Reviewed by: Ersatzstoffe im Zeitalter der Weltkriege: Geschichte, Bedeutung, Perspektiven ed. by Elisabeth Vaupel Rouven Janneck (bio) Ersatzstoffe im Zeitalter der Weltkriege: Geschichte, Bedeutung, Perspektiven Edited by Elisabeth Vaupel. Munich: Deutsches Museum, 2021. Pp. 348. In 2002, the German historian of technology Ulrich Wengenroth published his controversial article, "Die Flucht in den Käfig." He argued that German innovation culture was decisively shaped by the two world wars, which led German science to focus on substitute materials even during peacetime and explained the lagging behind of German science after 1945. Th is view quickly met opposition that led to numerous research projects. The critical discussion of Wengenroth's thesis is the guideline of the present compilation on substitute materials in the age of the two world wars. Asking what was the lasting effect of research on substitutes and their uses in Germany between 1871 and 1945, Ersatzstoffe im Zeitalter der Weltkriege [Substitutes in the era of the world wars] consists of three parts that are instructively introduced by the volume's editor, Elisabeth Vaupel. The first part is dedicated to substitutes for ferrous and nonferrous metals. One of the challenges for the German war economy in World War I was a lack of the strategic metal copper. As Helmut Maier shows in his article on nonferrous metals, major efforts to find a replacement resulted in useful scientific findings in the field of steel production but did not produce an [End Page 276] economic alternative in times of peace. Therefore, Maier argues, the effective innovation and modernization push should be considered a transformation of the culture of innovation. The prevailing practical experience was replaced by scientification. This interpretation is shared by Andreas Zilt, who gives an overview of the endeavors to find a replacement for manganese or at least a way to economize its use, which resulted in an accelerated scientification of materials and process engineering in industry. Addressing the aspect of synthetic rubber, Peter Morris draws a different picture. In his view, World War I was not a crucial factor for the scientific development of this field. Only British attempts to control the world's natural rubber market in the 1920s pushed chemical companies to pick up the question of synthetic rubber again, even though its success remained doubtful for a long time. The contributions of Markus Raasch on liquid propellants and lubricants and Sandor Fehr on Chile saltpeter discuss substitutes for basic chemicals and chemical products. Raasch gives a comprehensive overview of the different approaches undertaken during World War I. In the long run, this led to the foundation of societies and university institutes that were dedicated to the issues of coal research and mineral oil synthesis. Ultimately, all efforts—even under the National Socialist autarky program—remained unsuccessful, because the expansion of science and industry overstretched the financial and economic power of the German Reich. This is not the case, however, with nitrogen synthesis. After a short presentation of the different approaches to synthesis, Sandro Fehr argues that World War I became a decisive innovation driver for the final success of the Haber-Bosch process. Nonetheless, its undisputed international triumph followed only after 1945. The field of luxury food, foodstuffs, and feedstuffs is the subject of the third part of the volume. In his detailed discussion of Coffarom, Claus Priesner presents the insightful case of the hunt for a synthesis of coffee flavor. Although a successful product could not be offered due to an erroneous economic assessment of the market and of the acceptance by customers, Priesner convincingly shows the persistent secondary effects of the undertaking. The most important one was that the research undertaken expanded the methods for classical organic microanalysis, which was essential for the achievements in many other fields such as hormones. Ulrike Thoms sheds light on the topic of the utilization of animal carcasses as animal feed with emphasis on the time of the Great War. Among the different methods applied, meat-and-bone meal prevailed as the dominant one. Its use was continued after the war and underwent a breakthrough after 1945, before it was prohibited at the end of the century. In summary, the book gives an instructive insight into the history...