Friedrich August Kekulé (1829-1896) Entered the University as an architecture student. Studied under Liebig (PhD, Giessen). Studied in Paris under Dumas (substitution theory) and Gerhardt (type theory) and came under the influence of Williamson (water type) while studying in London. Professor at Ghent (1858); Bonn (1867). For an interview with Kekulé, click here. Tetravalence of carbon (1859) Structure of benzene (1865) Focussed on the structure of molecules Contributed to the concept of valence along with Frankland Contributed to the marsh gas type along with Odling