PROFESSOR Angus McIntosh, the eminent linguist who as the first Forbes Professor of English Language at Edinburgh University was one of the prime movers in the creation of the School of Scottish Studies, has died at the age of 91.

A fellow of the Royal Society of Edinburgh and a fellow of the British Academy, McIntosh spent 34 years collaborating with Peter Samuels and later Michael Benskin on A Linguistic Atlas of Late Medieval English (LALME), which since its publication in 1986 has come to regarded as the essential reference work for the period, ranking alongside the Middle English Dictionary and even the Oxford English Dictionary.

Born near Sunderland, Co Durham, to Scottish parents, McIntosh graduated with a first class honours degree in English Language and Literature from Oriel College Oxford before spending two years on a Commonwealth fellowship at Harvard, where he met his first wife Barbara. In 1938, he returned to Britain to take up a lectureship in the Department of English, University College, Swansea.

His academic career was interrupted by the Second World War. He first served as trooper in the Tank Corps, but later went on to become a major in military intelligence.

It was during the latter period that, by a happy accident and with a single American colleague, he succeeded in surrounding and capturing the fleeing Japanese delegation to the Third Reich in Gstaad.

His most significant war work was at Bletchley Park as one of the cryptographers and translators who succeeded in decoding signals traffic encrypted by Germany's famous Enigma machine. His time at Bletchley strongly influenced his thinking about empirical research problems in the history of English. In particular, he foresaw the potential of computers as a tool to aid linguistic analysis.

After an eventful war, McIntosh returned to academia and took up a lectureship at Christ Church Oxford. In 1948, he moved to Edinburgh as the first Forbes Professor of English Language and General Linguistics. He was to spend the rest of his academic career there, building an international reputation for the Department of English Language. As soon as he arrived in Edinburgh, McIntosh became involved in what was a stimulating and innovative period in the Arts faculty's history. He was one of the prime movers in the founding of the School of Scottish Studies and of the Department of Linguistics, of two major dictionary projects and of the Linguistic Survey of Scotland.

It was while he was assessing the returns from the postal questionnaire for the Linguistic Survey of Scotland that he began to see the possibility of applying the methodology of modern dialect surveys to the investigation of past stages of English and Scots. The method he devised became known as the Fit-Technique and it was to revolutionise dialect study in historical linguistics.

In the early stages of what became the Middle English Dialect Project, McIntosh was joined by Michael Samuels, who was at the time a lecturer in the department, later to become Professor of English Language at the University of Glasgow. There began a close association between the two English Language departments.

The project later benefited from the contribution of a third major collaborator, Michael Benskin, originally a PhD student of Samuels and later Professor of Older English at the University of Oslo.

LALME was not the only major project in which McIntosh was deeply involved. Out of his work for the Linguistic Survey of Scotland came the introduction to a Survey of Scottish Dialects, published in 1952. He worked hard to set up the Joint Council for the Scottish Dictionaries and was a tireless supporter of both the Scottish National Dictionary and the Dictionary of the Older Scottish Tongue.

Extensively published on a wide range of linguistic topics including papers on the stylistics of Shakespeare, D H Lawrence and Gerard Manley Hopkins.

The recipient of the Sir Israel Gollancz Prize of the British Academy, McIntosh was awarded a host of academic honours, including last year an honorary doctorate from Edinburgh.

His successor, Professor Heinz Giegerich, described him then as "a man who combines broad and eclectic interests with a focused determination to undertake and to steer to completion pioneering projects of colossal size and importance.

Personally, he is characterised by courtliness and elegant wit;

academically he has been a formidable theoretician of language and a painstaking collector and analyst of complex linguistic data. He has also been a generous intellectual catalyst and a patient consultant to students and colleagues who have been intelligent enough to ask his advice."

He paid tribute to the foundations laid by McIntosh, which had brought about a flourishing institute which enjoys collaboration with internationally-renowned scholars and organisations.

McIntosh married his first wife, Barbara Bainbridge, a New Englander, in 1939.

They had two sons and a daughter, David, Christopher and June, and 11 grandchildren. After Barbara's death in 1988, he married his second wife, Karina.

Professor Angus McIntosh; born January 10, 1914, died October 25, 2005.