ceremony "kicks into high gear," Abrahams explains. He has much to do before the event is held this October at Harvard University. In addition to settling on a list of winners, he'll write the libretto for a mini opera on jargon that will premiere at the prize ceremony, finish a book on the event's illustrious heritage, and continue to edit and publish the science humor magazine the Annals of Improbable Research, or AIR.

His other activities include leading an international campaign to prevent the desecration of the plastic pink flamingo (invented by former Ig winner Don Featherstone), boosting membership in the Luxuriant Flowing Hair Club for Scientists (a group founded in honor of the Massachusetts Institute of Technology's Steven Pinker) and reviewing lunchrooms at various research hot spots for AIR. Such is the improbable life of one of science humor's most visible champions and possibly the only person in the world to pursue this line of work full-time.

By the Numbers: Greenhouse Follies; April 2002; Scientific American Magazine; by Rodger Doyle; 1 Page(s)

A quick and sure way to slow global warming is to arrange a really deep depression like the one that occurred in eastern Europe after the breakup of the Soviet empire. As the bottom left chart shows, such disintegration resulted in a steep decline in carbon dioxide emissions in that region. This episode illustrates that prosperity is a driving force behind the growing level of greenhouse gases. As incomes rise, people increasingly spend their money on autos, air-conditioning and other energy-intensive technologies, thus contributing to global warming.

Rising population is another prime contributor. Had population not changed since 1950, carbon emissions would now be 40 percent of their current level. Of course, the world community will not be reducing the population or striving to cap prosperity. Instead it has focused on getting international agreements to lower emissions. The latest effort in this direction, the Kyoto Protocol, would set legally binding national targets for emission reductions. The Kyoto process, however, is in trouble, because not all countries (notably, the U.S.) will ratify it. Other efforts-such as the U.S. movement to impose higher mileage standards on sport-utility vehicles and the European Union plan to levy a tax on energy-have floundered.

News Scan Briefs; April 2002; Scientific American Magazine; by Philip Yam, Alison McCook, JR Minkel; 2 Page(s)

In No Uncertain Terms: The Bohr family has finally released the mysterious letters that Niels Bohr wrote but never sent to Werner Heisenberg. They shed some light on the two physicists' mysterious meeting in 1941, which became the basis for Michael Frayn's play Copenhagen. In the letters, released in February, Bohr indicates that Heisenberg was not in fact stalling the Nazi atomic bomb program, as Heisenberg later claimed. "You spoke in a manner that could only give me the firm impression that, under your leadership, everything was being done in Germany to develop atomic weapons," Bohr wrote. The documents are not likely to be the last word, as some historians think Bohr could have misinterpreted Heisenberg's statements.-Philip Yam

Gene Fiends?: As genetically modified crops in North America grow, so does the debate over their use. A January report commissioned by the British conservation group English Nature showed that in Canada neighboring canola crops modified to be resistant to different kinds of herbicides have cross-pollinated and produced seeds that contain multiple resistances. If left behind after a harvest, the seeds could grow amid new crops or in field margins; English Nature argues that the offspring could become noxious weeds uncontrollable by existing chemicals. Keith Downey, research scientist emeritus at Canada's Saskatoon Research Center, disagrees. Canadian researchers expected resistance genes to accumulate, he says, and because there are more herbicides than resistance genes, the plants are just as easy to control as singly modified varieties. "The presence of the additional gene doesn't change it one little bit," Downey contends.

Innovations: It's Not Easy Being Green; April 2002; Scientific American Magazine; by Steven Ashley; 2 Page(s)

Larry Koskan's moment of inspiration arrived in the mid-1980s, when the organic chemist read a report by marine biologists at Clemson University and the University of South Alabama describing how oyster shells grow. Scientists knew that the mollusks secrete calcium carbonate as the essential constituent of their hardened exteriors. But what was new was the discovery that oysters also produce special protein-based agents that mold the mineral into their shells' characteristic shape. "When I realized that very low doses of the biopolymer they'd found-polyaspartate-inhibit the formation of calcium carbonate, the hair on the back of my neck rose up," Koskan recalls.

At the time, Koskan was employed by Nalco Chemical Company, where he was studying the properties of water-soluble polyacrylates (polyacrylics). Among other things, these widely used polymer additives help to stem the buildup of damaging mineral scale deposits (carbonate and sulfate compounds) on the surfaces of industrial water-treatment equipment. He realized that biodegradable polyaspartate could do the same job.

