Pamela K. Gilbert's recent book on Victorian medical maps has much to recommend it. She brings the skills of literary and textual analysis to nineteenth-century British and colonial cartography, and the result is an intriguing and relatively unusual study. She focuses on maps that were made to document and explain cholera outbreaks in both London and India, and argues that these maps were important in conveying the medical community's various and changing reasons for the rapid spread of cholera.

The middle decades of the nineteenth century saw the introduction of cholera into Britain (with many believing that it came directly from India), and, as a consequence, studies were conducted and papers published that addressed the ways that cholera spread so alarmingly and quickly. Several schools of thought developed. One focused on the connections between the lack of general sanitation and the appearance of the disease and used maps to show the correlation between poverty, filth, and cholera. A second school, best expressed by John Snow's midcentury publication and maps on the recent attack of cholera in London, looked for more hidden causes, such as contaminated wells and other underground water supplies.

Gilbert largely focuses on explaining these two competing approaches. She is especially effective in showing the significance and novelty of Snow's perspective. In what is perhaps the best-written and compelling chapter in the book, Gilbert examines how social perceptions and cartographic conceptions of two London boroughs, the seemingly aristocratic St. James’ and the supposedly poor and Irish-dominated St. Giles, informed people's understanding of how cholera was communicated. Although cholera had appeared in St. Giles, many were puzzled by the fact that St. James’ was affected so badly during a midcentury outbreak. According to conventional wisdom, the fact that St. James’ was a rich borough should have meant that it was immune, or at least protected, from cholera. Snow's study and mapping led to the conclusion that poverty or wealth were not such significant factors as had been supposed. Rather, he suggested that a well-used water pump in the middle of the borough had been contaminated.

Another strength of the book is that it contributes to a growing trend and literature on the links (or lack) between nineteenth-century Britain and its colonies. In the book's last two analytical chapters, Gilbert examines how the colonial medical community at first mirrored but then differed from its British counterpart in how it understood and cartographically explained the spread of cholera. One senior medic in India, for instance, proposed that cholera was spread by the monsoon winds, an opinion that was not shared by his British colleagues. Two reasons for the divergence of opinion were the lack of communication between colonial and British authorities and the assumption that colonial medics were inferior in their training and expertise. Despite differences, though, it is clear from the maps themselves that colonial medics were steeped in a European cartographic tradition and incorporated little, if any, indigenous mapmaking techniques or perspectives. While the arguments explaining the spread of cholera may have been different from those expressed in London, the cartographic idiom was the same.

Gilbert's book, then, is primarily a study of how maps, in the broadest sense, since she includes topographical descriptions in Charles Dickens's work, illustrated reasons for the spread of cholera. Less satisfying is her treatment of the scientific and historical contexts of this mapping. For example, little is written about cholera itself, such as what people believed it to be and how those notions changed as discoveries were or were not made during the course of the century. Similarly, it would be interesting to learn more about both the mapmakers themselves and the implied and actual readership. When did medical research first incorporate mapping, and how did these medical researchers first learn about how to map? Also, how many studies on cholera were published, what proportion of those contained maps, and what was their print run? In other words, a more detailed history of the maps, their makers, and their readership would have reinforced the books’ claims regarding the significances and changes identified in Victorian cholera maps.

Overall, Gilbert's book is a welcome study that will be of interest to several groups of academics beyond historical geographers and cartographic historians. Nineteenth-century British (and especially London) historians, for instance, will appreciate her treatment of the Victorians’ response to the cholera outbreaks, while empire historians will turn to her discussion of cholera in India. Literature scholars will gravitate to her chapter on Dickens's topographical and sociological descriptions of London.