BELLS will ring throughout Britain tomorrow, and also in Australia, the United States, and New Zealand, to mark the tercentenary of a pioneering 17th-century bell-ringer who was buried in St Andrew Undershaft, in the City of London, on 16 November 1713.

The ringer was Fabian Stedman, who devised a method of change-ringing of extraordinary beauty and variability, which has been rung ever since. He also wrote one and published two of the first books on the principles of change-ringing, which furthered its development. His sobriquet is "the father of bell-ringing".

At St John the Baptist, Yarkhill, Hereford diocese, where Stedman was baptised in 1640, and where his father, Francis, was Rector, a new ring of eight bells has been installed to commemorate his life and work. A peal (5040 changes) of his own method, Stedman Triples, was due to be rung on the bells yesterday, in his memory.

In the City of London, peals of Stedman are planned for Saturday at St Katharine Cree, St Mary-le-Bow, and St James's, Garlickhythe. About 6000 churches in the UK have rings of bells, and Stedman will be rung to peals in many of them, as well as touches of 300 changes and 1713 changes, composed for the occasion.

Fabian Stedman did not follow his father and brother into Holy Orders, but, aged 15, went to London to learn the printing trade. There he took up the new and rapidly growing art of change-ringing, joining the society called the Scholars of Cheapside, at St Mary-le-Bow. He was highly regarded as a ringer by the time he was 23; later, he joined the Ancient Society of College Youths, of which he became Master in 1682. It is still the most influential ringing society today.

As a printer, Stedman was well placed to help with the publication in 1667 of the first book on ringing, Tintinnalogia; and ten years later he wrote his own book, Campanologia, which drew together all the current knowledge of change-ringing, both within and outside London. At a time when ringers were scattered about the country, this printed collection of information about the principles of ringing and developments in bell-hanging was invaluable.

Campanologia contains, among many now-vanished ways of permuting the bells, Stedman's greatest legacy to ringers: the Principle that bears his name. Simple enough to be rung well by moderately good ringers, Stedman is also complex and mathematically variable enough to engage the minds of the cleverest. With its blend of musicality and intricacy, it is rung everywhere, from village churches to St Paul's and Westminster Abbey - more often than not it is the method of choice for state occasions.

The basic Principle always involves changes on an odd number of bells: five, seven, nine, 11, and upwards. The largest bell (lowest note) in the tower then sounds at the end of each row, making an even number of bells in all (six, eight, ten, 12, or more), and setting a steady rhythm.

A bell-shaped bronze plaque, erected in 1983, commemorates Fabian Stedman at St Andrew Undershaft. Although the church has six 16th- and 17th-century bells, they are not hung for change-ringing.