Died: 6 November 1934 in Dowanhill, Glasgow, Scotland

James Gray's parents were Annie Gordon (born Gullatown, Fife in 1850) and Andrew Gray. Andrew Gray was a famous scientist and mathematician who was born in Lochgelly, Fife in 1847. He had served as Private Secretary to Sir William Thomson (Lord Kelvin), was Professor of Physics at University College, Bangor, North Wales, and finally Professor of Natural Philosophy at Glasgow University. Among his publications were Absolute Measurements in Electricity and Magnetism (1883), (with G B Mathews) Treatise on Bessel Functions (1895), and The Scientific Work of Lord Kelvin. James Gray had seven siblings: John (born 1872), Annie (born 1874), Margaret (born 1879), Isabella (born 1882), Thomas (born 1884), Kenneth (born 1886), and Euphemia (born 1889).

Although James was born in Glasgow, his father was at this time professor at Bangor and James attended Friars Grammar School, Bangor, Caernarvonshire. After completing his school education, Gray entered the University College of North Wales.

In 1899 Gray's father was appointed to the Glasgow Chair and he moved to Glasgow to continue his undergraduate studies. He graduated with a B.Sc. in electrical engineering and was appointed an Assistant Lecturer in Applied Physics at Glasgow University in 1904. Four years later he was promoted to Senior Lecturer. During World War I Gray undertook scientific work in naval and aerial defence and in navigation. In 1920 he was appointed Professor of Applied Physics. A newspaper report in The Scotsman on Saturday 2 October 1920 stated:-

NEW GLASGOW PROFESSOR

Glasgow University Court have appointed Mr James Gordon Gray, D.Sc., to the Cargill Chair of Applied Physics, established at Gilmorehill through the generosity of Sir John T Cargill, Bart. The second son of Professor Gray, F.R.S., Professor of Natural Philosophy in the University, Dr Gray has for some years been performing the duties of a Professor of Applied Physics, conducting the classes in physics in the University for engineering students and for students of medicine. He is a graduate of Glasgow University, and has become widely known for his original scientific work.

Gray was a member of the Edinburgh Mathematical Society, joining in March 1909. He was also a member of the Institute of Electrical Engineers. He was elected to the Royal Society of Edinburgh on 18 January 1909, his proposers being Andrew Gray, William Jack, Cargill Gilston Knott, George Chrystal.

An obituary, written by Robert Alexander Houstoun, appears in the Proceedings of the Royal Society of Edinburgh, Volume 55 (1934-35), 154-155. 
We give a version of this obituary at THIS LINK.

After his death The Scotsman published the following obituary:-

SCOTS SCIENTIST DEAD
Professor J G Gray, Glasgow 
APPLIED PHYSICS

A Scottish scientist of world-wide reputation, Professor James Gordon Gray, D.Sc., F.R.S.E., M.I.E.K., of Glasgow University, died yesterday in Glasgow. Professor Gray occupied the Chair of Applied Physics, and was widely known for his experiments and original scientific work. He made valuable contributions to aeronautical discoveries in the form of gyroscopic instruments for cloud flying and bomb sighting. During the war he conducted experiments on behalf of the Allied Forces, employing gyroscopic principles in naval and aerial defence and in navigation.

Since the war Britain has benefited further from Professor Gray's experiments, and when the Cargill Chair of Applied Physics was instituted in Glasgow in 1920 his appointment to the Professorship met with the warm commendation of scientists all over the world. Previously he had declined two tempting offers from America to carry on research work in applied physics in that country. Professor Gray took a prominent part in building up the organisation by means of which his department at the University was brought to its present high state of efficiency.

CO-OPERATED WITH HIS FATHER

Much of his gyroscopic work was carried out in close co-operation with his father, the late Professor Andrew Gray, of the Natural Philosophy Chair in Glasgow University. Along with his father, too, he planned the building and equipping of the now Natural Philosophy Institute of Glasgow University. Professor Gray took a keen interest in the Royal Philosophical Society of Glasgow, and rendered valuable service to its mathematical and physical section. For some years past he had been engaged perfecting apparatus and methods for use in the production of gyroscopic helms and stabilisers for aerial and marine craft. A native of Glasgow, Professor Gray, received his early education at Friars Grammar School, Bangor, and subsequently entered the University College of North Wales. In 1904 he joined the staff of Glasgow University, and lectured in the Department of Applied Physics. He was unmarried. His publications included "A Treatise on Dynamics" (with his father), and about 150 scientific papers and patent specifications. He was the pioneer inventor of the inductor compass used by Colonel Lindbergh in his Atlantic flight.

His bequest to the University of Glasgow was reported shortly afterwards:-

Glasgow Professor's Bequest 
APPARATUS FOR UNIVERSITY

Professor James Gordon Gray, D.Sc., M.I.E.E., F.R.S.E., of La Mancha, Dowanhill, Glasgow, Cargill Professor of Applied Physics in the University of Glasgow, a famous authority on gyroscopes, and author of numerous scientific papers, son of the late Professor Andrew Gray, F.R.S.

Personal estate in Great Britain ... £6408.

1. R A Houstoun, James Gordon Gray, D.Sc., M.I.E.E., Proc. Roy. Soc. Edinburgh 55 (1934-35), 154-155.