"The orchestra commenced with Rossini's Overture to "William Tell"--perhaps the finest piece of instrumental picture music since Haydn's Creation and the Pastoral Symphony of Beethoven. Its fresh and vivid coloring, its atmospheric changes, its smart Alpine vigor and heroic ensemble, were made as present and as real as any sixty instruments could make them. Exquisitely did those three violoncellos sketch the first scene of soft, cool sunset on the unruffled lake; the mellow Corno Anglaise, male partner to the oboe, sweetly woke the flute-like mountain echoes; the low moan and whistle of the storm rose life like in the crescendo of the violins, and as it died away the startling quick-step of liberty leaped strong and simultaneous from such a tutti as we have hardly heard from any orchestra. We can believe that Mr. Benedict was quite sincere in telling them he had not conducted a better orchestra in Europe. The other Overture to Masaniello was also splendidly played, but the composition is, to our taste, too hackneyed to fill out the programme of a Jenny Lind before the largest audience in the world. The accompaniments to the singing were usually given with sympathetic precision, and subdued shading or vigorous seconding, as the case required. We cannot speak too well of M. Benedict's control of his forces. "The second piece was the Viravviso ("As I View Now") from La Somnambula, delivered in the richest and most vibrating barytone that WE Americans have heard, by Sig. Belletti. Now that we have heard him from a nearer position, we have not a doubt left of his superiority in voice, style, execution to all our Italian favorites of the same register hitherto. He absolutely glorified the cavatina which rapidly grew commonplace with Brough, and had but half recovered even in the hands of the worthy Italian artists who have since sung it on the stage for us. His crowning achievement last night, however, was the actual singing of a Tarentella by Rossini--a kind of movement which we have hitherto heard only from instruments--a whirling, spinning, delirious, top-like movement in which the singer seems galvanized and tyrannized by one too happy and all-mastering idea in spite of himself. The audience too, in spite of themselves, were sucked into its whirling ecstacy, and it was imperatively encored. In Mozart's Non piu Andrai the chaster prototype of Rossini's Largo al factotum, his vocalization was elastic, spirited and elegant, but the effect of such a piece was necessarily lost upon the outer circles of so vast an auditory. "For other variety there was a brilliant show duett on themes from La Somnambula for piano and violin by Messrs. Benedict and Noll, and a solo on the pianoforte by that most promising young artist, Hoffman. For this he chose De Meyer's fantasy on Semiramide, decidedly of the modern monster school of pianoforte composition, though quite a vigorous, graceful and redeeming specimen thereof.