THE ALCHEMY OF AIR

A fast-paced account of the early-20th-century quest to develop synthetic fertilizer.

Today hundreds of factories convert atmospheric nitrogen to ammonia in order to manufacture the artificial fertilizers that make modern-day agricultural yields possible. They are based on the technological advance known as the Haber-Bosch process, developed prior to World War I by the German chemists and Nobel laureates Fritz Haber (1868–1934) and Carl Bosch (1874–1940). Hager (The Demon Under the Microscope: From Battlefield Hospitals to Nazi Labs, One Doctor’s Heroic Search for the World’s First Miracle Drug, 2006, etc.) offers a superb narrative of these brilliant men and their scientific discovery. Around the turn of the century, the world faced a shortage of the fixed nitrogen needed to provide food for a growing population. Hager sets the stage by describing the world’s reliance in the 19th century on nitrates from Peru and Chile that could be used as natural fertilizer or to make gunpowder, and finds plenty of human drama in the battles to control the lucrative international trade. Determined to help end Germany’s dependence on South American nitrates, Bosch and Haber worked at the German chemical company BASF to find a way to convert nitrogen into ammonia. Bosch developed the process, and Haber designed bigger industrial plants. By 1944, the Haber-Bosch factory at Leuna—a primary target for U.S. bombers—occupied three square miles and employed 35,000 workers. The author not only illuminates the scientists’ complex work, but also digs into their personal lives. Bosch, a melancholic with a huge villa in Heidelberg, asked Hitler to spare Jewish scientists for the sake of German chemistry and physics (the Fuhrer replied: “Then we’ll just have to work 100 years without physics and chemistry!”). Haber, a Jew, developed the chlorine gas used in World War I, sought a way to extract gold from the oceans to pay off German war reparations and conducted research that led to the development of the Zyklon B gas used in Nazi death camps.

Science writing of the first order.