The recent practical improvements in the art of printing, the telegraph and the railway, have furnished to mankind the means of reaching safe conclusions in all matters of importance, including biography and history, with a celerity and certainty which to former ages were unknown. In these five and twenty years, since the death of Mr. Lincoln, there has been a wonderful exposition of the events and circumstances of the stupendous contest in which he was the leading figure, and all that knowledge is now consummated on the pages of Nicolay and Hay's complete and trustworthy history. Of the minor incidents of Mr. Lincoln's career, time and research will disclose many facts not now known, which may lend coloring to a character whose main features, however, cannot be changed by time nor criticism. The nature of Mr. Lincoln's services we can comprehend, but their value will be more clearly realized and more highly appreciated by posterity. As to the nature of those services the judgment of his own generation is final--it can never be reversed. Indeed, it may be asserted of historical personages generally, that the judgment of contemporaries is never reversed. Attempts have been made to reverse the judgment of contemporaries, in the cases of Judas Iscariot, of Henry the Eighth, and of Shakespeare, and I venture the assertion that all these attempts have failed, most signally. In our own country there have been no reversals. Modifications of opinions there have been--growth in some cases, decrease in others, but absolute change in none. The country has grown towards Hamilton and away from Jefferson. They are, however, as they were at the beginning of the last century, the representatives of antagonistic ideas in government, but their common patriotism is as yet unchallenged. It is the fate of those who take an active part in public affairs, to be misjudged during their lives, but death softens the asperities of political and religious controversies and tempers the judgment of those who survive. Franklin, Washington, Jackson, Clay and Webster, are to this generation what they were to the survivors of the respective generations to which they belonged. Mr. Calhoun has suffered by the attempt to make a practical application of his ideas of government, but the nature and dangerous character of those ideas were as fully understood at the time of his death as they are at the present moment.