McClellan had gradually felt his way down to the vicinity of Richmond, when the rebels, out of patience with him, fell upon his forces, and drove him to the shelter of the gunboats on the James, after his glorious army had fought some of the most brilliant defensive battles of the war. The country cried out against him for this delay, derided his use of the pick and shovel, and unhorsed him because he neglected his opportunities. While he was still resting from his hard-fought but useless battles, the government removed him from his position of general-in-chief, and assigned General Halleck to his place, probably on account of his brilliant operations before Corinth, where he had played through the farce of "regular approaches," though with none of the tragic features which attended it before Richmond. Halleck was now in power, and one of his first acts, even before he left for Washington, was to offer the command of the army of the Tennessee to Colonel Allen, a quartermaster. This gentleman, who was to be promoted to the required rank, to enable him to accept the command, had the good sense to decline it, and Grant was permitted to retain his position. He was deprived of nearly his entire force, and left to maintain a defensive position. He made his headquarters at Corinth, protecting the railroad communications, and holding what had before been gained. He spent the summer in this manner, though with enough to do to keep him busy, for he was continually harassed and threatened by the enemy under Van Dorn and Price. Halleck, in his new capacity of general-in-chief, had his hands full in attending to McClellan and Pope. Grant seems to have been forgotten, and was thereby permitted to manage the affairs of his district without being hampered with instructions. The North was in danger of invasion in Maryland, rendered possible by the disastrous battles of Pope, and in Ohio by the rebel army under General Bragg, who had out-generaled the prudent and deliberate Buell. In these emergencies, Grant's men were taken from him, till the smallness of his force afforded even him no little anxiety. Van Dorn, in command of the rebels in this section, ordered Price to seize Iuka, which was done. Van Dorn himself was four days' march to the south-west, threatening Corinth. Grant wished to overwhelm Price at Iuka, without exposing Corinth to capture by Van Dorn. He sent out two columns, one under Rosecrans and the other under Ord, to accomplish this purpose. A sharp battle followed, but the intention to capture Price's army failed, on account of a delay of one of the columns in reaching the point of attack. The rebels escaped, and effected a junction with Van Dorn.