Mr. Lincoln and the Republican Party resorted to arms not intending the slightest alteration in the constitutional status of slavery. But the presence of Union armies on slave soil led to new and puzzling questions. What should be done with slaves escaping to the Union lines? Generals Buell and Hooker authorized slave-holders to search their camps for runaway slaves. Halleck gave orders to drive them out of his lines. Butler, alleging that since slaves helped "the rebels" by constructing fortifications they were contraband of war, refused to return those fleeing into his camp. Congress moved up to this position in August, 1861, declaring that slaves used for hostile purposes should be confiscated. But when Fremont and Hunter issued orders freeing slaves in their military districts, President Lincoln felt obliged to countermand them, fearing the effect upon slave States that were still loyal. As the war went on the conviction grew that peace would never be safe or permanent if slavery remained, and that the suppression of the Rebellion was postponed, jeopardized, and made costlier by every hour of slavery's life. Slaves raised crops, did camp work, and built fortifications, releasing so many more whites for service in hostile ranks, instead of doing all this, and fighting, even, for the Union. It is interesting to trace the growth of emancipation sentiment during 1862 as it is reflected in congressional legislation. In March army officers were forbidden to return fugitive slaves. In April slavery was abolished in the District of Columbia, with compensation to owners. At the same time Congress adopted a pet scheme of Mr. Lincoln's, offering compensation to any State that would free its slaves. None accepted. There were about 3,000 slaves in the District. Upon the day of their emancipation they assembled in churches and gave thanks to God. In June slavery in the Territories--that bone of contention through so many years--was forever prohibited. In July an act was passed freeing rebels' slaves coming under the Government's protection, and authorizing the use of negro soldiers. Already President Lincoln was meditating universal emancipation. September 22d the friends of liberty were made glad by a preliminary proclamation, announcing the President's intention to free the slaves on January 1, 1863, should rebellion then continue to exist. It is said that Mr. Lincoln would have given this notice earlier but for the gloomy state of military affairs. The day comes. The proclamation goes forth that all persons held as slaves in the rebellious sections "are and henceforth shall be free." The blot which had so long stained our national banner was wiped away. The Constitution of course does not expressly authorize such an act by the President, but Mr. Lincoln defended it as a "necessary war measure," "warranted by the Constitution upon military necessity."