Staking Claims: Tragedy of the Cyber Commons; April 2002; Scientific American Magazine; by Gary Stix; 1 Page(s)

Digital technology-of which the Internet is the most noteworthy exemplar-has enabled an extraordinary flourishing of creativity: people graduate from being passive consumers of music, video and other content to becoming publishers of their own works. Lawrence Lessig, a professor at Stanford Law School, suggests that the neutral platform, or commons, on which this newfound freedom thrives faces a mortal threat from entrenched telecommunications, cable and media interests. Lessig, who articulates these arguments in his recent book, The Future of Ideas: The Fate of the Commons in a Connected World, talked with Scientific American's Gary Stix about what lies ahead.

Describe the notion of a commons in relation to the Internet and how it might be endangered. The Internet until now has been designed so that the network owner is not in a position to exercise control over the content or applications that run on it. The right to innovate is therefore held in common among all people who use the network and cannot be checked by the network owner. This freedom is increasingly under threat. The danger is that one class of property owners will use the legal system to veto certain kinds of innovation that no longer accord with its business interests. These owners will have the power to choose what kind of innovation is permitted-and that's inconsistent with the innovation commons.

Skeptic: Skepticism as a Virtue; April 2002; Scientific American Magazine; by Michael Shermer; 1 Page(s)

Poets often express deep insights into human nature with far less verbiage than scientists. Alexander Pope's Essay on Man, for example, is filled with pithy observations on the dualistic tensions of the human condition: Placed on this isthmus of a middle state, A Being darkly wise, and rudely great: With too much knowledge for the Sceptic side, With too much weakness for the Stoic's pride, He hangs between; in doubt to act, or rest, In doubt to deem himself a God, or Beast, In doubt his mind or body to prefer; Born but to die, and reasoning but to err.

Pope has packed a lot into this refrain, but the final clause is an important challenge to science: Is all our reasoning for naught, to end only in error? Such fear haunts us in our quest for understanding, and it is precisely why skepticism is a virtue. We must always be on guard against errors in our reasoning. Eternal vigilance is the watchword not just of freedom but of thought. That is the very nature of skepticism.

Profile: Father of the Impossible Children; April 2002; Scientific American Magazine; by Sergio Pistoi; 2 Page(s)

A few hundred yards away from the Vatican, a fertility clinic has become both the top destination for desperate couples and the pope's most troublesome neighbor. As clients enter, they are greeted in the narrow corridor by a huge portrait of a pregnant Madonna. The towering image is an auspicious sign for the half a dozen couples who eagerly wait their turn for a consultation. As they sit, a man in a green surgical suit rushes from room to room, often yelling in a raspy voice on his mobile phone. His harried assistant witnesses the scene with dismay. "I'm going to die. I swear I'm going to die," she mutters.

The taskmaster in the scrubs is Severino Antinori, a physician whose reputation among infertile couples is far overshadowed by his international fame as the man who wants to clone a human being. Antinori's unapologetic stance has provoked worldwide condemnation that reached its crescendo last summer, when an eminent representative of the Catholic Church compared him to Adolf Hitler.

Proteins Rule; April 2002; Scientific American Magazine; by Carol Ezzell; 8 Page(s)

Move over, human genome, your day in the spotlight is coming to a close. Researchers are now concentrating on the human proteome, the collective body of proteins made by a person's cells and tissues. The genome-the full set of genetic information in the body-contains only the recipes for making proteins; it's the proteins that constitute the bricks and mortar of cells and that do most of the work. And it's proteins that distinguish the various types of cells: although all cells have essentially the same genome, they can differ in which genes are active and thus in which proteins are made; likewise, diseased cells often produce proteins that healthy cells don't, and vice versa.

Accordingly, corporate and academic scientists are looking to catalogue all human proteins and uncover their interactions with one another. The goal is to devise better drugs with fewer side effects. Reaching that goal won't be a walk in the park, though: proteins are even more difficult to study than genes, and biotech companies are still struggling to come up with the best techniques and instruments for the task. Nevertheless, a race of sorts is on, with at least one company predicting that within three years it will have deciphered the human proteome, an important step in piecing together the myriad interactions among the individual proteins. Meanwhile federal programs are offering money to academic scientists to study the proteomes of cancer cells and serum, the watery component of human blood.

