How did science influence British imperial ambitions in Africa and how did these imperial endeavors change the scale and scope of scientific practice? These are the main questions in Helen Tilley's thought-provoking book on science, empire, and development during the decades between 1870 and 1950. Her geographical focus lies on the British Colonial Office dependencies today known as Kenya, Tanzania, Uganda, Zambia, Nigeria, and Ghana. Her close reading of British scientific work on these areas leads Tilley to the somewhat surprising conclusion that there never was such a thing as a ‘colonial science’. Rather, she argues, the scientific study of colonial situations and phenomena took place within the core of science. Colonialism did not produce pathological distortions of ‘good’ science. Nor did ‘Western’ science in an authoritative move destroy distinct bodies of knowledge, sometimes referred to as ‘local knowledge’.

These are strong claims that are well argued for. Tilley insists on the spatial characteristics of modern science in order to make her case. She understands science as constructed to be mobile, and she recalls the fact that scientific findings are designed to travel. Thus, ‘there is too much circulation between metropole and colony, across colonies, and between colonies and nations-states to warrant the designation colonial science’ (p. 10). Spatial distinctions however include the notions of a ‘field’ or a ‘laboratory’, where exemplary findings are stabilized and packed in order to survive their shipping across the universal scientific world. Conceiving of Africa as a laboratory has been an essential feature of colonial history. And, consequently, the laboratory is the guiding theme in Tilley's book. She analyses a laboratory for scientific research that produced new techniques of colonial governance, social engineering, and development. But she also reconstructs the genesis of new forms of social criticism and of epistemic pluralism that challenged the very foundations of empire.

Her account starts with the founding of geographical societies during the late nineteenth century. Under the heading ‘An Imperial Laboratory’, Tilley shows how a purportedly neutral scientific interest in exploring Africa impinged on the political partition of the continent. Science, namely geography, set the stage for the Berlin Conference of 1884/5 as it framed the very object for which the European powers began to struggle. Science was not a cover-up of imperial ambitions, as some historians of imperialism have argued, but a core element and a condition of its possibility. Cartography had offered the very paper for the infamous ‘paper-partition’ of Africa of which, as a matter of fact, very little was known.

The first chapter is a prelude to the epoch of in-depth research surveys into the African mainland that kept British colonial administrators busy for decades. By far the most comprehensive endeavor in this respect was the African Research Survey under Malcolm Hailey that started in the late 1920s and resulted in a famous 1938 publication. This multidisciplinary research project aimed at making use of the resources of modern science in order to assist governments in the exercise of their colonial power. Its analysis and contextualization form the backbone of Tilley's book – and also her title is borrowed from Hailey, who presented Africa as a ‘living laboratory’ in the report's introduction.

The second chapter (‘A Development Laboratory’) gives organizational detail on the survey and sketches the growing demand for expert knowledge by colonial administrators in London as well as on the African ground. The remainder of the book then follows disciplinary and inter-disciplinary issues. Based on earlier work by the author, the ‘Environmental Laboratory’ (Chapter Three) and the ‘Medical Laboratory’ (Chapter Four) focus on problems of agriculture and infectious diseases and connect these topics to the newly emerging discipline of ecology. Chapters Five and Six (‘A Racial Laboratory’ and ‘An Anthropological Laboratory’) then show more clearly the subversive impact of scientific field work upon the colonial project. Most important seems Tilley's question as to why all efforts to make racial science a research priority failed despite the fact that the colonial political spheres were largely structured racially. While race biology served as an aid in governing, Tilley shows that scientists also questioned racial categories as meaningful tools in the analysis of human collectives, and that policymakers expressed concerns about the detrimental dynamics of racial hatred. With respect to race, the African laboratory gave rise to an epistemic instability that threatened the racial foundations of empire. The same ambivalence is detected in her study of anthropological research. This discipline used Africa in order to professionalize and counted some strong believers in colonial supremacy. Anthropology was instrumental in detecting local differences, thus structuring the Africans as objects of study. While it reified ethnic and tribal identities and stabilized assumptions about differing stages of collective organization, it also established Africans' agency, autonomy, and knowledge as scientific facts. Some Europeans came to the conclusion that they had more to learn from Africans than to teach them. These findings gave rise to critical debates among experts, administrators, and social critics in the colonial era, which are still salient today. Chapter Seven (‘A Living Laboratory’) narrates masterfully the problems of accommodating different epistemic structures, and of reconciling difference within the universals of modern science. Concepts in current use, such as therapeutic pluralism, and the notion of ethnoscience more generally, can be traced back to the laboratories of science under colonialism.

Tilley's book is a highly welcome analysis of the nexus of knowledge and power because it abstains from simplified explanations. Rich in detail, it offers many examples for epistemic interaction, ambivalence, and variety, which seem hard to accommodate in the concept of an authoritative ‘colonial science’ that purportedly ignored and destroyed local specificities.