Mabel FitzGerald today is best known for her work on the physiology of breathing, specifically for her ‘Observations on the changes in the breathing and the blood at various high altitudes’, published in 1913 and 1914. But her research interests were much broader: she researched and published on bacteriology, including ‘The induction of sporulation in the bacilli belonging to the Aerogenes capsulatus group’ (1911), and combined anatomy and physiology in her work on ‘Origin of the Hydrochloric Acid in the Gastric Tubules’ (1910). Previously, she had worked with Gustav Mann in Oxford on histology, contributing to his publication on tissue response at vaccination sites (1899), and collaborated with Georges Dreyer at the Copenhagen State Serum Institute on finding methods to differentiate between B. typhosus and B. coli in bacteria cultures (1902).
Her own first big research project, however, took her into the world of what today would be called neurophysiology. From 1899, FitzGerald investigated the interrelationship of the grey matter (cell bodies) and white matter (nerve fibres) in the spinal cord of the Macaque monkey. She made hundreds of detailed to-scale drawings of cross-sections of the monkey spinal cord as seen under the microscope, and meticulously measured and compared the size and distribution of grey and white matter areas.
Gustav Mann, under whom FitzGerald was working at the Oxford Physiology Department, later wrote in testimonial for her: “I was so much struck by her great thoroughness that I proposed to her the difficult task of investigating the inter-relationship of the grey and the white matter of the spinal cord of the monkey. In this research she has been engaged for five years. She spent the first three years with work having reference to the minute structure of the grey matter and made a large series of accurate microscopical drawings. The last two years she has devoted to the special investigation of the relative and absolute increase and decrease of the different tracts and of the grey matter.”
The results of FitzGerald’s research were communicated to the Royal Society by FitzGerald’s mentor – and Professor of Physiology – Francis Gotch (women were not admitted to the society at that time), but later published under her own name as ‘An Investigation into the Structure of the Lumbo-sacral-coccygeal Cord of the Macaque Monkey (Macacus sinicus)’ (1906).