Augmented Reality: A New Way of Seeing; April 2002; Scientific American Magazine; by Steven K. Feiner; 8 Page(s)

If we extrapolate from current systems, it's easy to imagine a proliferation of high-resolution displays, ranging from tiny handheld or wrist-worn devices to large screens built into desks, walls and floors. Such displays will doubtless become commonplace. But I and many other computer scientists believe that a fundamentally different kind of user interface known as augmented reality will have a more profound effect on the way in which we develop and interact with future computers.

Augmented reality (AR) refers to computer displays that add virtual information to a user's sensory perceptions. Most AR research focuses on "see-through" devices, usually worn on the head, that overlay graphics and text on the user's view of his or her surroundings. (Virtual information can also be in other sensory forms, such as sound or touch, but this article will concentrate on visual enhancements.) AR systems track the position and orientation of the user's head so that the overlaid material can be aligned with the user's view of the world. Through this process, known as registration, graphics software can place a three-dimensional image of a teacup, for example, on top of a real saucer and keep the virtual cup fixed in that position as the user moves about the room. AR systems employ some of the same hardware technologies used in virtual-reality research, but there's a crucial difference: whereas virtual reality brashly aims to replace the real world, augmented reality respectfully supplements it.

Parasitic Sex Puppeteers; April 2002; Scientific American Magazine; by Laurence D. Hurst and James P. Randerson; 6 Page(s)

Don't bite the hand that feeds you. The old adage sums up the approach parasites are expected to take with their victims. A freeloader that can spread only when its host reproduces ought not to be overly harmful: too much damage to its unwilling benefactor will affect the parasite's own chances to procreate. This scheme contrasts with the tactics of a pathogen that has a short infectious period, such as the flu virus. In that case, the virus has no long-term interest in the carrier's well-being, so a "get transmitted quick" strategy is favored almost regardless of the cost to the hapless host.

The widely distributed bacterium Wolbachia (a close relative of the gut bacterium Escherichia coli) is a boarder with a long-term interest in its invertebrate host. It lives within cells and is transmitted to the next generation by invading its host's eggs. Contrary to the old saying, however, the bacterium engages in various radical manipulations of its hosts, including killing male offspring, turning males into females and rendering some host matings infertile. If Wolbachia's reproduction is so intimately tied up with that of its meal ticket, why does it create so much havoc?

Ripples in Spacetime; April 2002; Scientific American Magazine; by W. Wayt Gibbs; 10 Page(s)

HANFORD, WASH., AND LIVINGSTON, LA.-A chill January wind sends a shiver through Frederick J. Raab as he stands, binoculars to his eyes, on a mound near the center of the LIGO Hanford Observatory. He runs his gaze northward down a ruler-straight concrete tunnel to a building four kilometers to the north: there is one end of the observatory. Pivoting 90 degrees, Raab pans westward across the sagebrush-stubbled desert until he spots an identical tube and another building, also four kilometers distant. "When we talk about locking the laser beam" that shines inside those tubes, Raab says, "we mean holding the light waves steady to better than the width of an atom-over that distance."

Raab oversaw the construction of this giant try square, one of a pair that are the largest, most expensive and-if they fulfill the ambition of their designers-most sensitive detectors yet to join the 40-year hunt for gravitational waves. Part ruler, part clock, these two instruments are spacetime meters that will attempt to record how the continuum is rattled by the most violent cataclysms in the universe: detonating stars, colliding black holes, perhaps phenomena not yet imagined. As these ripples expand outward at the speed of light, they alternately stretch and squeeze space, causing the distance between free-floating objects to expand and contract. But by the time the vibrations reach the earth, theorists estimate, they are so unsubstantial that they alter distances by less than one part in a trillion billion.

The Science of Bad Breath; April 2002; Scientific American Magazine; by Mel Rosenberg; 8 Page(s)

Consider the case of Dr. John Floss. A dedicated dentist, Dr. Floss works long hours, often so focused on his patients that he neglects to eat or drink. His own teeth and gums are, of course, exemplary. Nevertheless, Dr. Floss is unaware of a problem emanating from his mouth. His patients know, as does his hygienist. But they are too embarrassed to inform Dr. Floss: he has exceedingly bad breath.

