This most recent work of Mark Harrison’s grew out of a project to investigate medicine in the British West and East Indies. It well reflects two of his enduring interests: tropical medicine and military medicine. His argument is that the British experience in the two Indies had effects on the medical ideas and practices of the home countries themselves. The book is not, therefore, about British colonial medicine per se since he, for the most part, examines writings pertaining only to parts of the British empire overseas and since the methods of colonial dominion and the ways in which medicine was integrated into them are not his chief focus—these he leaves to his collaborator on the project, Pratik Chakrabarti (whose Materials and Medicine: Trade, Conquest and Therapeutics in the Eighteenth Century also appeared in 2010, from Manchester University). Rather, Harrison carefully summarizes the written opinions of medical practitioners about medicine in hot climates. Harrison therefore describes his work as an “intellectual history of medicine and the dissemination of ideas and practices around the British Empire” (v).

In keeping with his aims, the first part of Harrison’s book is a fine overview of medical ideas, beginning with special attention to the famous Thomas Sydenham and Herman Boerhaave. They and their successors developed a climatological view of medicine, arguing that the particular constitutions of warm climates had particular effects on those not yet acclimatized to them. The Hippocratic view of the importance of airs, waters, and places came to be turned into a view of medicalized climatic zones. As is well known, the category of “fever” preoccupied eighteenth-century medical thinking, and practitioners in the tropics were even more concerned about diseases of that kind. In the middle of the century, Sir John Pringle, the noted author on military medicine and hygiene, persuaded many that fevers were due to putrefactive processes in the body and needed to be treated with “antiseptic” medicines. While fevers had traditionally been treated in Europe by venesection, practitioners in the East Indies moved away from bleeding in the 1760s in favor of purges that were thought to expel “putrid” matter from the body. Among the most widely used medicines in this class were the mercurials, most especially calomel, which Harrison argues was adopted from the medicine of the bazaar: he finds that these kinds of purges were not as noticeable in the West Indies, while medical experiments in support of local methods of treatment, supplemented by postmortem dissections, were carried out in India. By the end of the century, however, William Cullen’s theories about the causes of disease being located in the nervous system grew predominant and brought about a revival of therapeutic bleeding; at the same time, ideas about the physiology of racial difference also started to become discussed. By the early eighteenth century, yellow fever and the diseases of civilization began to dominate medical discourse, much of which was aimed at people who had spent time in the colonies abroad before returning to England, where they took to the spas in large numbers in hopes of improving their health.

From such a brief summary, which cannot do justice to the many medical works that are described and summarized, one can see that Harrison’s argument about colonial medicine effecting British medicine is strongest for the brief period in which local practices in India added weight to theories developed in Britain. Harrison also argues that having medical practitioners think about groups rather than individuals, as company and military surgeons did, encouraged thinking about diseases as distinct entities rather than personal imbalances and treatments such as dosing with calomel that could be applied without much regard for individual constitutions. But while Harrison is always clear descriptively, the causal processes creating change in ideas are not always apparent. Despite his stated intentions, then, Harrison shows empirical practices in the tropics affecting theories only in a few exceptional cases, while it is at places like London and Edinburgh where Sydenham, Pringle, Cullen, and their like produced their books and persuaded their disciples. Practices abroad were “distinctive,” he shows, and sometimes (as with calomel) they were also taken up in Britain. But the mechanisms of “spreading ideas and practices” are uncertain: was it chiefly by personal contact and travel, by the publication of pamphlets and books, by struggles for prestige and power within the profession or the services, or by medical commerce? Harrison offers many important observations about the social context of practitioners overseas, such as their frequently dissenting views on religion and politics, as well as their appreciation of “empirical experience,” but it not clear whether such practitioners were more important for British medicine than those of similar background and outlook who never left the Isles. His concluding chapter gives clear voice to historiographical ideals about the importance of social networks and “reciprocity” that are currently widely shared. Yet the scope of this work does not allow him to explore such aims or to explain the many possible connections between medicine and other kinds of discourses, such as political and scientific ones, despite many provocative observations such as the use of the word “contagion” to describe certain ideas that threatened the establishment during the period of the French revolution and after. To move in such directions would have been to write a book about the period in general. By focusing his remit, Harrison has given us a clear and concise account of British medical ideas related to warm climates, one that will be widely appreciated as an authoritative starting point for the future studies that are bound to emerge from such a rich subject area.