The evening of Saturday, Aug. 21st, will long be remembered by the habitués of the Opera. From exclusive sources (which have been opened to us at a very considerable expense) we are enabled to communicate—malheureusement—that with the close of the saison de 1841, the corps opératique loses one of its most brilliant ornaments. That memorable epocha was chosen by Rubini for making a graceful congé to a fashionable audience, amidst an abundance of tears—shed in the choicest Italian—and showers of bouquets. The subjects chosen for representation were apropos in the extreme; all being of a triste character, namely, the atta terzo of “Marino Faliero,” the finale of “Lucia di Lammermoor,” and the last parte of “La Sonnambula:” these were the chosen vehicles for Rubini’s soirée d’adieu. As this tenor primissimo has, in a professional regarde, disappeared from amongst us—as the last echoes of his voix magnifique have died away—as he has made a final exit from the public plafond to the coulisses of private life—we deem it due to future historians of the Italian Opera de Londres, to record our admiration, our opinions, and our regrets for this great artiste. Signor Rubini is in stature what might be denominated juste milieu; his taille is graceful, his figure pleasing, his eyes full of expression, his hair bushy: his comport upon the stage, when not excited by passion, is full of verve and brusquerie, but in passages which the Maestro has marked “con passione” nothing can exceed the elegance of his attitudes, and the pleasing dignity of his gestures. After, par exemple, the recitativi, what a pretty empressement he gave (alas! that we must now speak in the past tense!) to the tonic or key-note, by locking his arms in each other over his poitrine—by that after expansion of them—that clever alto movement of the toes—that apparent embracing of the fumes des lampes—how touching! Then, while the sinfonia of the andante was in progress, how gracefully he turned son dos to the delighted auditors, and made an interesting promenade au fond, always contriving to get his finely-arched nose over the lumières at the precise point of time (we speak in a musical sense) where the word “voce” is marked in the score. His pantomime to the allegri was no less captivating; but it was in the stretta that his beauty of action was most exquisitely apparent; there, worked up by an elaborate crescendo (the motivo of which is always, in the Italian school, a simple progression of the diatonic scale), the furor with which this cantratice hurried his hands into the thick clumps of his picturesque perruque, and seemed to tear its cheveux out by the roots (without, however, disturbing the celebrated side-parting a single hair)—the vigour with which he beat his breast—his final expansion of arms, elevation of toes, and the impressive frappe of his right foot upon the stage immediately before disappearing behind the coulisses—must be fresh in the souvenir of our dilettanti readers.