We all know that the risks we face depend not just on who we are but where we are. California is the most earthquake-prone state in the continental United States but, even within California, the hazard is far from uniform. San Diego is at scant danger compared with the San Francisco Bay area, for example. And within the Bay area itself, your fate during an earthquake depends on the type of structure you're in and whether tectonic convulsions can liquify the ground beneath you.

"Wouldn't it be nice," asks Mark Monmonier in the preface to Cartographies of Danger, "to have no-go, no-build, or no-live maps for all kinds of nasty surprises?" He answers his own question with a book full of well-presented maps. Those maps presented the author with an immediate danger-namely, that by the third chapter, the readers would start skimming at high speed. Fortunately, thanks to Monmonier's lucid and stimulating narrative, I never had such a reaction.

The author makes clear early on that cartography is essential for discussing how physical hazards correlate with geography. Only a small number of the risks we face actually do show such a correlation, however. Part of why the book stays interesting is that, with the author's subtle help, we realize that some maps that claim to delineate hazards could actually do more harm than good.

Even though some maps appear to provide important information, on closer inspection they provide the reader with nothing useful. Consider "Estimated Potential for Contamination of the Intermediate Aquifer System in Polk County, Florida," which divides the county into three parts based on a low, moderate, or high degree of hazard. I have no idea what health risks, if any, arise from such contamination; nor am I aware of why it seemed prudent to speak of three discrete categories of risk rather than two or a continuous measure of risk.