Its great water-front, at which vessels of burden may lie to an extent (as is stated by the Harbor Commissioners) of fifty miles--every foot of which is, or may be directly connected with our railroads. There is not a wharf along the whole circuit which may not, without great expense, be made available for the export of the productions of the country, brought by the railroad car to the side of the ship, which shall convey it to the freight market. If we can secure to Boston a fair share of the export trade of the country, the import and domestic trade will follow, and we ensure the building of a city within the limits of my friend's annexation project, that will equal the greatest city of the continent. THE EFFECT ON THE STATE OF MAKING BOSTON AN EXPORTING CITY. It is hardly necessary to allude to the close connection which Boston holds to Massachusetts. One-third of the population of the State and one-half its valuation are combined within a circle of five miles from this building. The prosperity of Boston is inseparable from the prosperity of Massachusetts. The recent calamity of Boston was felt throughout the limits of the State. But the great benefit to the State from making Boston an exporting city is not the prosperity of the city itself. It grows out of the condition which alone can make Boston a city of export for the productions of the country. This can only result from a reduction in the transportation tax which will make such productions relatively cheaper in Boston than in New York. In the profits of such a result the remotest corner of the State will directly share. Transportation cannot be reduced to Boston without a corresponding reduction upon every line of railroad leading to or from this city. It was with a hope of such a result that the State entered upon the project of building the Hoosac Tunnel, and it rests with us to say, now that this great enterprise is so near completion, whether this hope can be realized. THE HOOSAC TUNNEL. It is needless to explain at any length what the Hoosac Tunnel is. There can be no member of this board who does not know that we in Massachusetts are separated from the West by a mountain barrier extending from near Long Island Sound to near the Canada line. This barrier must be passed to bring us into connection with the West.