books
Seeing Molecules In Context
The Independent, called "Molecule of the Month." Other, more lighthearted ones, developed from pieces in his 'Rad icals" column for the magazine Chemis try in Britain. And some of the subjects, Emsley notes in the books introduction, have 'simply taken my fancy." In "Molecules at an Exhibition," the in the foods we eat. Another, "Starting author has elaborated on the subjects, Reviewed by Eileen L. Lewis lives, saving lives, screwing up lives," adding background material, interesting f you ask children to describe a scien considers molecules that can help and side issues, and historical perspectives, tist, they often talk about someone harm the young; and a third, "Elements as well as his own personal views so that who has white fuzzy hair, wears glass from Hell," presents molecules that are a broader perspective on each molecule es and a lab coat, and knows lots of sci mainly malevolent. Each gallery contains emerges. about 10 portraits. ence facts. The wonderful thing about these galleries is that Children are not alone in that within each, the molecules last perception—that experts are connected. They may in science or any other field work synergistically or in simply know more facts than opposition to each other to novices. Its an idea that has HoC Selenium produce the effects we ex received considerable indi CH, perience, but they relate to rect support in recent years, as each other, and Emsley ~|C*r a number of books have pro helps us draw the connec fessed to tell all you really need to CHo Ο tions b e t w e e n them. In know about science, history, or other HoC. each portrait, he ties together the struc topics. By and large, these books offer a ture and function of particular molecules clearly presented collection of important -Ν in ways that make them *N' facts or events and perhaps some elabo very accessible to general ration. But the facts seem to have little CH 3 readers, who not only will connection to one another, Caffeine gain information, but also and the books rarely con will truly be able to add sider causality. •COOHl that new understanding to Such books view learn .CH 3 their existing knowledge in ers as empty vessels who Lead Arachidonic useful ways. simply absorb given infor acid mation. But educational re There's something in this search shows that if learn book for everyone. Emsley ing is to be meaningful, it must be con uses chemistry to help ex structed by the individual. That person plain the stories you hear must make sense of new ideas and see about the effects of chocolate by looking Portraits of molecules w h e r e those ideas fit into existing at its three key molecules. Yes, the cocoa arranged in 'galleries7 with knowledge. Examination of the miscon in chocolate can trigger a migraine at ceptions people have makes clear that tack, and Emsley gives the best explana different themes help we look for connections and try to find tion I've seen for why some people causality in everyday experiences. Re crave chocolate. His discussion of caf readers make sense of facts search has also shown that new knowl feine's history, sources, effects, and edge is particularly useful when it's built myths is delightful, and it branches out and build on what they know upon and integrated with solid existing to provide other fascinating bits of in understanding. formation. Within this portrait, for ex "Molecules at an Exhibition: Por ample, Emsley notes that, despite wide "Molecules at an Exhibition: Portraits traits of Intriguing Materials in Ev spread belief, cocaine was never in of Intriguing Materials in Everyday Life" eryday Life," by John Emsley, Oxford Coca-Cola. is not a reductionist book of facts. Writ University Press, 198 Madison Ave., New ten by John Emsley, science writer in res The book is full of such wonderful tid York, N.Y. 10016, 1998, 250 pages, $25 idence in the chemistry department at bits. You can open it anywhere and read (ISBN 0-19-850266-4) Cambridge University in England, the about something fascinating. I found out book supports and encourages readers to why my husband's feet smell so terrible make sense of the material it presents. and what he can do about it. The portrait Emsley's exhibition evolved from of selenium is quite wonderful and use As the title suggests, the book is a col lection of "portraits" of molecules, ar newspaper and magazine articles he has ful. It explains, for instance, how to ranged into eight galleries, each with a been writing for many years. Some of the make mercaptans smell even worse—re common theme. One gallery, for exam subjects in these portraits first appeared place the sulfur in them with selenium. It ple, called "Nearly as nature intended," is in a regular column Emsley wrote from also details information on selenium an exhibition of some curious molecules 1990 to 1996 for London's newspaper, sources in food and how this element
