Boston has been in a flutter of agitation and excitement to-day; for, truth to say, Boston herself has not been over sanguine as to the success of the Jubilee. It is probable that not a person in the city has regarded the experiment in the light of an unquestioned success, except Mr. Gilmore, in whose fertile brain the Jubilee was conceived, and by whom it has been pushed forward, in the face of obstacles, to a successful birth. When Mr. Gilmore offered the Jubilee to New York, the Manhattanites laughed at him, and gently insinuated that he had gone clean daft, whereupon Mr. Gilmore took his embryonic Jubilee to Boston, and, undaunted by obstacles, and unannoyed by the gibes and jeers of the faithless, he worked in season and out of season, put this wheel and that wheel together, got this man and that man interested in it, melted even the adamantine hearts of the musicians themselves, and at last got his project so far advanced that it became a matter of city pride to put the municipal shoulder to the wheel and help Gilmore out with his mammoth undertaking. And Boston did help him right royally. Once provided with the ducats and with the collaterals, which guaranteed him financial safety, the foundations of the enterprise were laid, and the superstructure grew rapidly. Singers and instruments, big singers and little singers, big fiddles and little fiddles, poured in as fast and as thick as the dogs and cats in Beard's picture. I myself saw, riding on a boat of Commodore Fisk's, from New York to Fall River, en route to the Jubilee, sixty double basses ranged along on the deck, like coffins swathed in green bags, and to-day I saw them again manipulated in the vast orchestra, to show that I do not lie.

The material was, at last, all in his hands, and the material was composed of one thousand instruments—a big organ, ten thousand singers, a Coliseum, and sundry properties by way of appendices, such as a battery of artillery, church bells, and anvils. And the question immediately arose:

What will he do with them?

This is the question which has agitated Boston to-day, from the harbor to the Back Bay, and from Bunker Hill to Jamaica Plain. When Boston woke up this morning, notwithstanding her doubts, she dressed herself in festal garments of streamers, flags and bunting, to do honor to the occasion, and to properly impress the strangers within her borders with the fact that she was out for a holiday, and was bound to enjoy herself. And there were strangers enough within her borders. Every other man you met upon the narrow sidewalks was a carpet-bagger, and every other woman had a roll of music in her hands. Band musicians in all sorts of uniforms, carrying all sorts of odd-looking boxes, met you and jostled you at every turn, for it is impossible for two people to pass each other upon a Boston sidewalk, especially if one has a box or a carpet-bag in his hands. Every train and every boat which has arrived to-day was loaded down with musical freight, and all the morning they filed down Boylston street to the Coliseum, in water-proof cloaks with their rolls of music. The hotels are filled with them. The boarding houses are full, both in the city and in the suburbs, and even some of the public halls have been provided with cots, to accommodate the melodious strangers, who have come here to lift up their voices in the grand chorus.

And it is a grand chorus. In 1836, Mendelssohn, the great master, led 536 performers, and ten years later led his own "Elijah," with a chorus of 700 before him. In 1862 a chorus of 4,000 voices sang together at the Crystal Palace in London; and last year Costa led 4,500 in the same building. It was considered a great event—an episode in the history of music. Julien, that eccentric little conductor, conceived the idea of increasing upon this number, but the very magnitude of his operations turned his brain, and he died in a mad-house—his disordered mind, even in his dying moments, being occupied with an imaginary orchestra. It has been left for Mr. Gilmore to eclipse them all. What was some time a problem is now a fixed fact; and the annals of music can show no grander triumph than that which this daring, hard working man has achieved this day. When Mr. Gilmore's baton closed the final chord of the massive Martin Luther choral, he had done something which was worth living for. He had a right to be proud of his work.

