On January 1, 1863, when the President issued the Proclamation of Emancipation, he stepped to the uttermost boundary of his authority in the direction of the abolition of slavery. Indeed a large proportion of the people believed that he had trespassed beyond that boundary; and among the defenders of the measure there were many who felt bound to maintain it as a legitimate exercise of the war power, while in their inmost souls they thought that its real basis of justification lay in its intrinsic righteousness. Perhaps the President himself was somewhat of this way of thinking. He once said: "I felt that measure, otherwise unconstitutional, might become lawful by becoming indispensable to the preservation of the Constitution through the preservation of the Union.... I was, in my best judgment, driven to the alternative of either surrendering the Union, and with it the Constitution, or of laying strong hand upon the colored element." Time, however, proved that the act had in fact the character which Mr. Lincoln attributed to it as properly a war measure. It attracted the enlistment of negroes, chiefly Southern negroes, in the army; and though to the end of the war the fighting value of negro troops was regarded as questionable, yet they were certainly available for garrisons and for many duties which would otherwise have absorbed great numbers of white soldiers. Thus, as the President said, the question became calculable mathematically, like horse-power in a mechanical problem. The force of able-bodied Southern negroes soon reached 200,000, of whom most were in the regular military service, and the rest were laborers with the armies. "We have the men," said Mr. Lincoln, "and we could not have had them without the measure." Take these men from us, "and put them in the battlefield or cornfield against us, and we should be compelled to abandon the war in three weeks."