Risking life to look at a bit of hot virgin rock

"Approaching an active volcano is like walking along the edge of a highway: as long as you stay outside the white line, the passing vehicles can be very menacing but remain relatively harmless. Cross that line and you get crushed," writes Jacques Durieux, founder and director of the Society for the Study of Active Volcanoes. The problem, he adds, is that with volcanoes there is no clear line drawn on the ground. "Only your experience and sometimes your intuition can tell you just how far you can go." The reward, for those who dare, is to watch Earth being born. "I've walked on rocks that are younger than I am," gloats Durieux.

In Volcanoes , Durieux joins forces with the award-winning photographer Philippe Bourseiller, who has been visiting the world's geological hot spots since 1991, when he photographed the biggest eruption of the 20th century at Mount Pinatubo in the Philippines. During the past decade, Bourseiller has got close to and photographed about 60 volcanoes of the 1,500 that exist.

The result is a book to make anyone gawp and marvel. There have been many startling and magnificent photographs of volcanoes, such as those of Maurice and Katia Krafft (who died on the job at Mount Unzen in Japan in 1991); but Volcanoes is visually exceptional. Printed on glossy paper in a large format, it consists of ten extensive sections of photographs interspersed with relatively brief illustrated chapters, beginning with "Beliefs and legends" and concluding with "The science of volcanoes". The effect is awe-inspiring, as you fly high over the 19,000-ft snowy peak of Cotopaxi in Ecuador, peer over the rims of dark craters at molten-red lava lakes in Ethiopia, shudder at sulphur miners in Indonesia and confront a dancing fountain of fire on Reunion through the eyes of an aluminium-suited and helmeted volcanologist. You may not want to go there yourself, but you are glad the photographer did.

In addition, many images are more serene, concerned with human-volcano co-existence, including religious ceremonies; indeed the book stresses the present trend in volcanology away from bravado and the pure pursuit of science towards reaching balanced assessments of the risk posed to human societies living around volcanoes. The tensions that can be generated by any potential eruption near people were controversially dramatised in two books published in 2001 about the Colombian volcano Galeras, though Galeras does not feature here - a reminder of how volcanology, for all its global feel, is also parochial.

About 500 million people are exposed to volcanic risks in various degrees. Two million live around Merapi in Java, 4 million near Popocatepetl in Mexico, 3 million around the foot of Vesuvius in southern Italy. Durieux regards Vesuvius, which last erupted in 1944, as the "catastrophe of tomorrow". Alarmingly, on the basis of the 1631 eruption that left 4,000 dead at a time when the area was sparsely populated, today, within five minutes, 400,000 would die from pyroclastic flows. It would be useless to try to leave the area as the eruption began - "only an advance evacuation of more than 800,000 persons could avoid an unprecedented catastrophe". Such action would require reliable forecasting by scientists and the total cooperation of the population. At present, neither is likely and most Neapolitans prefer to put faith in the liquefying blood of St Januarius, as evocatively shown by Bourseiller.

The science in the book is largely (and somewhat clumsily) relegated to the final chapter, though it does poke through in some earlier vivid "diaries" of visits to eruptions. The immediacy of a diary survives the book's generally poor translation from French. Not only is this stilted, it is frequently unacceptable, sometimes unintentionally comic (a volcano ejects "ponce", ie pumice - excuse my French) and occasionally misleading, as in the regular use of "seism" for "earthquake" - a direct borrowing from the French séisme , a term never used in Anglophone volcanology.

But the photographs more than compensate for the textual weaknesses. Volcanoes is the kind of book that could change a young science student's life.

Andrew Robinson, literary editor of The THES , is the author of Earthshock .