WILLIAM H. SEWARD. The stranger who enters the hall of the United States Senate and casts his eye over the array of senators, will be not a little surprised, possibly somewhat amused, when William H. Seward is pointed out to him. Accustomed to think of Mr. Seward as one of the greatest men in the country, a first-class statesman, as well as orator--for he has _read_, not _heard_, his numberless speeches upon the subjects of the day--he expected to find a gentleman of imposing aspect, to discover the impressive appearance which awes the stranger, or the audience. But, instead of this, he finds a quiet man, sitting in his seat, listening with imperturbable calmness to every senator who chooses to speak, however dry, however provoking, however stupid. For Mr. Seward is well known to be _the best listener_ in the Senate. This arises from his rigid politeness, if we may use the phrase, which will not allow him to refuse his ear and eye to any man who chooses to speak. There he sits, leaning back in his chair, a slender man, of average height, clad in simple black, with a singular face, grey eyes, grey hair, Roman nose, a second Wellington, ever in repose. Who ever saw William H. Seward excited? He is never to be provoked by friend or enemy, and is either devoid of all sensibility, or has a spirit which can triumph over, soar above, the common infirmities of poor human nature. We have seen Mr. Seward on two very trying occasions. One, when Mr. Hale, his friend and seat-mate, thought it his duty to severely criticise his vote on the army bill (this was in the winter of 1857-8), and in which criticism he was very personal. Mr. Seward sat composedly in his seat during the painful review of his brother senator, and rose to reply as pleasantly and as quietly as he ever did in his life. On another occasion, when the Senate sat late in the night on the Cuban bill--last spring--Mr. Toombs made a fierce, and we must say disgraceful attack upon Mr. Seward, calling him, among other names, "a tuppenny demagogue." During the entire harangue by the Georgian senator, Mr. Seward twirled his spectacles, unconsciously, and in his reply was slow, freezingly cold, and never for a moment addressed or looked at Mr. Toombs. These facts show that Mr. Seward purposely refuses in public to allow himself to be angered by personalities or to offer there personalities. He guards constantly against the temptation to offend in this particular. He has often been accused by ardent Republicans of lacking courage, physical courage, and that he did not reply to the attacks of his southern enemies with sufficient spirit. It is a mistake to ascribe this conduct of Mr. Seward to cowardice. It is the result of deliberate thought in him--and if it is mistaken policy, then of course it is to be set down as a blunder, not a vice.