He was a trifle too late, however, and a stubborn defense was made there on the fourteenth, giving Lee time to bring up the remainder of his forces for the decisive battle at Sharpsburg or Antietam, as the action is variously called at the South and at the North. McClellan finally carried the gaps at cost of a loss of 2,000 men--the Confederates losing a like number. But in the meanwhile McClellan had lost all the strategic advantage that he was striving for. It had been his hope to push his columns through the gaps--as he might have done twenty-four hours earlier without serious resistance--and to occupy commanding positions between Lee's widely scattered forces, from which, with his vastly superior numbers he might conquer them in detail, probably compelling Lee's surrender as a part of the price exacted. But McClellan was twenty-four hours late. He therefore had to fight all day in order to force his way through passes that a day earlier had been practically open to him. These actions were fought on the fourteenth of September, 1862. They were quite separate in their strategy and action, but they are classed together in history as the Battle of South Mountain. The struggle at both points was a fierce one and the casualties were heavy on either side. At the end of it all McClellan held the passes and was free to push his army through them. To that extent he had won a victory. But by his stout defense Lee had gained the time he so badly needed in which to bring his scattered forces together for the decisive struggle, and as that was his sole object at the time, he justly felt that he had accomplished the purpose with which he had undertaken the battle. Lee promptly prepared himself for the decisive struggle. Retiring behind Antietam Creek, he took up a strong position and awaited McClellan's assault. He had by this time an army of less than 38,000 men with which to meet McClellan's 70,000 or 75,000--for reinforcements were hourly coming to the Federal commander, and none to the Confederate.