ABSTRACT
Charles Harrison Blackley had left the printing business in 1855 and enrolled at Pine Street Medical School, Manchester. Blackley performed experiments on himself with various substances, and even performed controls for each experiment. Using a microscope, Blackley discovered that the samples of dust which brought on hay fever attacks contained pollen. By exposing himself and his patients to each agent systematically he discovered which would give the strongest reaction. Blackley investigated pollens from over 80 different types of plant and discovered that grasses caused the greatest reaction. Charles Darwin was fascinated by Blackley’s experiments on whether pollen could be carried large distances in the upper regions of the atmosphere. Blackley knew that asthma could be precipitated by the inhalation of pollen and had invoked an attack of asthma during a number of his experiments. In 1873, Blackley was affiliated to the British Homeopathic Society and became an Honorary Member of the Manchester and Salford Homeopathic Dispensary.
