The Confederates were equally alert, and opened a heavy fire upon the retreating columns. The Union force under McCall, by being skillfully handled, succeeded in reaching their new position on the Chickahominy heights, and on the morning of the new day made ready for action. The selection of this ground had been well made; they occupied a series of heights fronted on the west by a cycle shaped stream. The land beyond was an open country, through which a creek meandered sluggishly, and beyond this a densely tangled undergrowth. Around the Union position also were many patches of woods, affording cover for the reserves. To protect the Federals, trees had been felled along their front, out of which barriers, protected by rails and knapsacks, were erected. Jackson's forces had united with those of Longstreet and the two Hills, and were advancing with grim determination of victory. It was two o'clock, on June 28th, when General A. P. Hill swung his division into line for the attack. He was unsupported by the other divisions, which had not yet arrived on the field. His columns moved rapidly toward the Union front, and was met by a hailstorm of lead from Porter's artillery, which sent messages of death to the approaching lines of gray. The Confederate front recoiled from the incessant outpour of grape, canister and shell. The repulse threw the Confederates into great confusion. Many left the field in disorder. Others threw themselves on the ground to escape the withering fire, while some held their places. The Federals were reënforced by General Slocum's division of Franklin's corps. Lee ordered a general attack upon the entire Union front. Reënforcements were brought up to take the place of the shattered regiments. The troops moved forward in the face of a heavy fire and pressed up the hillside against the Union line at fearful sacrifice. It was a death grapple for the mastery of the field.