Before the peal can be started, the bells must be rung up or “raised” to the inverted position, which the ringer achieves by a series of steady strokes, each pull increasing in length until it is balanced; at the end of the peal this process is reversed. When bells are merely chimed they are not “raised,” but the rope is pulled each time sufficiently to allow one stroke of the clapper. By means of an ingenious apparatus invented by the late Canon Ellacombe, this can now be done by one man if necessary, the muscular effort required being reduced to a minimum. But change-ringing is a real science, and entails long and assiduous practice and considerable muscular exertion. It is, in fact, one of the best forms of physical exercise conceivable, and must have proved a godsend in that respect to many men whose opportunities would otherwise be limited. Its elementary principle is, of course, that the bells should be rung in succession, but in a varying order. The method in which the succession varies is the foundation of the various forms known vaguely to most of us as Grandsire Triples, Treble Bob-Major, and so on. They are founded on a recognized arithmetical basis, that of permutations, or the number of arrangements possible of any given number of objects. We know that three letters or numbers can be arranged in six different ways: 123 132 231 213 312 321 Thus, on three bells, only six changes can be rung so as to vary the order each time, and we must then begin over again. With four bells we have a choice of twenty-four changes, which might run as follows: 1234 3124 4321 4213 2134 1324 4312 4231 2314 1342 4132 2431 2341 3142 1432 2413 3241 3412 1423 2143 3214 3421 4123 1243 This method is known as “hunting the treble up and down,” and was invented by Fabian Stedman, a Cambridge printer, who printed in 1667 the earliest treatise on change-ringing. If the above table is carefully observed, it will be seen that the first bell, or treble, shifts its place by one each time, backwards or forwards, while the other three only change six times in all; in other words, if the treble was omitted it would be a peal of six changes on three bells. [Illustration: _Plate 18._ THE TENOR BELL OF EXETER CATHEDRAL, CALLED “GRANDISON.” Recast by Taylor, 1902. (See page 44.)]