It has been remarked more than once that Bach, throughout his life, devoted much thought to the improvement of his compositions. I have had frequent occasion to compare the original and subsequent texts of his works, and confess to have experienced both surprise and pleasure in observing his care to improve whatever he thought faulty, to make good better, and better perfect. Nothing is more instructive than a collation of this kind, whether to the experienced musician or the instructed amateur. I should like to see a supplement to the complete edition of Bach’s works showing these variant readings.(323) The collation would be in the highest degree instructive, and to attempt it is as appropriate to the works of the composer, a poet in sound, as to those of the poet in words. In Bach’s early texts he often repeats a phrase to other words with some melodic variety, in a lower or even in the same octave. In his riper experience he could not tolerate such poverty of workmanship, and cut out these passages remorselessly, without regard for the number and quality of the persons who had approved them in their original state. There occur to me two good examples of this, the C major and C sharp minor Preludes in the first part of the _Well-tempered Clavier._ Bach revised them so drastically as to cut them down by one-half, sacrificing passages that he thought redundant.(324) In other places Bach tends to be over-concise; he expresses an idea, but does not fully develop it. The best illustration that occurs to me is the D minor Prelude in the second part of the _Well-tempered Clavier._ I possess several texts of it. In the oldest the first transposition of the theme in the Bass and several other details essential to a complete development of the idea are wanting. A second MS. gives the theme to the Bass wherever the latter is in a key nearly related to that of the tonic. In a third MS. these addenda are developed more fully and are joined more skilfully. But melodic details are present of doubtful relevance to the rest of the composition. In a fourth MS. these disappear or are amended, so that, as we have it, the Prelude stands as one of the most beautiful and least faulty in the _Well-tempered Clavier._ Many people, no doubt, preferred the movement in its original form. But Bach was not a man to be influenced by approbation or criticism. He went on correcting until he satisfied himself. In the early part of the seventeenth century it was the fashion in instrumental music to overload single notes with ornaments and add florid runs. Lately it has become the fashion to do so in vocal music as well. That Bach shared this disposition may be inferred from certain pieces that he wrote in this style. An instance is the Prelude in E minor in the first part of the _Well-tempered Clavier._ But he soon returned to his natural better taste, and altered the movement to the form in which it is engraved.(325)