WILLIAM H. SEWARD, it seems to be settled, will be Secretary of State, in the Cabinet of President LINCOLN. The eminent fitness of the appointment, has been on all hands recognized, and the doubt has been whether Mr. SEWARD would leave the Senate in which he has proved himself a worthy successor to the best and ablest of the patriots who have honored that body, for any other public service; while many have believed he would choose rather to represent his country as its Minister at the Court of St. James, if he should refuse the re-election as Senator, which his State so cordially tenders.

Mr. SEWARD will leave no peer behind him in the Senate of the United States. During the twelve years he has served in that body, he has been faithful to his constituents and to the convictions which endeared him to them. Received at first with a hauteur that would have crushed a weaker man; ostracized from society, and made the target of the contumely and meanness which the representatives of slavery so long directed against the champions of free labor, he has survived to find all this changed. Never allowing himself to be drawn into personal disputes, he has done much to elevate the tone of Senatorial discussion. Although in the minority in the Senate, the present Administration has consulted him upon all foreign affairs, and has relied upon him for the support of measures essential to the Republic. Grappling the topics that come up for his consideration, not with a view to mere word-battles in the Senate, but to their broad and exhaustive elucidation, he has discussed principles rather than measures, has uttered general truths that will live, rather than fitted theory to the exigency of circumstances. Appealing to the “higher law,” as a test of enactments and constitutions, he has proved true to the cardinal principle of the Republic, and has combatted with a fidelity that will not be forgotten, the grave heresies that have assailed and threatened our clearest institutions. Who, after him, in the Senate, shall represent so well the love of freedom, combined with the love of the Union, that inspires the North? Who shall discuss so temperately, so exhaustively, with such masterly generalizations, with such preference of principle over temporary success, the great subjects which must agitate a free people? Who, himself a resident of a rural town, shall so faithfully represent the grand commercial interests of the metropolis, and shall, while proving true to its conscience, confer by his dignity and services so much honor upon the State[?] Different from the great statesmen with whose career[s] his own was in his first term connected, he bears the mantle that fell from their shoulders, not ungracefully, and easily chief among his peers, has maintained the character of the Senate. Having succeeded so well there, he will leave that body with the regret of many who, not agreeing with his opinions, have by his persistent fidelity and distinguished ability been drawn into admiration of his Senatorial career.

Mr. SEWARD has many of the peculiar qualifications needed in the State Department. By his position on the Senate Committee of foreign affairs, he has become versed in the details of our relations with all the nations of the world. No one of our statesmen commands to such a degree the confidence of England and France, and indeed of Christendom. If his sentiments have met with objection in some parts of his own country, they have been accepted abroad as the faithful utterance of Republican principles, and he has become identified in other lands with them. Never suffering mere personal feeling to interfere with public duty, never allowing passion to weigh down principle, persistent in demanding and in obtaining the right, his temperament and habits will render his distinguished ability and long national experience of the greatest service to the country.

Nor does any man more entirely command the confidence of the people of the United States, regardless of party. The nomination of another for President by his party, removed something of the asperity which would have assailed him as a candidate. His opponents who declared he ought to have been nominated for President, must welcome him as Secretary of State. His friends who stood by him at Chicago, will rejoice that the new Administration is to have the benefit of his services. And every true friend of ABRAHAM LINCOLN, who wishes for him a successful career for the sake of the country, will see a good harbinger in the selection of Mr. SEWARD.

WM. H. SEWARD, EDWARD BATES, SIMON CAMERON, SALMON P. CHASE, are names that give security that Mr. LINCOLN’s Administration will be distinguished for its ability, will be strong enough to meet any crisis which human wisdom may face, and will be true to the principles in behalf of which the national scepter is passed into its hands.