The correspondent of the “Allg. Mus. Zeit.,” under date of April 2, writes: “Beethoven has again produced his opera ‘Fidelio’ on the stage with many alterations and abbreviations. An entire act has been omitted, but the piece has benefited and pleased better.” On Thursday, the 10th, it was given again. The following letters from Beethoven to Sebastian Meier, referring to this performance, complain of “many blunders” in the choruses, ask for new rehearsals, and say: Please ask Mr. Seyfried to conduct my opera to-day, I want to look at and hear it from a distance, thus at least my patience will not be so greatly tried as if I were to hear my music bungled close at hand! I cannot think otherwise than that it is done purposely. I will say nothing about the wind-instruments, but that all ~pp~, ~crescendo~, all ~decres.~ and all ~forte~, ~ff~, have been elided from my opera; at any rate they are not played. All delight in composing departs when one hears it (one’s music) played ~thus~! Seyfried’s autograph record of all performances in the Theater-an-der-Wien, through a long series of years, gives “Sargino” instead of “Fidelio,” for Saturday the 12th--and “Agnes Bernauer” for the Sunday and Monday following. That this old, well-known drama was so repeated affords a strong presumption that an opera--we think “Fidelio”--was withdrawn “because obstacles had suddenly appeared” after it was too late to supply its place with another. At all events, the production of “Fidelio” on Thursday, April 10th, was the last; for which fact, two explanations are given--that in Breuning’s letter, and one by Röckel in his letter to the author. Breuning attributes it to the composer’s enemies--to a cabal, to “several persons whom Beethoven had offended, especially at the second representation”; Röckel, to Beethoven’s own imprudence and folly. Breuning, a Secretary in the War Office, could have had little leisure for theatrical matters in those melancholy days during the French occupation and immediately after; it is a cause of surprise, that he found time for the revision of the “Fidelio” text; his record, therefore, could hardly have been made except upon the representations of his friend--the last man to admit that he was in fault. But Röckel was behind the scenes in a double sense: he sang the part of ~Florestan~ and while Beethoven’s “friends were, most of them, married men, not able to walk and dine out with him (as he writes) like myself, another bachelor, to whom he took a fancy--I could call upon him in the morning and in fine weather stroll and dine with him in the country.” Breuning and Röckel are alike men of unimpeachable veracity; but the latter speaks from personal knowledge and observation.