The combination of several melodic lines obliges the composer to use devices which are unnecessary in homophonic music. A single melody can develop as it pleases. But when two or more are combined each must be so delicately and cleverly fashioned that it can be interwoven with the others in this direction and in that. And here we detect one at least of the reasons why Bach’s melodies are so strangely original, and his tunes so clearly distinguishable from those of other composers. Provided that novelty does not degenerate into eccentricity or extravagance, and that clearness and facility of expression march with agreeableness, a composer’s meritoriousness is proclaimed in his originality.(150) The one drawback is that the ordinary hearer cannot appreciate melodic beauties which are patent only to the expert. But Bach’s melodies are not invariably so handicapped. They are always original, it is true. But in his free compositions the melodies are so natural and spontaneous that, while they sound differently from those of other composers, their naturalness, and the sincerity of feeling that inspires them, make them intelligible to every listener. Most of the Preludes in the _Well-tempered Clavier_ as well as a number of movements in the Suites are of this character. Bach’s melody, then, bears the unmistakable stamp of originality. And so does his passage work, as it is called. Such novelty, originality, and brilliancy are not found in any other composer. Examples are to be found in all Bach’s Clavier works. But the most striking and original are in the _Great Variations,_(151) in the first Part of the _Clavierübung,_(152) in the _English Suites,_(153) and the _Chromatic Fantasia._(154) In the last particularly Bach’s fertility impresses us. The greater part of its passage work is in the form of harmonic arpeggios whose richness and originality match the chords they represent. In order to realise the care and skill Bach expended on his melody and harmony, and how he put the very best of his genius into his work, I need only instance his efforts to construct a composition incapable of being harmonised with another melodic part. In his day it was regarded as imperative to perfect the harmonic structure of part-writing. Consequently the composer was careful to complete his chords and leave no door open for another part. So far the rule had been followed more or less closely in music for two, three, and four parts, and Bach observed it in such cases. But he applied it also to compositions consisting of a single part, and to a deliberate experiment in this form we owe the six Violin and the six Violoncello Solo Suites,(155) which have no accompaniment and do not require one. So remarkable is Bach’s skill that the solo instrument actually produces all the notes required for complete harmony, rendering a second part unnecessary and even impossible.