In this bad-breath scenario, as in many, the foul odor is the result of the metabolic activity of oral bacteria that are happily feeding on a small pool of postnasal drip that regularly collects on the back of the dentist's tongue. The bacteria leave behind a collection of rank compounds. Gargling with an effective mouthwash and cleaning the tongue would most likely alleviate the problem. Even chewing a few bites of food would help. For now, though, the dentist's patients are protected only by his surgical mask.

The Social Psychology of Modern Slavery; April 2002; Scientific American Magazine; by Kevin Bales, sidebar by George Musser; 9 Page(s)

For Meera, the revolution began with a single rupee. When a social worker came across Meera's unmapped village in the hills of Uttar Pradesh in India three years ago, he found that the entire population was in hereditary debt bondage. It could have been in the time of their grandfathers or great-grandfathers-few in the village could remember-but at some point in their past, the families had pledged themselves to unpaid labor in return for loans of money. The debt passed down through the generations. Children as young as five years old worked in quarry pits, making sand by crushing stones with hammers. Dust, flying rock chips and heavy loads had left many villagers with silicosis and injured eyes or backs.

Calling together some of the women, the social worker proposed a radical plan. If groups of 10 women agreed to set aside a single rupee a week from the tiny sums the moneylenders gave them to buy rice, he would provide seed money and keep the funds safe. Meera and nine others formed the first group. The rupees slowly mounted up. After three months, the group had enough to pay off the loan against which Meera was bonded. She began earning money for her work, which greatly increased the amount she could contribute to the group. In another two months, another woman was freed; the following month, a third came out of bondage.

Reviews: "The World is Broad and Wide"; April 2002; Scientific American Magazine; by Peter Renz, Staff Editors; 2 Page(s)

Why is The Annotated Flatland piled in heaps at the front of the Harvard Coop? Partly because of the strengths of Flatland itself and partly because of Ian Stewart's annotations. Edwin A. Abbott published Flatland in 1884. More than 12 editions are available today, a measure of the book's appeal. It is a social satire that carries readers beyond conventional ideas and surface appearances to an appreciation of new worlds-those of higher-dimensional space.

Many satirists have used voyages to fantastic lands as a means to develop social commentary; Swift's Gulliver's Travels is a classic example. The science in such works is often itself a parody, like that which Gulliver sees on his voyage to Laputa. In contrast, Abbott gets the science right. Included in this edition is the introduction written by William Garnett in 1926 that recommends the book as a guide to the geometry of spacetime and relativity. Indeed, Flatland has introduced countless readers to the geometry of higher dimensions, having been "read by every self-respecting physicist, mathematician and science-fiction writer, inspiring sequels, elaborations and imitations," as Edward Rothstein observed last year in the New York Times.

Puzzling Adventures: A Fairy Tale; April 2002; Scientific American Magazine; by Dennis E. Shasha; 1 Page(s)

In a mythical land, fairies visit children at night and leave them pearls. But each fairy is attracted only to a particular color. Suppose, for example, that a fairy named Liane is attracted to the color aqua. While making her nightly visitations, she will leave a pearl on a child's bedside table for each aqua star she sees above the child's head. If a fairy named Ariana, who is attracted to crimson, flies with Liane and sees a child with a crimson star, she will leave a pearl on the child's table. So a child having both crimson and aqua stars would receive two pearls. Your task is to find out which fairy is attracted to which color.

Here is what you know: 1. The fairies' names are Juliana, Katiana, Oliviana, Anya and Heather. 2. The colors are silver, sage, gold, rose, turquoise, ivory, violet, emerald and earth. 3. At least one fairy likes turquoise and one likes earth. 4. The children are Augustine, Jonathan and Theo. 5. Augustine has rose, turquoise and violet stars above his head. Jonathan has sage, violet and ivory. Theo has sage, violet and emerald.

Working Knowledge: Grow, Then Kill; April 2002; Scientific American Magazine; by Mark Fischetti; 2 Page(s)

You've had a fever for two days and have been coughing up phlegm, so you visit your doctor. He examines you, asks a few questions, suspects a bacterial infection and says, "I'm going to do a lab test." While you open your mouth and say, "Aaah," he rubs a long swab against the back of your throat to grab some infected cells. He then sends the swab to a lab at a local hospital or health department. If he had suspected other pathogens, he would have taken a sputum, blood, urine or stool sample and sent that, too. You go home, miserable, and wait for the results.

