NO ONE who knew James Cobban - headmaster of Abingdon School over two decades - is ever likely to forget him. He was a character. He spoke rapidly and at a volume appropriate for addressing a school assembly in the open air and into the wind. Many were the somnolent members of after-lunch meetings of headmasters or of the Synod jerked visibly back to wakefulness by an explosive "Mr Chairman" from Cobban.

His clarity of vision matched his energy. He nearly always knew what should be done, and colleagues found themselves swept up in the enterprise. Notes from "J.M.C.", written late in the evening and in masters' pigeon-holes before breakfast, worded "Pl. sp." (please speak) or "Action pl.", had to be dealt with at once, and were.

As a result Cobban transformed Abingdon School between his arrival there in 1947 at the age of 36 and his retirement more than 23 years later. The school he took over was a small grammar school of 230 boys, usually called Roysse's after its founder and almost unknown outside the county of Berkshire. The new headmaster quickly realised the opportunity provided by the recently established Atomic Energy Research Establishment at Harwell, manned by hundreds of scientists with clever sons to educate. Despite shortages of money he doubled the area owned by the school and took some pride in ensuring that he left to his successor in 1970 a school of 630 pupils, exactly 10 times the number stipulated by the founder in 1563.

His achievement stands comparison with those of the giants of the profession. In many ways it was more meritorious for, while they took on great schools and made them even better, he alone brought a school from obscurity to national recognition. Since the ability to delegate was the one virtue he lacked, that achievement can fairly be said to have been his alone.

He cared passionately about every aspect of the school's life. Like other direct grant schools, Abingdon (as Roysse's was quickly renamed) had a wide social mix. Cobban believed boys capable of going on to important jobs should know how to behave, and even through the cynical Sixties he included social etiquette as well as moral issues among the lectures he gave to the sixth form each week. He himself was unfailingly courteous to everyone - to colleagues however tiresome, to boys however small or however rebellious, and to parents however unreasonable. He spoke to every single boy as he went about his business and he expected them to respond. After Sunday chapel, boarders paraded past him to be individually greeted by name - usually, but (to the quiet delight of the boys) not invariably, the correct one.

Cobban knew he wanted to be a schoolmaster by the time he left Pocklington School, York, with a scholarship to Jesus College, Cambridge, where he took a first in Classics and the Gladstone Prize. After a year studying in Vienna and Rome, he taught for three years, 1933-36, at King Edward VI School, Southampton. There, he co-authored the Latin reader Civis Romanus (1936) which remained continuously in print for 50 years and sold close to half a million copies.

In 1936 he moved to Dulwich College, where no fewer than 23 of his classical sixth won open awards to Oxford or Cambridge in the three years before the war and his departure for the Intelligence Corps. Having survived the Normandy beaches shortly after D-Day and (thanks to a bedroom door which fell across his bed) a V2 attack in London, he went to Germany as a Lieutenant-Colonel to reorganise local government on democratic lines. He delighted in doing business with his German opposite numbers in Latin when their English and his German ran out, and he brought back a system for filing documents used by the German ministries. At Abingdon School it was widely believed to have been exclusive to the German secret service as it proved impenetrable to everyone but Cobban himself.

In daily conversation as well as in after-dinner speeches, talks and even sermons, laughter was never far away. People left his company warmed by his wit as well as by his interest in them. Yet he had suffered two disasters which would have felled a lesser man. The loss of his two-year-old son in an accident, and then in 1961, after 20 years of happy marriage, the death of his beloved wife Lorna, who had worked tirelessly beside him as the school and their family grew, were blows survived only because of his exceptionally firm faith. His was the simple, straightforward, practical Christianity of a genuinely good man.

With time in retirement to become "a full-time busybody", Cobban completed 10 years as Chairman of the Abingdon Rural District Bench and served for 15 years on the General Synod. He was knighted in 1982 on the introduction of the Assisted Places Scheme of which he was the chief architect. For 27 years he wrote a monthly column for his diocesan magazine and until two years before his death he preached regularly in six churches near his home in Yeovil. He took pleasure in the visits of old pupils even when he could no longer outwalk them on the Downs, and in the company and achievements of an affectionate and talented family of four daughters.

James Macdonald Cobban, headmaster and educationist: born Scunthorpe, Lincolnshire 14 September 1910; Assistant Mas- ter, King Edward VI School, Southampton 1933-36; Classics sixth-form Master, Dulwich College 1936-40; 1946-47; Headmaster, Abingdon School 1947-70; member, General Synod 1970-85; CBE 1971; Kt 1982; married 1942 Lorna Marlowe (died 1961; four daughters, and one son deceased); died Yeovil, Somerset 19 April 1999.