Professional correspondence and papers on the radiography research of James Mackenzie Davidson Letters from various authors to James Mackenzie Davidson relating to the development of radiographic technique and the use of front-line radiological units during the First World War. Also contains a sample of Mackenzie Davidson's copy letters and works, and five letters sent to Lady MacKenzie Davidson following her husband James' death regarding an annual memorial lecture. Remaining papers include obituary and biographical materials on Mackenzie Davidson's life and work. 1886-1926