Naturally Lee strengthened his force near where Ewell had secured a lodgment within the breastworks of Culp's Hill, with the purpose of making his main attack there; but Meade could not fail to see the utmost importance of driving out the enemy from his position. He shelled it at daylight on the 3d, and sent a strong body of infantry against the intruders. The Confederates made a desperate resistance, but in the end were expelled, and the Union line re-established. It will be seen that this miscalculation of Lee compelled him to change his plans. Sitting on his horse, riding back and forth, often halting and scanning the battlefield through his glasses, and continually consulting his officers, he finally decided to direct his supreme effort against the Union centre. Success there meant the defeat and rout of the Union army, for, if the two wings could be wedged apart, they would be overwhelmed and destroyed by the charging Confederates. But the impressive fact was as well known to the Federals as to their enemies, and nothing was neglected that could add to the strength of their position. All night long troops kept arriving, and in the moonlight were assigned to their positions for the morrow. It took Lee several hours to complete his preparations for the assault upon the Union centre. At noon he had 145 cannon posted on Seminary Ridge, opposite Meade's centre, while Meade had 80 pieces of artillery lined along the crest of Cemetery Hill. PICKETT'S CHARGE. At noon the Confederates opened with all their cannon, their object being to silence the batteries in front, to clear the way for the charge against the Union centre. The eighty Federal pieces replied, and for two hours the earth rocked under the most prodigious cannonade ever heard on this side of the Atlantic. Then the Union fire gradually ceased, and, as the vast volume of smoke slowly lifted, a column of 5,000 gray-coated men were seen to issue from the Confederate lines more than a mile away and advance at a steady stride toward the Union intrenchments. Their bayonets shone in the afternoon sun, and their fluttering battle-flags, the splendid precision of their step, and their superb soldierly appearance made so thrilling a picture that an involuntary murmur of admiration ran along the Union lines, even though these same men were advancing to kill and wound them. They formed the division of General George E. Pickett, and no more magnificent charge was ever made. They advanced in a double line, their own artillery ceasing firing as they gradually passed within range with beautiful regular step, which seemed to hasten, as if even with their perfect discipline they could not restrain, their eagerness to join in the death-grapple.