At the lab a technologist unpacks the sample at a bench beneath a hood that draws air away into a filter system. That way, pathogens don't become airborne in the room. From there, the specimen can undergo a variety of tests done in series, each step narrowing its possible identity until one specific pathogen is determined. The most common sequence in dealing with a bacterium is to grow more of it in a lab dish and then test it with carbohydrates and antibiotics to assess what it is and which drugs might kill it most effectively [see illustration at right]. Two days after your visit to the doctor, you get your test results.

Technicalities: Bringing the Net to the Bedroom; April 2002; Scientific American Magazine; by W. Wayt Gibbs; 3 Page(s)

SAN FRANCISCO-When I first set out to build a better wake-up machine 18 months ago, it did not once occur to me to connect the mini blinds on our bedroom window to the Internet. I want to be very clear about this: I'm not one of those wacko Webcam exhibitionists. My wife and I like our privacy, and those thin pecan strips are all that shield us from the cars and electric buses that creep past the other side of that window day and night. It's just that somewhere along the tortuous path of invention, putting the blinds online seemed the most feasible and elegant way to solve my problem. And now it wouldn't surprise me if one day the drapes in your house-along with the security system and the heat pump and various other appliances-are plugged into the Net, too. You might be surprised at how little technical expertise is needed to create the connecting electronics and software.

For me, the whole thing started with a simple motivation: hate. I hate alarm clocks. My theory is that over millions of years, evolution has hardwired the human nervous system to rouse in two ways. There is the gradual stirring in response to the warming pink glow of sunlight on the eyelids. And there is the startled jolt of adrenaline in response to the roar of a leopard-or the wail of an alarm. That may not be scientific fact, but that is how it feels to me. Besides, researchers in Siberia reported recently that the circadian hormone cycles of experimental subjects who awoke in darkened rooms tended to shift a little later each day. But subjects rising to a simulated dawn held comfortably to a 24-hour cycle.

On the Web; April 2002; Scientific American Magazine; by Staff Editor; 1 Page(s)

Anti Gravity: Copy That; April 2002; Scientific American Magazine; by Steve Mirsky; 1 Page(s)

It was the best of times, it was the worst of times,1 it was the New York Times. Specifically, it was a Times article that discussed computer programs and other techniques designed to root out plagiarism.2 The article revealed that there is now software that can look for a lengthy passage, like a string of pearls,3 in a new document that is identical to a passage in a previously published work. In another method, every fifth word from sample passages is removed, and the author has to fill in the blanks4 to reveal his or her familiarity with the work. These high-tech ways to spot literary theft will surely rob copycats of the sleep that knits up the raveled sleave of care.

When I first read the Times article, I remember thinking, it's a good thing6 and attention must be paid.7 After all, as a writer, I find plagiarism to be a constant concern. (Although from time to time, I have to admit, I shall consider it.8) Of course, it can be hard to define. When you steal from one author, it's plagiarism; if you steal from many, it's research.9 One might say that a writer should neither a borrower nor a lender be.10 On the other hand, imitation is the sincerest form of flattery.

Ask the Experts; April 2002; Scientific American Magazine; by Staff Editor; 1 Page(s)

R. Michael Barnett of Lawrence Berkeley National Laboratory and Helen R. Quinn of the Stanford Linear Accelerator Center offer this answer, parts of which are paraphrased from their book, The Charm of Strange Quarks: In 1930 Paul Dirac formulated a quantum theory for the motion of electrons in electric and magnetic fields, the first theory that correctly included Einstein's theory of special relativity in this context. This theory led to a surprising prediction-the equations that described the electron also described, and in fact required, the existence of another type of particle with exactly the same mass as the electron but with a positive instead of a negative electric charge. This particle, which is called a positron, is the antiparticle of the electron, and it was the first example of antimatter.

Its discovery in experiments soon confirmed the remarkable prediction of antimatter in Dirac's theory. A cloud chamber picture taken by Carl D. Anderson in 1931 showed a particle entering a lead plate from below and passing through it. The direction of the curvature of the path, caused by a magnetic field, indicated that the particle was a positively charged one but with the same mass and other characteristics as an electron.

Fuzzy Logic; April 2002; Scientific American Magazine; by Roz Chast; 1 Page(s)

NASA Price List (picture)