[73] "I instructed the chiefs of artillery and battery commanders to withhold their fire for fifteen or twenty minutes after the cannonade commenced, then to concentrate their fire with all possible accuracy upon those batteries which were most destructive to us, but slowly, so that when the enemy's ammunition was exhausted we should have enough left to meet the assault."--_Gen. Hunt, Chief of Artillery._ [74] Pickett's division with two brigades absent was probably five thousand five hundred strong, Heth's not less, and the three supporting brigades as many more. The troops were no doubt selected as the very best that offered. X THE RETREAT [Sidenote: Gettysburg evacuated.] [Sidenote: Lee's New Position.] Thrice had the sun gone down on that ensanguined field, where one hundred and fifty thousand men had striven for the mastery and forty thousand sealed their devotion with their blood. Exhausted by their efforts, the Confederates thought only of making good their retreat. Gettysburg was immediately evacuated and both wings drawn back on the main body, so that, as now re-formed and contracted, Lee's army stretched from Oak Hill to the peach orchard. Behind this line, and under cover of its woods, he was now getting ready to retreat. Such plain indications could hardly be overlooked.[75] A reconnoisance from the Union left found the Confederates retiring. During the night the Union troops went forward to the battlefield of the 2d. [Sidenote: Lost Chances.] Lee's lost opportunity on the 1st was as nothing to Meade's on the 3d. It came when the Confederates were in the confusion resulting from their repulse. It was lost, however, because the great captain was not there. Meade was unequal to exacting a supreme effort at this moment, either from his army or himself. To let slip this opportunity was to tempt fortune itself, and it never came again. [Sidenote: Strange Inaction.] But if from any of the many causes alleged,[76] or all of them put together, the one chance out of a thousand, for which all this marching and fighting had been going on, had eluded Meade's grasp, or if it be conceded that he found Lee's new position so strong as to hold out no hope of a successful assault, history will still demand to know why this beaten army, short of ammunition, encumbered with its wounded, its prisoners, and its wagons, thirty to forty miles from the Potomac, with a mountain defile to pass and a wide river to cross, was suffered to march off unmolested with all its immense spoil, and not only to do that, but to remain eleven days between Gettysburg and the Potomac without being once seriously attacked. [Sidenote: Lee in a Tight Place.]