for approximately ten miles, but there were several points where there were no fortifications built yet, and Cold Harbor was one of them. On June 1 and 2 both Grant and Lee were still waiting for reinforcements to arrive. Hancock's men had marched all night and arrived too exhausted for an immediate attack that morning. Grant agreed to let the men rest and postponed the attack until 5 p.m., and then again until 4:30 a.m. on June 3. However, Grant and Meade did not give specific orders for the attack, leaving it up to the corps commanders to decide where they would coordinate and attack the Confederate lines, as no senior commander had yet reconnoitered the latest Confederate developments. Grant had not yet learned that overnight Lee had hastily constructed entrenchments to thwart any breach attempt at Cold Harbor. Grant had put off making an attack twice and was anxious to make his move before the rest of Lee's army arrived. On the morning of June 3, the third day of the thirteen-day battle, with a force of more than 100,000 men, against Lee's 59,000, Grant attacked not realizing that Lee's army was now well entrenched, much of it obscured by trees and bushes. Grant's army suffered 12,000–14,000 casualties, while Lee's army suffered 3,000–5,000 casualties, but Lee was less able to replace them. The unprecedented number of casualties was shocking by all accounts and heightened anti-war sentiment in the North. After the battle Grant wanted to appeal to Lee under the white flag for each side to gather up their wounded, most of them Union soldiers, but Lee insisted that a total truce be enacted and while they were deliberating all but a few of the wounded died in the field. Without giving an apology for the disastrous defeat in his official military report, Grant confided in his staff after the battle and years later wrote in his memoirs that he "regretted that the last assault at Cold Harbor was ever made. I might say the same thing of the assault ... at Vicksburg." Siege of Petersburg (1864–1865) Undetected by Lee, Grant moved his army south of the James River, freed Butler from the Bermuda Hundred, and advanced toward Petersburg, Virginia's central railroad hub. Beauregard defended Petersburg, and Lee's veteran reinforcements arrived on June 18, resulting in a nine-month siege. Northern resentment grew. Sheridan was assigned command of the Union