Johann Thudichum was a prolific medical scientist and an important pioneer in biomedical research in the second half of the 19th century. Born in Budingen, Germany, he attended medical schools in Giessen and Heidelberg (1847-1851). In Heidelberg he was in contact with Wilhelm Bunsen (1811-1899), the inventor of spectrography, a technique he used to great effect in later work. On his return to Giessen, he spent a year in the laboratory of Justus Liebig, mastering Liebig’s novel methods of chemical analysis, and then opened a medical practice in Giessen.


Thudichum was denied a post in the pathology department at Giessen University and, suspecting that this was a politically motivated decision because he had taken part in the 1848 revolution, he emigrated to London in 1853. He brought with him analytical apparatus from Liebig’s laboratory which he subsequently used to good effect in analysing organic compounds he extracted from various biological sources.


He settled in London where he practised medicine and, at the same time, carried out research (and lectured) in medical chemistry; this brought him to the attention of John (later Sir John) Simon, a surgeon/pathologist at St Thomas’ Hospital and the Medical Officer of Health in the UK who became Thudichum’s chief patron. Both believed in the importance of chemistry in the understanding of disease.*


Simon was appointed Medical Officer to the Privy Council where he instigated science-based investigations in public health. Thudichum joined Simon’s research team. His first ‘commission’ was to investigate the prevalence of parasitic diseases (trichinosis) in meat sold in London markets. The report he presented in 1866 to the Society of Arts, Manufacturing and Commerce (‘Diseases of meat as affecting the health of the people’) earned him the Society’s silver medal and a secure future in Simon’s team. In 1865, Thudichum was appointed to a lectureship in pathological chemistry at St Thomas’ Hospital, where he was funded to set up a laboratory.