_Gentlemen_, _A constant well-wisher to the Prosperity (though an unworthy member) of your Society_, F.S. _ERRATA._ _Courteous Reader_, _Some few faults have escaped the Press: as page 27 line the 4th, for_ grateful _read_ graceful. _page 31. line the 19th. for_ imitatieg _read_ imitating, _with some others, which you are desired either candidly to amend, or tasitly to pass over._ [Illustration: [Fleuron]] OF THE ART OF Changes. These clear dayes of Knowledge, that have ransackt the dark corners of most Arts and Sciences, and freed their hidden mysteries from the bonds of obscurity, have also registred this of _Ringing_, in the Catalogue of their Improvements; as well the Speculative as the Practick part, which of late years remain’d in _Embryo_, are now become perfect, and worthy the knowledge of the most ingenious. Although the Practick part of _Ringing_ is chiefly the subject of this Discourse, yet first I will speak something of the Art of _Changes_, its Invention being Mathematical, and produceth incredible effects, as hereafter will appear. But first, I will premise a word or two, to shew what the nature of those _Changes_ are. Some certain number of things are presupposed to be changed or varied; as 2.3.4.5.6. or any greater number whatsoever; then the number of things to be so varied must have the like number of fixed places assigned them. As if five men were sitting upon five stools in a row; the stools are supposed to be fixed places for the five men, but the men by consent may move or change to each others places at pleasure, yet still sitting in a row as at first: now this Art directs how, and in what order those five men may change places with each other, whereby they may sit sixscore times in a row, and not twice alike. And likewise a _Peal_ of five Bells, being raised up to a fit compass for ringing of _Changes_, are there supposed to have five fixed places, which time assigns to their notes or strokes; yet the notes of the Bells may change into each others places at pleasure: now this Art also directs the manner and method of changing the five notes in such sort, that they may strike sixscore times round, and not twice alike. The numbers of _Changes_ are thus to be discovered. _Two_ must first be admitted to be varied two wayes; then to find out the Changes in _three_, the Changes on two must be multiplied by three, and the product will be six, which are the compleat number of Changes on three.