Portrait of the German organic chemist Baron Justus von Liebig (1803-1873). Liebig studied chemistry in Paris, where he became assistant of the French chemist Gay Lussac (1778-1850) and then in 1825 became professor at the University of Giessen near Frankfurt, Germany. Here Liebig founded a leading laboratory and proved himself one of the great chemistry teachers of all time. In 1830 he developed a quick and accurate method for the analysis of organic compounds. Liebig also recognised that carbohydrates and fat are the fuel" of the animal body and suggested the use of potassium and phosphorus as fertilizers in agriculture."