A full and authentic edition of Mozart's Letters ought to require no special apology; for, though their essential substance has already been made known by quotations from biographies by Nissen, Jahn, and myself, taken from the originals, still in these three works the letters are necessarily not only very imperfectly given, but in some parts so fragmentary, that the peculiar charm of this correspondence—namely, the familiar and confidential mood in which it was written at the time—is entirely destroyed. It was only possible to restore, and to enable others to enjoy this charm—a charm so novel, even to those already conversant with Mozart's life, that the most familiar incidents acquire fresh zest from it—by an ungarbled edition of these letters. This is what I now offer, feeling convinced that it will be welcome not only to the mass of Mozart's admirers, but also to professional musicians; for in them alone is strikingly set forth how Mozart lived and labored, enjoyed and suffered, and this with a degree of vivid and graphic reality which no biography, however complete, could ever succeed in giving.