I have as yet said nothing on the telegraph as a mighty aid to national defence. Its importance in this respect is so obvious, that I need not dilate. The importance generally to the government and to the country, of a _perfect_ telegraphic system, can scarcely be estimated by the short distance already established between Baltimore and Washington. But when all that transpires of public interest at New Orleans, at St. Louis, at Pittsburgh, at Cincinnati, at Buffalo, at Utica, at Albany, at Portland, at Portsmouth, at Boston, at New York, at Philadelphia, at Baltimore, at Washington, at Norfolk, at Richmond, at Charleston, at Savannah, and at all desired intermediate points, shall be _simultaneously_ known in each and all these places together—when all the agents of the government, in every part of the country, are in instantaneous communication with head-quarters—when the several departments can at once learn the actual existing condition of their remotest agencies, and transmit at the moment their necessary orders to meet any exigency—then will some estimates be formed both of the powers and advantages of the magnetic telegraph. Should the government be now disposed to possess the right of the proprietors, by giving them a fair consideration, I shall be ready to treat with them on the terms of transfer. For myself, I should prefer that the government should possess the invention, although the pecuniary interests of the proprietors induce them to lean towards arrangements with private companies. In closing this report, I would take the opportunity of favorably mentioning to the department the efficient attention to the duties of their respective stations given by my assistants, Alfred Vail and H. J. Rogers, esqrs.—the former directing the correspondence at the Washington terminus, and the latter at the Baltimore terminus. Very respectfully, sir, your obedient servant, SAM. F. B. MORSE, _Superintendent of Electro Magnetic Telegraphs for the United States_. To the Hon. GEO. M. BIBB, _Secretary of the Treasury_. _Magnetic Telegraph from Baltimore to New York, March 3, 1845._ Mr. CHAPPELL, from the Committee of Ways and Means, made the following Report. The Committee of Ways and Means, to whom was referred a resolution instructing said committee to inquire into the expediency of reporting a bill to continue the Electro Magnetic Telegraph from Baltimore to New York, by way of Philadelphia, beg leave to submit the following report: