At the close of February, Lee, who realises that his weakened lines cannot much longer be maintained, proposes to Grant terms of adjustment. Grant replies that his duties are purely military and that he has no authority to discuss any political relations. On the first of April, the right wing of Lee's army is overwhelmed and driven back by Sheridan at Five Forks, and on the day following Richmond is evacuated by the rear-guard of Lee's army. The defence of Richmond during the long years of the War (a defence which was carried on chiefly from the entrenchments of Petersburg), by the skill of the engineers and by the patient courage of the troops, had been magnificent. It must always take a high rank in the history of war operations. The skilful use made of positions of natural strength, the high skill shown in the construction of works to meet first one emergency and then another, the economic distribution of constantly diminishing resources, the clever disposition of forces, (which during the last year were being steadily reduced from month to month), in such fashion that at the point of probable contact there seemed to be always men enough to make good the defence, these things were evidence of the military skill, the ingenuity, the resourcefulness, and the enduring courage of the leaders. The skill and character of Lee and his associates would however of course have been in vain and the lines would have been broken not in 1865, but in 1863 or in 1862, if it had not been for the magnificent patience and heroism of the rank and file that fought in the grey uniform under the Stars and Bars and whose fighting during the last of those months was done in tattered uniforms and with a ration less by from one quarter to one half than that which had been accepted as normal.