The Coliseum in which the Jubilee is given, is upon the made lands of the Back Bay. Upon its site young Boston has fished in the summer, and skated in the winter. When Boston had filled out to the water's edge, it did what Canute could not do. It commenced to drive back the sea, and each step that the sea receded was filled up and built upon. Aristocracy turned its eyes thitherward, and went there to build its free-stone fronts, and made it the handsomest part of the city. The Coliseum is on the newest of this land, where it has not yet been divided off into lots. Its immediate surroundings, therefore, are not very attractive. The exterior of the building is not remarkably beautiful, and the fine Natural History rooms, and other elegant buildings near by, provoke architectural comparisons not particularly favorable to it. It has a cheerful, pleasant appearance, however, and derives a certain sort of brilliancy from the little flags of divers colors which flutter in the breeze from every salient point. The hucksters and venders of notions, who have improved the occasion to turn an honest or dishonest penny, as the case may be, have not improved the ensemble with their scores of board shanties and canvas tents, which have been dumped down upon the crude ground in every direction. Their name is almost literally legion. There are venders of ice creams, which are mushy and sloppy; of soda water with gaudily colored syrups; of innocent vegetable beer, for the hard hand of the law forbids the sale of anything stronger; of domestic cigars compounded of innocuous herbs; of oranges, and pop corn, and bananas, and photographs, and fans. At this shanty you may get revolving heels placed upon your boots, and at that one you can get key tags stamped. Here the wild men of Borneo are delighting a crowd, and there you may see a two-headed monkey cheap. Blind men are selling ballads. Small girls are vending hot roasted peanuts. Here is a shooting gallery, and there a fandango. The old buxom Irish women of the common, who have been accustomed to drowse away their days under the elms, have suddenly become imbued with the enterprise of the hour, and are driving sharp bargains on the Back Bay in oranges and candy, and puff away at their dhudeens with an air of self congratulation.

Notwithstanding these drawbacks, however, the Coliseum admirably answers the purposes for which it was built. It is large enough to accommodate all who will go. Its ventilation is excellent; its acoustic properties good, and its conveniences perfect as they can be. The interior is beautifully decorated with bunting, streamers, flags, and various paintings and devices. The sub-rooms, especially the reception room, are exquisitely adapted to the purposes for which they were designed. The latter room, this morning, presented a perfect wilderness of flowers, and its walls were hung with elegant paintings. Its seating capacity is, I should judge, between thirty and forty thousand, exclusive of the chorus and orchestra. The roughness and blank appearance of unfinished wood-work, has been concealed by drapery and bunting very gracefully arranged, and from one end of the Coliseum to the other, the eye is attracted by the brightest of colors.

It is now my task to describe to you the opening concert, and I freely confess my inability to do so. As I write you, the deep diapason of that mighty organ, the surging waves of harmony from the largest orchestra and the marvelous sublimity of the largest chorus the world has ever known, are still in my ears, and it seems to me that I can find no words to describe it. I can feel it, but I cannot make you feel it with poor words. It almost seems a profanation to attempt it. To see that multitude alone is electrifying. It makes your blood stir within you, to look upon that great sea of faces stretching off into the distance, and to know that one man holds them in his hand, and with his little baton guides and sways them at his will. One man in that vast throng is only as one drop in the sea—one grain of sand upon the shore. His voice is indistinguishable, but the aggregate, you feel within you, will be as the on-coming of the mighty storm.

Picture to yourself the scene. Immediately before you is the orchestra, one thousand strong, occupying the level platform. The brasses are at the rear, as you may easily perceive, by a strip as of gold, which runs through the sombre black, and right between them is a huge bass drum, looming up like the wheel of a steamboat. From this level platform, on three sides, rises an amphitheatre, which holds the great chorus, ten thousand strong. The sopranos are on the left, the altos on the right, and the tenors and bassos in the centre, and up from their midst rise the open pipes of the great organ, the player of which sits facing the conductor, at some distance from the organ, communicating with him by means of speaking tubes. Sub-conductors are also located near each of the choral parts, who convey the instructions of the main conductors. Just at the right of the conductor there is an electrical battery which communicates with a section of artillery at a distance. The instrumental performers are arranged in the orchestra. The first, the chorus orchestra, is made up as follows:

Stringed.Wind.
First Violins115Flutes8
Second Violins100Clarionets8
Violoncellos65Oboes8
Violas65Bassoons8
Double Basses85Horns12
——Trumpets8
430Trombones9
74Tubas3
——Drums10
Total,504 ——
74