Grandsire

Grandsire is one of the standard change ringing methods, which are methods of ringing church bells or handbells using a series of mathematical permutations rather than using a melody. The grandsire method is usually rung on an odd number of bells: Grandsire doubles is rung on five working bells, grandsire triples on seven, grandsire caters on nine and grandsire cinques on eleven.

The method was designed around 1650, probably by Robert Roan who became master of the College Youths change ringing society in 1652. Details of the method on five bells appeared in print in 1668 in Tintinnalogia, the first book to be published on change ringing. By this time, Roan had invented a six-bell extension he named "grandsire bob", now known by ringers as "plain bob minor". The description of grandsire predates modern method naming conventions. Grandsire on an odd numbers of bells (as it is usually rung) would share a name with the method known as "plain bob" on even numbers of bells in modern nomenclature. However, grandsire bob is a method separate from plain bob by having the 4-5 dodges and thirds of grandsire doubles, but with long sixths at the back (plain bob doubles have long fifths).

The plain course of grandsire triples takes 70 changes to come back to the beginning, which takes about two to three minutes to ring. To produce longer lengths, periodic alterations to the method are required. These are referred to as "calls", because they are usually announced by the "conductor" or "bob caller". The usual ones are "bobs" and "singles".

The 120 possible changes of doubles could only be rung by the introduction of single changes—that is, changes in which only two bells change position. Only two such singles were required. It was unclear whether the 5040 (7! = factorial 7 = 7×6×5×4×3×2×1) possible changes of triples required a similar compromise. Although attempts at triples compositions appeared in print as early as 1702, and a peal composed by John Garthon was rung in 1718, it was 1751 before John Holt produced the first satisfactory peal. William Henry Thompson, a mathematician, proved in a paper published in 1880 that it was impossible to achieve the 5040 changes using the normal bobs only, without the use of singles or some other type of call. This result had long been suspected by peal composers, but it had not been proved.

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