It is not difficult to distinguish with exactitude those of Bach’s early compositions which are of the first excellence; for he has been at pains to give us the clue. As he did not publish his first work until he was about forty years old (223) we are justified in assuming the merit of what, at so mature an age, he thought worthy to put into print, and in concluding generally that all his engraved works are of first-rate merit.(224) With respect to his unpublished compositions, and they are by far the most numerous, we must in order to distinguish their merit rely partly on a critical examination of their texts, partly on Bach’s own judgment. Like all great composers, he was continually working on his compositions with a view to making them still more finished. Indeed, he actually attempted to improve some of them that were already perfect. Any that were susceptible of improvement he improved, even those already engraved. Such is the origin of the variant readings of his works found in older and more recent texts. By constantly retouching his compositions Bach aimed at making them indisputable masterpieces. In this category I place most of what he wrote before the year 1725, as I show in detail in the following catalogue. A great many compositions subsequent to 1725, which for reasons easily understood are still in MS., bear too evidently the stamp of perfection to leave us in doubt whether to class them as early essays or as the finished work of an accomplished master. The following are those of Bach’s works which have been engraved: