On the 28th of February, Beethoven sent his friend Mähler an invitation to a concert. Mähler accepted the invitation and received a ticket “extra-ordinaire,” signed “B^r. de Neuwirth,” admitting him free to three midday concerts on Thursdays, February 28, March 14 and 28. Beethoven’s elasticity of temperament therefore was doing him good service in enabling him to recover from the crushing blow of the preceding year; he was now able not only to find diversion and amusement in society, the theatre and the concertroom, but the spirit of composition was again awakened. In three weeks--March 3rd to the 26th--he produced the glorious B-flat Trio, Op. 97, which had been sketched in 1810. There were now, or soon to be, in the hands of Breitkopf and Härtel’s engravers the Pianoforte Concerto, Op. 73, the Fantasia, Op. 80, the Sonate “Les Adieux,” Op. 81a, the Ariettes and Songs, Op. 82 and 83, and the “Christus am Ölberg.” The revision of these works for the press, with the correction of the proofs and his duties to the Archduke, are all the professional labors of Beethoven in these months of which we find any trace. Hence, that high appreciation of his greatness, which induced his admirers and friends even then to attach such value to the most trivial written communications from him as to secure their preservation, now does us excellent service; for--the dates of the Trio excepted--his correspondence furnishes the only materials for the history of the first half of this year. To this we turn. [Sidenote: THE PIANOFORTE TRIO IN B-FLAT] There is a note, which may be dated about the end of March, apologizing to the Archduke for his absence, on the ground of having been for two weeks again with his “tormenting headache.” “During the festivities for the Princess of Baden (March 5-12), and because of the sore finger of Your Imp. Highness,” he adds, “I began to work somewhat industriously, of which, among other things, a new Trio for the piano is a fruit.” Soon after he sends the new Trio to the Archduke to have it copied, “but only in your palace, as otherwise one is never safe from theft.” He proceeds thus: I am improving and in a few days I shall again have the honor to wait upon you for the purpose of making up for lost time. I am always anxiously concerned when I cannot be as zealously and as often as I should wish with Your Imperial Highness. It is surely true when I say that it causes me much suffering, but I am not likely to have so bad an attack again soon. Keep me graciously in your memory. Times will come when I shall show you two and threefold that I am worthy of it.