July 1st found the retreating host concentrated on Malvern Hill, a plateau a mile and a half long and half as broad, with ravines toward the advancing enemy. Here McClellan planted seventy cannon, rising tier upon tier up the slope, seven heavy siege guns crowning the crest. The position was impregnable, but Lee determined to attack. Shortly before sunset his men advanced boldly to the charge, but were mowed down by the terrible concentrated fire of the batteries. The hill swarmed with infantry as well, sheltered by fences and ravines, while shells from the gunboats in James River could reach every part of the Confederate line. Yet not till nine in the evening did Lee let the useless carnage cease. Badly demoralized as the opposing army was, McClellan at midnight withdrew to Harrison's Landing, farther down the James. [Illustration: Battle.] General J. E. B. Stuart's Raid upon Pope's Headquarters, August 22, 1862, when Pope's despatch book fell into the hands of the Confederates. During the Seven Days' Retreat he had lost 15,000 men; the Confederates somewhat more. Military authorities unite in pronouncing McClellan's change of base "brilliantly executed;" but the campaign as a whole was a failure, discouraging the country as much as Bull Run had done. McClellan prepared and fully expected to move on Richmond again from this new base, but early in August received orders to withdraw from the Peninsula. By the middle of the month the dejected Army of the Potomac was on its way north. The last of June the Union forces in West Virginia, the Shenandoah Valley, and in front of Washington were consolidated into one army, and the same General Pope who had recently won laurels by the conquest of Island Number Ten, put in command. His headquarters, he announced, were to be in the saddle, and those who had criticised McClellan gave out that the Union army's days of retreating were past. McClellan was called from the Peninsula to strengthen this new movement.