(Cottingley Hall. Bingley, Yorkshire, England, b:10 December 1879; d. Oxford, England, 9 February
Priestley was the son of Charles Henry Priestley and Ann Ford Gillies. His family possessed private means, derived from the textile industry. In 1908 he married Elizabeth Stewart, Priestley was educated at Eton and Christchurch. Oxford, where he took first-class honors in physiology soon after the turn of the century. He subsequently achieved medical qualifications at St. Bartholomew's Hospital, and following an additional year of training in Vienna he was appointed director of the chemical pathology laboratory at St. Bartholomew's. The emergence in 1912 of a tubercular condition (from which he suffered for the rest of his life) necessitated his move from London to Oxford in that year. With the outbreak of World War I, Priestley joined the Royal Army Medical Corps; he served with distinction in France and Belgium and was awarded the Military Cross. After the war Priestley returned to Oxford, where he was appointed reader in clinical Physiology. There he spent the remainder of his life, teaching and doing research in physiology and medicine.
Priestley's scientific reputation rests primarily upon his collaboration with his Oxford mentor, John Scott Haldane, which resulted in their classic paper on the regulation of lung ventilation (1905). In the words of G. E. Allen, this paper "offered for the first time a completely workable system for the regulation of the respiratory rate both in terms of the changes in the external environment, and in terms of the regulatory mechanisms within the body" ("J. S. Haldane..." p. 406).
Haldane and Priestley were able to demonstrate that the carbon dioxide content of the blood which depends upon the concentration of carbon dioxide in alveolar air-is principally responsible for changes in both depth and frequency of respiration. Haldane and Priestley built upon Haldane's previous work and that of F. Miescher-Rösch and Léon Fredericq; but most earlier research on respiratory regulation had failed to clarify the relative significance of neural, as opposed to blood-chemical, mechanisms and of carbon dioxide, as opposed to oxygen, levels in the blood. Priestley's share in this work is difficult to assess. The 1905 paper was merely the most notable of Haldane's many technical and conceptual contributions to the field of respiratory regulation, contributions which had begun in the early 1890's before Priestley's arrival at Oxford as an undergraduate and which continued after he went to London to study medicine at St. Bartholomew's. Priestley's later work, principally on regulatory mechanisms in respiration, renal physiology, and blood chemistry, were marked by the technical precision and rigor that he had learned from Haldane. Late in World War I , Priestley joined Haldane and some of the latter's other students in an investigation of the aftereffects of gas poisoning.
An expert bibliographer, Priestley was responsible for the index to the first sixty volumes of the Journal of Physiology and for the editing for some years of Physiological Abstracts. He was joint editor of Human Physiology. A Practical Course (Oxford, 1924) and assisted Haldane in the preparation of the 1935 edition of his Respiration, based on Haldane's Silliman lectures at Yale and originally published in 1922.