James Lorrain Smith

James Lorrain Smith (21 August 1862 – 18 April 1931) was a Scottish pathologist known for his works in human physiology, especially his research on respiration in collaboration with John Scott Haldane.

He was born in rural Dumfriesshire where his father Walter was Free Church of Scotland minister in Half Morton parish, a few miles north of Gretna Green. He had several talented siblings, including the mycologist, Annie Lorrain Smith who worked informally at the British Museum. His brother walter became a professor of philosophy in Illinoi while another brother William George became a lecturer in psychology.

He studied arts, then medicine at the University of Edinburgh in 1889. He then became John Lucas Walker Student in Pathology at the University of Cambridge and then a Demonstrator under Professor Charles Smart Roy who recommended him to follow his studies at the universities of Strasbourg under Friedrich Daniel von Recklinghausen. He spent some time at Copenhagen where he studied techniques for analysing gases in blood in Christian Bohr's laboratory before moving to teach at the Queen's College of Belfast and became a professor in 1901. In 1904 he became Professor of Pathology at Manchester and in 1912 moved to Edinburgh to replace Prof William Smith Greenfield. During the war they introduced the antiseptic "Eusol" (Edinburgh University solution) and suggested the idea of using charcoal in gas masks.

Professor Lorrain Smith worked with John Scott Haldane on respiration particularly the transport of oxygen by the blood. The pulmonary condition of intoxication due to excess oxygen or oxygen toxicity is sometimes called "Lorrain Smith effect".

He was elected at the Royal Society on 6 May 1909.

He died on 18 April 1931. A funeral ceremony was held at the University of Edinburgh.