It was in the late nineteenth century that medicine turned its attention to irrational fears. The German physician Carl Westphal (1833-1890) made the initial diagnosis of a phobia, agoraphobia, the fear of open spaces, in 1871. He studied the behaviour of three otherwise sane and rational men who were terrified of crossing an open city space. Following this diagnosis, the notion that individuals could be overtaken by various form of inexplicable fear was quickly taken up by medical practitioners around the world.
The American psychologist Granville Stanley Hall (1846-1924) soon identified 138 different forms of pathological fear. Not only did these include recognised phobia, such as agoraphobia and claustrophobia, but also some fears that were particular to the Victorian era: amakophobia (fear of carriages), pteronophobia (fear of feathers) and hypegiaphobia (fear of responsibility).
Eventually Hall suggested that emanations from the cat 'may affect the nervous system through the nasal membrane, although recognised as odours'. He remained baffled over why cats seemed to have an urge to get as close as possible to individuals who were scared of them.
Research now suggest that the Victorian urge to classify almost everything was the result of a rapidly changing, industrialising society, where new scientific theories were starting to challenge long-held religious beliefs, explanations and dogma.
 Westphal: Die Agoraphobie, eine neuropathische Erscheinung in Archiv für Psychiatrie und Nervenkrankheiten - 1871
 Stanley Hall: Synthetic Genetic Study of Fear in American Journal of Psychology - 1914