In 1861, Murray met a music teacher, Maggie Scott, whom he married the following year. Two years later, they had a daughter Anna, who shortly after died of tuberculosis. Maggie, too, fell ill with tuberculosis, and on the advice of doctors, the couple moved to London to escape the Scottish winters. Once there, Murray took an administrative job with the Chartered Bank of India, while continuing in his spare time to pursue his many and varied academic interests. Maggie died within a year of arrival in London, but a year later Murray was engaged again, to Ada Agnes Ruthven, and the following year married her.
By this time Murray was primarily interested in languages and etymology. Some idea of the depth and range of linguistic erudition may be gained from a letter of application he wrote to Thomas Watts, Keeper of Printed Books at the British Museum, in which he claimed an ‘intimate acquaintance’ with Italian, French, Catalan, Spanish and Latin, and to a lesser degree ‘Portuguese, Vaudois, Provençal & various dialects’. In addition, he was ‘tolerably familiar’ with Dutch (including Flemish dialects), German and Danish. His studies of Anglo-Saxon and Mœso-Gothic had been ‘much closer’, he knew ‘a little of the Celtic’ and was at the time ‘engaged with the Slavonic, having obtained a useful knowledge of the Russian’. He had ‘sufficient knowledge of Hebrew & Syriac to read at sight the Old Testament and Peshito’ and to a lesser degree he knew Aramaic, Arabic, Coptic and Phoenician. However, he did not get the job.
By 1869, Murray was on the Council of the Philological Society, and by 1873 had given up his job at the bank and returned to teaching at Mill Hill School in London. He then published The Dialect of the Southern Counties of Scotland, which served to enhance his reputation in philological circles.
Murray had eleven children with Ada (all having 'Ruthven' in their name, by arrangement with his father-in-law, George Ruthven); the eldest, Harold James Ruthven Murray became a prominent chess historian, and one son Wilfrid George Ruthven Murray wrote a biography on his father.
On 1 March 1879, a formal agreement was put in place to the effect that Murray was to edit a new English Dictionary. It was expected to take ten years to complete and be some 7,000 pages long, in four volumes. In fact, when the final results were published in 1928, it ran to twelve volumes, with 414,825 words defined and 1,827,306 citations employed to illustrate their meanings.
In preparation for the work ahead, Murray built a corrugated-iron shed in the grounds of Mill Hill School, called the Scriptorium, to house his small team of assistants as well as the flood of slips (bearing quotations illustrating the use of words to be defined in the dictionary) which started to flow in on foot of his appeal. As work continued on the early part of the dictionary, Murray gave up his job as a teacher and became a full time lexicographer.
In the summer of 1884, Murray and his family moved to a large house on the Banbury Road in north Oxford. Murray had a second Scriptorium built in its back garden, a larger building than the first, with more storage space for the ever-increasing number of slips being sent to Murray and his team. Anything addressed to ‘Mr Murray, Oxford’ would always find its way to him, and such was the volume of post sent by Murray and his team that the Post Office erected a special post box outside Murray’s house.
Murray continued his work on the dictionary, age and failing health doing nothing to diminish his enthusiasm for the work he had devoted much of his life to. He died of pleurisy on 26th July 1915 and was buried in Oxford.
Murray's biography was written by his granddaughter, K. M. Elisabeth Murray: Caught in the Web of Words: James Murray and the Oxford English Dictionary (Yale University Press, 1977, ISBN 0-300-08919-8). More recently, Simon Winchester published The Meaning of Everything: The Story of the Oxford English Dictionary (OUP, 2003, ISBN 0-19-860702-4).
Murray is the "professor" referred to in Winchester's book The Professor and the Madman (UK title The Surgeon of Crowthorne), even though he was never actually granted a professorship by Oxford. Dr. William Chester Minor, a volunteer who worked on the dictionary, was the "madman".