This book is a quantitative study of relocation costs among European soldiers in the tropics between about 1815 and 1914. This study, however, has broader implications. For Europe itself, this was the crucial century of the 'mortality revolution', with its profound influence on European and world demographic history. For the history of medicine, this was the transitional century between the kind of medicine that had been practiced in Europe since classical times and the kind of scientific medicine that would be spawned by the germ theory of disease. For Europe's global, political and military relations, this was the final period for the European conquest. For all these reasons, the relocation costs of this period have great bearing on human history.