In the early hours of the morning the hills echoed with the firing of artillery. Porter made an infantry attack in the forenoon, and was pressed back in great confusion by superior numbers. One attack after another followed. In the afternoon a large part of the Union army made a desperate attack on the Confederate left, under Jackson, but their lines were swept by an enfilading fire from the batteries of Longstreet. Ghastly gaps were cut in the Federal ranks, and they fell back, but rallied again and again to the attack, each time to be mowed down by Longstreet's artillery. At length Longstreet's whole line rushed forward and the Union front began to waver. General Lee ordered a general advance. Pope retreated across Bull Run, leaving several thousand prisoners in the hands of the Confederates. Pope led his army back to the entrenchments at Washington, while Jackson and Stuart followed close on the heels of his army, and he was compelled to make several stands in battle on his retreat, in one of which General Kearny was killed. BATTLE OF ANTIETAM After Pope's disastrous defeat at Second Bull Run he begged to be relieved of the command of the army. He gave as one of the causes of his defeat that General Fitz John Porter had disobeyed orders. General Porter's explanation to the Court Marshal failed to convince it and he was dismissed from the service. The Army of Virginia and that of the Potomac being united, the command was handed to the "Little Napoleon" of Peninsula fame, George B. McClellan. The South was overjoyed with its victory at Bull Run--twice it had unfurled its banner in triumph on this battlefield--twice its army had stood on the road that leads to Washington, only by some strange destiny of war to fail to enter it on the wave of victory. This subject, "The Battle of Antietam," is considered one of the turning points of the war, for it was after this battle that President Lincoln issued his emancipation proclamation, although it is said that he had it prepared for some time but on account of the continued defeat of his armies in Virginia he could not see his way clear to declare it until after the battle of Antietam. Lee's army, 50,000 strong, crossed the Potomac and concentrated around Frederick, Md., only about forty miles from Washington. When it became known that Lee was advancing into Maryland and was threatening Washington, McClellan pushed his forces forward to encounter the invaders. The people of the vicinity, and even at Harrisburg, Baltimore and Philadelphia, were filled with consternation. Their fear was intensified by the memory of Second Bull Run, a few weeks before, and by the fact that at this time General Bragg was marching northward across Kentucky with a great army, threatening Louisville and Cincinnati.