He then looks at various attempts to expand natural nitrogen flows through mineral and synthetic fertilisers. The core of the book is a detailed narrative of the discovery of ammonia synthesis in 1908 by Fritz Haber - a discovery scientists had sought for over hundred years - and its commercialisation by Carl Bosch and the chemical company BASF. Smil also examines the emergence of the large-scale nitrogen fertiliser industry and analyses the extent of global dependence on the Haber-Bosch process and its biospheric consequences. Finally, he looks at the role of nitrogen in civilisation.