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protects us from the toxic effects of oth er elements like mercury, cadmium, ar senic, and lead. Emsley examines common misunder standings about the effect of salt on healthy adults and provides great general dietary information for everyone. He ex plores many current health concerns— like the role of folic acid in pregnane}, where he suggests that the recommend ed daily allowance (RDA) may be too low. He provides good reasons why new mothers should breast-feed, if only for a short time, in his portrait of mothers milk as a source of arachidonic acid. Al though rarely found in food, arachidonic acid is critical to the rate of development of a baby's brain and blood vessels, and Emsley makes a good case for adding it to infant formula. Breast milk, he notes, also contains colostrum, a natural antibiot ic, and the mothers antibodies. Breast feeding reduces the threat of illnesses like gastroenteritis, which can be life-threat ening in developing countries where an tibiotics are not readily available. There's a comprehensive discussion of metals and salts in Gallery 2—"Testing your Metal." Yes, I fear Emsleys also a punster. In a portrait of "Sexual chemis try—nitric oxide," Enisle}' not only ex plains how the molecule works, but passes on some of his collection of puns on the name of this molecule, gathered from the popular press: NO sex, NO won der, NO way, NO news is good news, and NO is the way our body says "yes." De spite the puns, NO does play mam7 amaz ing and important roles in our bodies. Best of all, anyone reading this book will come away with a greater understanding of the body and how it works. There is a frightening portrait of the cheap and easy-to-make nerve gas sarin in the "Elements from Hell" gallery. It de scribes production of the gas in Nazi Ger many in 1944. Even though the Allies had no knowledge of the gas or defense against it, Hitler did not use it as a weap on because he believed the Allies would retaliate with the same chemical. Emsley goes on to discuss the details of sarins effects, symptoms, and antidote, as well as some of its recent uses, including a terrorist incident in the Tokyo subway system in 1995. In "Poisoned by stealth—lead," Enis le}' takes a comprehensive and historical look at the evidence for atmospheric lead pollution long before the Industrial Revolution. He traces the uses and pollu tion from lead beginning in Roman times, through the Middle Ages, and into
the 20th century. One fascinating case of lead poisoning caused the mysterious dis appearance of Sir John Franklins expedi tion, which set off in 1848 to find a Northwest Passage to the Pacific Ocean. Their perfectly preserved bodies, discov ered in the 1980s in permanently frozen graves, show that the explorers died of lead poisoning. The ratio of lead isotopes in their bodies matched that in the solder of food tins found nearby. Since the ratio of lead isotopes varies according to where the lead is mined, these ratios pro vide strong evidence that the expedition members were poisoned by their food supplies. The ancient (ireeks used lead to "sweet en" wine, possibly in the process poisoning themselves. Emsley reports that some modem wines contain levels of the specif1 ic lead compounds found in gasoline if the grapes used to make them were grown near highways. The use of unleaded gaso line has produced a parallel decline in lead additives in the affected wines.
The book begins with a very good in troduction about size called "A quick guide to things large and small." Emsley uses particularly helpful visualizations, such as: "A gram is about the weight of a peanut. A milligram is about the weight of a grain of sand. A microgram is about the weight of a fleck of dust." Like an}' art exhibition, some portraits will have greater appeal than others, but the overall coherence within each gal lery will draw readers on to the next por trait. One can begin reading anywhere in the book, but beware—this book may be difficult to put down, since the portraits do fit together so nicely and each con tains intriguing information and connec tions. As an example, wouldn't you like to find out what really caused Mozart's death? Eileen L Lewis is a chemistry profes sor at Canada College in Redwood City, Calif., and also works for the ModularCHEM Consortium at the University of Califo π n'a, Be ι 'kele ) \ -4
'Measure for Measure' Measure for Measure. Richard A. Young, Thomas J. Glover, vi + 864 pages. Blue Willow Inc., 8241 West Carr St., Littleton, Colo. 80128. 1996. $14.95 papercover (ISBN No. 1-889796-00-X). Pocket sized but packed with conversion factors, "Measure for Measure" con tains more than 39,000 conversions for more than 5,100 different units. De signed with broad appeal for engineers, scientists, teachers, students, and main tenance, construction, and industrial workers, "Measure for Measure" sets a new standard for conversion factor references. Using the International System of Units (SI), this little book that could first defines the base units; in conversions, it gives values in both standard and sci entific notation. Thousands of foreign and ancient conversion factors are listed, including over 20 pages of foreign kilogram conversions. For example, 1 kg is converted to 0.068 516 6 nelli (used in Sumatra for milled rice) and the ancient Egyptian and Hebrew fingerbreadth is converted to meters. Toll-free order line number is (888) 932-1600.
Reference books on CD-ROM For easy access to geographical, political, and economic facts, two of the Cen tral Intelligence Agency's most popular reference books are available on one CD-ROM. The "World Fact Book 1997" and "Handbook of International Eco nomic Statistics 1997" include search and retrieval software that provides the user instant access to a wealth of information. "World Fact Book" is a basic reference of more than 250 countries with numerous explanatory maps and sub ject areas that cover geography, people, economy, government, transportation, communications, and defense forces. "Handbook of International Economic Statistics" provides basic worldwide statistics for comparing the economic performance of major countries and re gions. It reflects the creation of new nation-states and the realignment of regional economic groupings, with emphasis on the worldwide import and ex port business. The CD-ROM is available from the National Technical Informa tion Service, (800) 553-6847, for $59 plus $5.00 handling fee; order number PB98-500424KMN.
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