 In 1946 he was appointed professor of chemistry and head of department at Reading University, where he stayed until his retirement in 1966.Guggenheim produced eleven books and more than 100 papers.His first book,"Modern Thermodynamics by the Methods of Willard Gibbs" (1933), was a 206-page, detailed study, with text, figures, index, and preface by F. G. Donnan, showing how the analytical thermodynamic methods developed by Willard Gibbs leads in a straightforward manner to relations such as phases, constants, solution, systems, and laws, that are unambiguous and exact.